Chemistry
Chemistry is the
science
of
matter. The branch of the natural sciences dealing with the
composition of
substances and their
properties and
reactions.
Biology
-
Elements -
Bonds -
Carbon -
Thermodynamics
Glossary of Chemistry Terms (wiki)
-
Types of Chemistry
Chemistry Tools -
Science Equipment -
Scopes -
Microscopes
Khan Chemistry
(videos) -
ACS Reactions (youtube)
Chemistry Stack Exchange
is a question and answer site for scientists.
Middle
School Chemistry -
Do it Yourself Chemistry
(DIY)
Chemist is a
scientist trained in the study of chemistry.
Chemists study the composition of
matter and its properties. Chemists
carefully describe the properties they study in terms of quantities,
with detail on the level of
molecules and their component
atoms.
Chemists carefully
measure substance proportions,
reaction rates, and
other chemical properties.
Drug
Research.
Chemical is a
substance produced by
reactions or used in reactions involving atomic or
molecular changes. A
compound
or a substance that has been purified or prepared, especially
artificially.
Material produced
by or used in a reaction involving changes in
atoms or molecules. Relating to or used
in chemistry.
Chemical Substance is a form of
matter that has constant chemical
composition and characteristic properties. It cannot be separated into
components by
physical separation methods, i.e., without breaking
chemical bonds. Chemical
substances can be chemical elements, chemical
compounds, ions or alloys.
Carbon.
Substrate is the substance that is acted upon by an
enzyme or
ferment. A
surface on which an
organism grows or is attached. Any stratum or
layer lying underneath another.
Antigen in
immunology is any substance as a
toxin or
enzyme that stimulates an
immune response in the body, especially the production of antibodies.
Mole
is the unit of
measurement for
amount of substance in the International System of Units (
SI).
The unit is defined as the amount or sample of a chemical substance that
contains as many constitutive particles, e.g., atoms, molecules, ions,
electrons, or photons, as there are atoms in 12 grams of
carbon-12 (12C),
the isotope of carbon with
standard atomic weight 12 by definition. This number is expressed by
the
Avogadro constant, which has a value of approximately
6.022140857×1023 mol−1. The mole is an
SI
base unit, with the unit symbol mol.
Chemical Property is any of a
material's properties that becomes
evident during, or after, a
chemical reaction; that is, any quality that
can be established only by changing a substance's chemical identity.
Simply speaking, chemical properties cannot be determined just by
viewing or touching the substance; the substance's internal
structure
must be affected greatly for its chemical properties to be investigated.
When a
substance goes under a chemical reaction, the properties will
change drastically, resulting in chemical change. However, a catalytic
property would also be a chemical property.
Temperature.
Chemical
Composition is the identity, and relative number, of the
elements
that make up any particular
compound. It refers to the
arrangement, type, and ratio of atoms in
molecules of chemical
substances. Chemical composition varies when chemicals are added or
subtracted from a substance, when the ratio of substances changes, or
when other chemical changes occur in chemicals. The chemical composition
of a pure substance corresponds to the relative amounts of the elements
that constitute the substance itself. It can be expressed by the
empirical
formula. For example the formula for
water is H2O: this means
that each molecule is constituted by 2 atoms of hydrogen (H) and 1 atom
of oxygen (O). The chemical composition of a mixture can be defined as
the distribution of the single substances that constitute the mixture,
called "
components". In other words, it is defined giving the
concentration of each component. Because there are different ways to
define the concentration of a component, as a consequence there are also
different ways to define the composition of a mixture. For example it can
be expressed as molar fraction, volume fraction, mass fraction, molality,
molarity or normality. Chemical composition of a mixture can be
represented
graphically in plots like ternary plot and quaternary plot.
Mixture
is a material
system made up of two or more different substances which
are mixed but are not
combined chemically. A mixture refers to the
physical combination of two or more substances in which the identities
are retained and are mixed in the form of
solutions, suspensions, and
colloids.
Extraction -
Combining Different Foods.
Blend is to add together different
elements. To mix a substance with another
substance so that they
combine together.
Combine is to
add
together from different sources in order to
form a whole. To
mix. To add together different elements.
Volume is the amount of
3-dimensional space
occupied by an object. A
relative amount.
Concentration is the
strength of a solution or the
number of molecules of a substance in a
given volume. The
spatial property of being crowded together. Increase in density or
the amount per unit
size.
Homogeneous is consisting of parts
that are
alike or
all of the
same kind.
Something that is
uniform
in nature or character throughout. In the context of chemistry,
homogenous is used to describe a mixture that is uniform in
structure or
composition.
Homogeneous material or system has the
same properties at every point;
it is uniform without irregularities. A uniform electric field would be
compatible with homogeneity.
Uniform
is being the same throughout in
structure or
composition. Always the same or showing a single form or character in all
occurrences. Not differentiated. Evenly spaced.
Chemical Formula is a way of
presenting information about the chemical proportions of
atoms that constitute a particular
chemical
compound or
molecule,
using chemical
element symbols, numbers, and
sometimes also other
symbols,
such as parentheses, dashes, brackets, commas and plus (+) and minus (−)
signs. These are limited to a single typographic line of
symbols, which may include subscripts
and superscripts. A chemical formula is not a chemical name, and it
contains no words. Although a chemical formula may imply certain simple
chemical structures, it is not the same as a full chemical structural
formula. Chemical formulae can fully specify the structure of only the
simplest of molecules and chemical substances, and are generally more
limited in power than chemical names and structural formulae. The
simplest types of chemical formulae are called empirical formulas, which
use letters and numbers indicating the numerical proportions of atoms of
each type. Molecular formulae indicate the simple numbers of each type of
atom in a molecule, with no information on structure. For example, the
empirical formula for glucose is CH2O (twice as many hydrogen atoms as
carbon and oxygen), while its molecular formula is C6H12O6 (12 hydrogen
atoms, six carbon and oxygen atoms). Sometimes a chemical formula is
complicated by being written as a condensed formula (or condensed
molecular formula, occasionally called a "semi-structural formula"),
which conveys additional information about the particular ways in which
the atoms are chemically bonded together, either in covalent bonds, ionic
bonds, or various combinations of these types. This is possible if the
relevant
bonding is easy to show in one dimension. An
example is the condensed molecular/chemical formula for ethanol, which is
CH3-CH2-OH or CH3CH2OH. However, even a condensed chemical formula is
necessarily limited in its ability to show complex bonding relationships
between atoms, especially atoms that have bonds to four or more different
substituents. Since a chemical formula must be expressed as a single line
of chemical element symbols, it often cannot be as informative as a true
structural formula, which is a graphical representation of the spatial
relationship between atoms in chemical compounds (see for example the
figure for butane structural and chemical formulae, at right). For
reasons of structural complexity, a single condensed chemical formula (or
semi-structural formula) may correspond to different molecules, known as
isomers. For example glucose shares its molecular formula C6H12O6 with a
number of other sugars, including fructose, galactose and mannose. Linear
equivalent chemical names exist that can and do specify uniquely any
complex structural formula (see chemical nomenclature), but such names
must use many terms (words), rather than the simple element symbols,
numbers, and simple typographical symbols that define a chemical formula.
Chemical formulae may be used in chemical equations to describe chemical
reactions and other chemical transformations, such as the dissolving of
ionic compounds into solution. While, as noted, chemical formulae do not
have the full power of structural formulae to show chemical relationships
between atoms, they are sufficient to keep track of numbers of atoms and
numbers of electrical charges in chemical reactions, thus balancing
chemical equations so that these equations can be used in chemical
problems involving conservation of atoms, and conservation of electric
charge.
Math Formula -
Science Formula
Powder engineering adds AI to the mix. Revolutionary technology that
is 350 times faster than conventional methods. A research team has
developed a new simulation method that accurately predicts powder mixing
using AI, and has succeeded in increasing calculation speed by
approximately 350 times while maintaining the same level of accuracy as
conventional methods. This method is expected to not only pave the way
for more efficient and precise powder mixing processes but also open up
new possibilities for industries seeking to enhance product quality and
streamline production.
Reactions
Reaction is a
process in which one or more
substances are
changed into others. A bodily process occurring due to the
effect of some antecedent
stimulus or agent. Reaction in mechanics is the
equal and opposite
force
that is produced when any
force is applied to a body. Reaction can also
mean an idea evoked by some
experience. A
response that reveals a
person's feelings or attitude.
Chemical Reaction is a
process that leads to the
transformation of one set of
chemical substances to another. Classically, chemical reactions
encompass changes that only involve the positions of
electrons in the
forming and breaking of
chemical bonds between atoms, with no change to
the nuclei (no change to the elements present), and can often be
described by a chemical equation.
Oxidation -
Fire -
Electrochemical
Reaction -
Catalysis -
Thermal Reactions -
Explosions
-
Combustion -
Stimulus -
Cause and Effect
-
Side-Effect
Chemical Energy is the
potential of a
chemical substance to undergo a
transformation through a chemical
reaction to transform other chemical substances. Examples include
batteries, gasoline,
food and more. Breaking or making of chemical
bonds involves
energy, which may be either
absorbed or evolved from a chemical system.
Activation Energy is the minimum amount of energy that must be
available to reactants for a chemical reaction to occur.
Binding Energy
- Fusion -
Nucleosynthesis.
Criticality Accident is an uncontrolled nuclear fission
chain reaction. It is
sometimes referred to as a critical excursion, a critical power
excursion, or a divergent chain reaction.
Interaction is a
kind of
action that occurs
as
two or more objects have an
effect upon one
another.
Interface.
Bond -
Force of Attraction -
Coexist -
Fundamental Interaction
A single-molecule guide to understanding chemical reactions better.
Scientists from Tokyo Institute of Technology decided to explore DNA
"hybridization" (formation of a double-stranded DNA from two
single-stranded DNA) by measuring the changes in single-molecule
electrical conductivity using an
scanning
tunneling microscope. Single-molecule investigations can often reveal
new details on chemical and biological processes that cannot be
identified in a bulk collection of molecules due to the averaging out of
individual molecule behavior.
Computational model captures the elusive transition states of chemical
reactions. Researchers developed a way to quickly calculate the
transition state structure of a chemical reaction, using machine-learning
models. The structures of these transition states can be calculated using
techniques based on
quantum chemistry.
Inert is used to describe a substance that is
not chemically reactive. From a
thermodynamic perspective, a substance is inert, or nonlabile, if it is
thermodynamically unstable (positive standard Gibbs free energy of
formation) yet
decomposes at a slow, or negligible
rate.
Inert Gas
is a gas that
does not undergo chemical reactions
under a set of given conditions. The noble gases often do not
react with many substances and were historically referred to as the inert
gases. Inert gases are used generally to avoid unwanted chemical
reactions
degrading a sample. These undesirable
chemical reactions are often
oxidation
and hydrolysis reactions with the oxygen and moisture in air. The term
inert gas is context-dependent because several of the noble gases can be
made to react under certain conditions. Purified argon and nitrogen gases
are most commonly used as inert gases due to their high natural abundance
(78.3% N2, 1% Ar in air) and low relative cost. Unlike noble gases, an
inert gas is not necessarily elemental and is often a compound gas. Like
the noble gases, the tendency for non-reactivity is due to the valence,
the outermost electron shell, being complete in all the inert gases. This
is a tendency, not a rule, as noble gases and other "inert" gases can
react to form compounds.
Inert is
something chemically inactive and having only a limited ability to react
chemically. Slow and apathetic or unable to move or resist motion.
High Reaction Rates even without Precious Metals. Non-precious metal
nanoparticles could one day replace expensive catalysts for hydrogen
production. However, it is often difficult to determine what reaction
rates they can achieve, especially when it comes to oxide particles. This
is because the particles must be attached to the electrode using a binder
and conductive additives, which distort the results. With the aid of
electrochemical analyses of individual particles, researchers have now
succeeded in determining the activity and substance conversion of
nanocatalysts made from cobalt iron oxide -- without any binders.
Catalysis in chemistry is a substance that initiates or
accelerates a
chemical reaction without itself being affected. It is the process
of
increasing the rate of a chemical reaction by adding a substance known
as a catalyst, which is not consumed in the
catalyzed reaction and can
continue to act repeatedly. Because of this, only very small amounts of
catalyst are required to alter the reaction rate in principle. Catalysis
can also mean something that
causes an important
event to happen.
New atomic-scale understanding of catalysis could unlock massive energy
savings. In an advance they consider a breakthrough in
computational chemistry research,
chemical engineers have developed a model of how catalytic reactions
work at the
atomic scale. This
understanding could allow engineers and chemists to develop more
efficient catalysts and tune industrial processes -- potentially with
enormous energy savings, given that 90% of the products we encounter in
our lives are produced, at least partially, via catalysis. Catalyst
materials accelerate chemical reactions without undergoing changes
themselves.
Cofactor in biochemistry is a non-protein chemical compound or
metallic ion that is required for an enzyme's activity as a catalyst, a
substance that increases the rate of a chemical reaction. Cofactors can
be considered "helper molecules" that assist in biochemical
transformations. The rates at which these happen are characterized by in
an area of study called enzyme kinetics.
Magic Number refers to a specific properties (such as stability) for
only certain representatives among a distribution of species.
Bacterial Enzyme Enables Reactions -
Drug Research
Unimolecular Reactions is where one reactant undergoes
bond breaking
and/or
bond forming to yield different products.
Bimolecular Reactions is where two reactants collide and then
undergo bond breaking and/or forming to yield different products.
Termolecular Association Reactions is where
two reactants collide to form a molecular complex with a new chemical
bond between the two reactants and a third
molecule, known as the bath
gas, removes some of the internal
kinetic
energy of that molecule to stabilize it. New class of chemical
reactions involving three molecules that each participate in the breaking
and forming of
chemical bonds. The reaction of three different molecules
is enabled by an "ephemeral collision complex," formed from the collision
of two molecules, which lives long enough to collide with a third
molecule.
Cause and
Effect.
Single Molecule Control for a Millionth of a Billionth of a Second.
Mechanical Force as a new way of starting Chemical Reactions.
Researchers have shown mechanical force can start chemical reactions,
making them cheaper, more broadly applicable, and more environmentally
friendly than conventional methods.
Researchers monitor electron behavior during chemical reactions for the
first using laser pulses and supercomputing simulations, researchers
observe
electrons' motions in real
time.
Chemical Ecology
examines the role of
chemical interactions between
living organisms and their
environment, as
the consequences of those interactions on the ethology and evolution of
the organisms involved. It is thus a vast and highly interdisciplinary
field. Chemical ecology studies focuses on the
biochemistry of ecology and the specific molecules or groups of
molecules termed semiochemicals that function as signals to initiate,
modulate, or terminate a variety of biological processes such as
metabolism. Molecules that serve in such roles typically are readily
diffusible organic substances of low molecular mass that derive from
secondary metabolic pathways, but also include peptides and other natural
products. Chemical ecological processes mediated by
semiochemicals include ones that are intraspecific (occurring within
a species) or that are interspecific (occurring between species). A
variety of functional subtypes of
signals are known, including
pheromones, allomones, kairomones, and attractants and repellents. It can
sometimes be hard to differentiate from other biological fields and may
require many disciplines working together in a study.
Briggs-Rauscher Reaction is one of a small number of known
oscillating chemical reactions. It is
especially well suited for demonstration purposes because of its visually
striking colour changes: the freshly prepared colourless solution slowly
turns an amber colour, suddenly changing to a very dark blue. This slowly
fades to colourless and the process repeats, about ten times in the most
popular formulation, before ending as a dark blue liquid smelling
strongly of iodine.
Mysterious organic scum boosts chemical reaction efficiency, may reduce
chemical waste. Chemical manufacturers frequently use toxic solvents
such as alcohols and benzene to make products like pharmaceuticals and
plastics. Researchers are examining a previously overlooked and
misunderstood phenomenon in the chemical reactions used to make these
products. This discovery brings a new fundamental understanding of
catalytic chemistry and a steppingstone to practical applications that
could someday make chemical manufacturing less wasteful and more
environmentally sound.
Functional Group
are specific groups (
moieties)
of atoms or
bonds within molecules that are responsible for the
characteristic
chemical reactions of those molecules. The same functional
group will undergo the same or similar chemical reaction(s) regardless of
the size of the molecule it is a part of. This allows for systematic
prediction of chemical reactions and behavior of chemical compounds and
design of
chemical syntheses. Furthermore, the reactivity of a functional
group can be modified by other functional groups nearby. In organic
synthesis, functional group interconversion is one of the basic types of
transformations.
Identifying right-handed and left-handed molecules is a crucial step
for many applications in chemistry and pharmaceutics. Chemists have now
presented an original and very sensitive method. The researchers use
laser pulses of extremely short duration to excite electrons in molecules
into twisting motion, the direction of which reveals the molecules’
handedness.
Chirality is a geometric property of some molecules and ions. A
chiral molecule/ion is non-superimposable on its mirror image. The
presence of an asymmetric carbon center is one of several structural
features that induce chirality in organic and inorganic molecules.
Absolute Configuration refers to the spatial arrangement of the atoms
of a chiral molecular entity (or group) and its stereochemical
description e.g. R or S, referring to Rectus, or Sinister, respectively.
Chemical Polarity is a separation of
electric charge leading to a
molecule or its
chemical groups having an
electric
dipole or multipole moment. Polar molecules must contain polar bonds
due to a difference in electronegativity between the bonded atoms. A
polar molecule with two or more polar bonds must have a geometry which is
asymmetric in at least one direction, so that the bond dipoles do not
cancel each other.
Polar molecules interact through dipole–dipole
intermolecular forces and hydrogen bonds. Polarity underlies a number of
physical properties including surface tension, solubility, and melting
and boiling points.
Water (H2O) is an example of
a polar molecule since it has a slight positive charge on one side and a
slight negative charge on the other.
Synthesis -
Enzymes -
Amino Acid
Molecules change their behaviors under a polariton leader. Chemists
sought to answer was whether polariton modes and dark modes (the
molecular byproduct of
polariton creation) both modify chemical reactions. The article shows
unambiguously that chemical reactions only occur with
polaritons. In recent years, manipulating chemistry using hybrid
light-matter states called polaritons has generated much research as it
combines the speed and efficiency of light with the reactivity and strong
interactions of matter. Vibrational polaritons are formed when a specific
vibrational motion of the molecule and photon creates a "spring" that
allows them to quickly exchange energy. This is called vibrational strong
coupling.
Chemical Similarity refers to the
similarity of chemical
elements, molecules or chemical compounds with respect to either
structural or functional qualities, i.e. the effect that the chemical
compound has on
reaction partners in inorganic or biological settings.
Biological effects and thus also similarity of effects are usually
quantified using the biological activity of a compound. In general
terms, function can be related to the chemical activity of compounds (among others).
Chemistry Types
Organic Chemistry is a chemistry subdiscipline involving the
scientific study of the
structure, properties, and
reactions of organic
compounds and organic
materials, i.e., matter in its various forms that
contain carbon atoms. Study of structure includes many physical and
chemical methods to determine the chemical composition and the chemical
constitution of organic compounds and materials. Study of properties
includes both physical properties and chemical properties, and uses
similar methods as well as methods to evaluate chemical reactivity, with
the aim to understand the behavior of the organic matter in its pure
form (when possible), but also in solutions, mixtures, and fabricated
forms. The study of organic reactions includes probing their scope
through use in preparation of target compounds (e.g., natural products,
drugs, polymers, etc.) by chemical synthesis, as well as the focused
study of the reactivities of individual organic molecules, both in the
laboratory and via theoretical (in silico) study.
Organic Materials Database -
A crash course in Organic Chemistry: Jakob Magolan (youtube).
Chemical Engineering -
Green
Chemistry -
Medicinal
Chemistry
Inorganic Chemistry
deals with the
synthesis and behavior of inorganic and organometallic
compounds. This field covers all chemical compounds except the myriad
organic compounds (carbon based compounds, usually containing C-H
bonds), which are the subjects of organic chemistry. The distinction
between the two disciplines is far from absolute, as there is much
overlap in the subdiscipline of organometallic chemistry. It has
applications in every aspect of the chemical industry, including
catalysis, materials science, pigments, surfactants, coatings,
medications, fuels, and agriculture. A key goal in synthetic organic
chemistry is the design of reagents to achieve chemical transformations
at specific sites in a molecule without
protection and
deprotection steps.
Synthetic Chemistry
-
Synthetic
Biology
Nuclear
Chemistry is a sub-discipline
of chemistry that involves the chemical reactions of unstable and
radioactive elements where both electronic and
nuclear changes may
occur.
Physical
Chemistry is the study of macroscopic,
atomic, subatomic, and particulate phenomena in chemical systems in
terms of the principles, practices and concepts of physics such as
motion, energy, force,
time,
thermodynamics, quantum chemistry,
statistical mechanics, analytical dynamics and chemical equilibrium.
Quantum Chemistry or molecular quantum mechanics is a branch of
physical chemistry focused on the application of quantum mechanics to
chemical systems, particularly towards the quantum-mechanical calculation
of electronic contributions to physical and chemical properties of
molecules, materials, and solutions at the atomic level.
Photo-Electro-Chemistry is a subfield of study within physical
chemistry concerned with the interaction of
Light with electrochemical
systems. It is an active domain of investigation. One of the pioneers of
this field of
electrochemistry was the German electrochemist Heinz Gerischer. The
interest in this domain is high in the context of development of
renewable energy conversion and
storage technology.
Photo-Chemistry is the branch of chemistry concerned with the
chemical
effects of light.
Generally, this term is used to describe a chemical reaction caused by
absorption of ultraviolet (wavelength from 100 to 400 nm), visible light
(400 – 750 nm) or infrared radiation (750 – 2500 nm). In nature,
photochemistry is of immense importance as it is the basis of
photosynthesis,
vision, and the formation of vitamin D with
sunlight. Photochemical reactions proceed differently than
temperature-driven reactions. Photochemical paths access high energy
intermediates that cannot be generated thermally, thereby overcoming
large activation barriers in a short period of time, and allowing
reactions otherwise inaccessible by thermal processes. Photochemistry is
also destructive, as illustrated by the photodegradation of plastics.
Photonics -
Fuel Cells -
Electrochemistry
(Batteries)
Stereo-Chemistry is a subdiscipline of chemistry, involves the study
of the relative spatial arrangement of atoms that form the structure of
molecules and their manipulation. The study of stereochemistry focuses on
stereoisomers, which by definition have the same molecular formula and
sequence of bonded atoms (constitution), but differ in the
three-dimensional orientations of their atoms in space. For this reason,
it is also known as 3D chemistry—the prefix "stereo-" means
"three-dimensionality".
Biochemistry
sometimes called
biological chemistry, is the study of chemical
processes within and relating to living
organisms. By controlling
information flow through biochemical signaling and the flow of chemical
energy through metabolism, biochemical processes give rise to the
complexity of life. Over the last decades of the 20th century,
biochemistry has become so successful at explaining living processes
that now almost all areas of the life sciences from botany to medicine
to genetics are engaged in biochemical research. Today, the main focus
of pure biochemistry is on understanding how biological molecules give
rise to the processes that occur within living cells, which in turn
relates greatly to the study and understanding of tissues, organs, and
whole organisms-that is, all of biology.
Biochemist are
scientists that are trained in biochemistry.
Bioreactor -
Bioenergy
Polymer Chemistry is a chemistry subdiscipline that deals with the
structures, chemical
synthesis and properties of
polymers, primarily
synthetic
polymers such as
plastics and elastomers.
Polymer chemistry is
related to the broader field of
polymer science, which also encompasses
polymer physics and
polymer engineering.
Molding.
Shape-Memory Polymer are
polymeric smart
materials that have the ability to return from a deformed state
(temporary shape) to their original (permanent) shape induced by an
external stimulus (trigger), such as temperature change. Shape-memory
materials "remember" their original shape and return to it after they are
deformed. They are commonly metallic alloys that make possible
"unbreakable" eyeglass frames and quieter jet engines.
Natural
Rubber consists of polymers of the organic compound
isoprene,
with minor impurities of other organic compounds, plus water. Malaysia
and Indonesia are two of the leading rubber producers. Forms of
polyisoprene that are used as natural rubbers are classified as
elastomers. Currently, rubber is harvested mainly in the form of the
latex from the rubber tree or others. The latex is a sticky, milky
colloid drawn off by making incisions in the bark and collecting the
fluid in vessels in a process called "tapping". The
latex
then is refined into rubber ready for commercial processing. In major
areas, latex is allowed to coagulate in the collection cup. The
coagulated lumps are collected and processed into dry forms for
marketing. Natural rubber is used extensively in many applications and
products, either alone or in combination with other materials. In most of
its useful forms, it has a large stretch ratio and high resilience, and
is extremely waterproof.
Rubber -
Ames Laboratory, UConn discover superconductor with bounce.
Polymerization is a process of reacting
monomer molecules together in
a chemical reaction to form polymer chains or three-dimensional networks.
There are many forms of polymerization and different systems exist to
categorize them.
Polymers are high molecular mass
compounds formed by polymerization of
monomers,
which is a molecule that, as a unit, binds chemically or supramolecularly
to other molecules to form a supramolecular polymer.
Polyurethane is
a polymer composed of organic units joined by carbamate (urethane) links.
While most polyurethanes are thermosetting polymers that do not melt when
heated, thermoplastic polyurethanes are also available.
Polyester is a
category of polymers that contain the ester functional group in their
main chain. As a specific material, it most commonly refers to a type
called polyethylene terephthalate (PET). Polyesters include naturally
occurring chemicals, such as in the cutin of plant cuticles, as well as
synthetics such as polybutyrate. Natural polyesters and a few synthetic
ones are biodegradable, but most synthetic polyesters are not. The
material is used extensively in clothing.
Polyethylene is
the most common plastic, with around 80 million tonnes being produced
annually. Its primary use is in packaging (plastic bags, plastic films,
geomembranes, containers including bottles, etc.). Many kinds of
polyethylene are known, with most having the chemical formula (C2H4)n. PE
is usually a mixture of similar polymers of ethylene with various values
of n. Polyethylene is a thermoplastic however can become a thermoset
plastic when modified (such as cross-linked polyethylene).
Analytical Chemistry (Tools) -
Distillation
Geo-Chemistry is the science that uses the tools and
principles of chemistry to explain the mechanisms behind major
geological systems such as the Earth's crust and its oceans. The realm
of geochemistry extends beyond the Earth, encompassing the entire Solar
System and has made important contributions to the understanding of a
number of processes including mantle convection, the formation of
planets and the origins of granite and basalt.
Computational Chemistry is a branch of chemistry that uses
computer simulation to assist in solving chemical problems. It uses
methods of theoretical chemistry, incorporated into efficient computer
programs, to calculate the structures and properties of molecules and
solids. It is necessary because, apart from relatively recent results
concerning the hydrogen molecular ion (dihydrogen cation, see references
therein for more details), the quantum many-body problem cannot be
solved analytically, much less in closed form. While computational
results normally complement the information obtained by chemical
experiments, it can in some cases predict hitherto unobserved chemical
phenomena. It is widely used in the design of new drugs and materials.
Mechanochemistry is the coupling of mechanical and chemical phenomena
on a molecular scale and includes mechanical breakage, chemical behaviour
of
mechanically stressed solids
(e.g., stress-corrosion cracking or enhanced oxidation), tribology,
polymer degradation under shear, cavitation-related phenomena (e.g.,
sonochemistry and sonoluminescence), shock wave chemistry and physics,
and even the burgeoning field of molecular machines. Mechanochemistry can
be seen as an interface between chemistry and mechanical engineering. It
is possible to synthesize chemical products by using only mechanical
action. The mechanisms of mechanochemical transformations are often
complex and different from usual thermal or photochemical mechanisms. The
method of ball milling is a widely used process in which mechanical force
is used to achieve chemical processing and transformations. The special
issue of Chemical Society Review (vol. 42, 2013, Issue 18) is dedicated
to the theme of mechanochemistry. Fundamentals and applications ranging
from nano materials to technology have been reviewed. The mechanochemical
approach has been used to synthesize metallic nanoparticles, catalysts,
magnets, ?-graphyne, metal iodates, nickel–vanadium carbide and
molybdenum–vanadium carbide nanocomposite powders. Mechanochemistry is
radically different from the traditional way of dissolving, heating and
stirring chemicals in a solution. Because it eliminates the need for many
solvents, mechanochemistry could help make many chemical processes used
by industry more environmentally friendly.For example, the
mechanochemical process has been used as an environmentally preferable
way to synthesize pharmaceutically-attractive phenol hydrazones. The term
mechanochemistry is sometimes confused with
mechanosynthesis,
which refers specifically to the machine-controlled construction of
complex molecular products. Mechanochemical phenomena have been utilized
since time immemorial, for example in making fire. The oldest method of
making fire is to rub pieces of wood against each other, creating
friction and hence heat, allowing the wood to undergo combustion at a
high temperature. Another method involves the use of flint and steel,
during which a spark (a small particle of pyrophoric metal) spontaneously
combusts in air, starting fire instantaneously.
Theoretical Chemistry is the branch of chemistry which develops
theoretical generalizations that are part of the theoretical arsenal of
modern chemistry: for example, the concepts of chemical bonding, chemical
reaction, valence, the surface of potential energy, molecular orbitals,
orbital interactions, molecule activation, etc.
Analytical Chemistry studies and uses
instruments and
methods used to
separate, identify, and quantify matter. In practice, separation,
identification or quantification may constitute the entire analysis or be
combined with another method. Separation isolates analytes.
Qualitative Analysis identifies analytes and seeks to find the
elemental composition of inorganic compounds, while
Quantitative Analysis determines the numerical amount or
concentration and the determination of the absolute or relative
abundance. Analytical chemistry consists of classical,
wet
chemical methods and modern, instrumental methods. Classical
qualitative methods use separations such as
precipitation,
extraction,
and
distillation. Identification may be based on differences in color,
odor, melting point, boiling point, radioactivity or reactivity.
Classical quantitative analysis uses mass or volume changes to quantify
amount. Instrumental methods may be used to separate samples using
chromatography,
electrophoresis or
field flow fractionation,
which is a separation technique in which a field (thermal, electric,
magnetic, hydraulic, gravitational, ...) is applied to a diluted
suspension in a fluid or to a solution pumped through a long and narrow
channel, perpendicular to the direction of the field, in order to cause
the separation of particles present in the fluid, depending on their
differing "mobilities" under the force exerted by the field. Then
qualitative and quantitative analysis can be performed, often with the
same instrument and may use light interaction, heat interaction, electric
fields or magnetic fields. Often the same instrument can separate,
identify and quantify an analyte.
Analyte is a
substance or chemical constituent that is of interest in an analytical
procedure. Analytical chemistry is also focused on
improvements in
experimental design, chemometrics, and the creation of
new measurement tools. Analytical chemistry has broad applications to
medicine, science and engineering.
Lab Work.
Analytical is using
skilled
analysis such as
separating a whole into its
elemental parts or
basic principles. Analytical in
logic is of a proposition that is
necessarily true independent of
fact or
experience.
Process Analytical Chemistry is the application of analytical
chemistry with specialized techniques, algorithms, and sampling
equipment
for solving problems related to chemical processes. It is a specialized
form of analytical chemistry used for process manufacturing similar
to process analytical technology (PAT) used in the
pharmaceutical industry. The chemical
processes are for production and
quality
control of manufactured products, and process analytical technology
is used to determine the physical and chemical composition of the desired
products during a
manufacturing
process.
Analytical Balance is a class of balance designed to
measure small mass in the sub-milligram
range. The measuring pan of an analytical balance (0.1 mg or better) is
inside a transparent enclosure with doors so that dust does not collect
and so any air currents in the room do not affect the balance's
operation. This enclosure is often called a draft shield. The use of a
mechanically vented balance safety enclosure, which has uniquely designed
acrylic airfoils, allows a smooth turbulence-free airflow that prevents
balance fluctuation and the measure of mass down to 1 μg without
fluctuations or loss of product. Also, the sample must be at room
temperature to prevent natural convection from forming air currents
inside the enclosure from causing an error in reading. Single pan
mechanical substitution balance maintains consistent response throughout
the useful capacity is achieved by maintaining a constant load on the
balance beam, thus the fulcrum, by subtracting mass on the same side of
the beam to which the sample is added. Electronic analytical scales
measure the force needed to counter the mass being measured rather than
using actual masses. As such they must have calibration adjustments made
to compensate for gravitational differences. They use an electromagnet to
generate a force to counter the sample being measured and outputs the
result by measuring the force needed to achieve balance. Such measurement
device is called electromagnetic force restoration sensor.
Detection Limit or Limit of Detection is
the
lowest quantity of a substance that can be distinguished from the
absence of that substance (a blank value) with a stated confidence level
(generally 99%).
LOD or
Limit of
Detection is another consideration that
affects the detection limit is the
accuracy of the model used to predict concentration from the raw
analytical signal.
Limit of Quantitation or
LOQ
describes the smallest concentration of a substance that can be reliably
measured by an analytical procedure.
Quantitation
is to express something as a number,
measure
or quantity. To determine or measure the quantity of something.
Researchers solve a problem in organic chemistry. Scientists have
developed a strategy that could give a boost to the development of
pyridine-containing
drugs and organic functional materials. In chemicals used in agriculture,
as well as in pharmaceuticals and a variety of materials, pyridines are
often found as so-called functional units which decisively determine the
chemical properties of substances. Pyridines belong to the group of
ring-shaped carbon-hydrogen (C-H) compounds ("heterocycles"), and they
contain a nitrogen atom (N). For chemists, the direct functionalization
of the carbon-hydrogen bonds (C-H bonds) of pyridines is a
straightforward approach to designing and modifying complex molecules,
including in the final stage of the synthesis sequence.
Synthesis
Synthesis refers to
a
combination of two or more entities that together form something new;
alternately, it refers to the creating of something by artificial means,
or recreating or imitating a chemical compound or substance produced by a
living organism that is
natural and
found in
nature.
The process of producing a
chemical compound, usually by the union of
simpler chemical compounds.
Bonds -
Alchemy
-
Extraction
Biosynthesis is a multi-step, enzyme-catalyzed process where
substrates are converted into more complex products in living organisms.
In biosynthesis, simple compounds are modified, converted into other
compounds, or joined together to form macromolecules. This process often
consists of metabolic pathways. Some of these biosynthetic pathways are
located within a single cellular organelle, while others involve enzymes
that are located within multiple cellular organelles. Examples of these
biosynthetic pathways include the production of lipid membrane components
and nucleotides. The prerequisite elements for biosynthesis include:
precursor compounds, chemical energy (e.g. ATP), and catalytic enzymes
which may require coenzymes (e.g.NADH, NADPH). These elements create
monomers, the building blocks for macromolecules. Some important
biological macromolecules include: proteins, which are composed of amino
acid monomers joined via peptide bonds, and DNA molecules, which are
composed of nucleotides joined via phosphodiester bonds.
Waste Energy.
Synthetic Chemistry is the branch of
chemical science involved with developing means of making new chemicals
and developing improved ways of synthesizing existing chemicals. A key
aspect of green chemistry is the involvement of synthetic chemists in the
practice of environmental chemistry.
Green Chemistry or sustainable chemistry is an area of chemistry and
chemical engineering focused on the design of products and processes that
minimize or eliminate the use and generation of hazardous substances.
While environmental chemistry focuses on the effects of polluting
chemicals on nature, green chemistry focuses on the environmental impact
of chemistry, including lowering consumption of nonrenewable resources
and technological approaches for preventing pollution. The overarching
goals of green chemistry—namely, more resource-efficient and inherently
safer design of molecules, materials, products, and processes—can be
pursued in a wide range of contexts.
Environmental Chemistry is the scientific study of the chemical and
biochemical phenomena that occur in natural places. It should not be
confused with green chemistry, which seeks to reduce potential pollution
at its source. It can be defined as the study of the sources, reactions,
transport, effects, and fates of chemical species in the air, soil, and
water environments; and the effect of human activity and biological
activity on these. Environmental chemistry is an interdisciplinary
science that includes atmospheric, aquatic and soil chemistry, as well as
heavily relying on analytical chemistry and being related to
environmental and other areas of science. Environmental chemistry
involves first understanding how the uncontaminated environment works,
which chemicals in what concentrations are present naturally, and with
what effects. Without this it would be impossible to accurately study the
effects humans have on the environment through the release of chemicals.
Environmental chemists draw on a range of concepts from chemistry and
various environmental sciences to assist in their study of what is
happening to a chemical species in the environment. Important general
concepts from chemistry include understanding chemical reactions and
equations, solutions, units, sampling, and analytical techniques.
A radical new approach in synthetic chemistry. Scientists have
measured how unpaired electrons in atoms at one end of a molecule can
drive chemical reactivity on the molecule's opposite side. This work
shows how molecules containing these so-called free radicals could be
used in a whole new class of reactions. Most reactions involving free
radicals take place at the site of the unpaired electron. The Princeton
team had become experts in using free radicals for a range of synthetic
applications, such as polymer upcycling. But they've wondered whether
free radicals might influence reactivity on other parts of the molecule
as well, by pulling electrons away from those more distant locations. Our
measurements show that these radicals can exert powerful
'electron-withdrawing' effects that make other parts of the molecule more
reactive.
Chemical Synthesis is a purposeful execution of
chemical reactions to obtain a product, or several products. This
happens by physical and chemical manipulations usually involving one or
more reactions. In modern laboratory usage, this tends to imply that the
process is reproducible, reliable, and established to work in multiple
laboratories. A chemical synthesis begins by selection of compounds that
are known as reagents or reactants. Various reaction types can be applied
to these to synthesize the product, or an intermediate product. This
requires mixing the compounds in a reaction vessel such as a chemical
reactor or a simple round-bottom flask. Many reactions require some form
of work-up procedure before the final product is isolated. Chemical
synthesis is the construction of complex chemical compounds from simpler
ones. It is the process by which many substances important to daily life
are obtained.
Photosynthesis -
Electro-Chemistry
-
Synthetic Biology.
Protein Biosynthesis is the process whereby biological cells
generate new
proteins; it is balanced by the loss of cellular proteins
via degradation or export. Translation, the assembly of amino acids by
ribosomes, is an essential part of the biosynthetic pathway, along with
generation of messenger
RNA (mRNA),
aminoacylation of transfer RNA (tRNA), co-translational transport, and
post-translational modification. Protein biosynthesis is strictly
regulated at multiple steps. They are principally during transcription
(phenomena of RNA synthesis from DNA template) and translation (phenomena
of amino acid assembly from RNA).
Build Blocks of Life.
Protein Synthesis is the process of how
proteins are assembled from
amino
acids using information encoded in
genes. Each protein has its own unique
amino acid sequence that is specified by the
nucleotide sequence of the
gene encoding this protein. The genetic code is a set of three-nucleotide
sets called codons and each three-nucleotide combination designates an
amino acid, for example AUG (adenine-uracil-guanine) is the code for
methionine. Because DNA contains four nucleotides, the total number of
possible codons is 64; hence, there is some redundancy in the genetic
code, with some amino acids specified by more than one codon.
Simplified method makes
cell-free protein synthesis more flexible and accessible.
Amino Acids
Amino Acid are
biologically important organic compounds containing amine (-NH2) and
carboxyl (-COOH) functional groups, along with a side-chain (R group)
specific to each amino acid. The key elements of an amino acid are
carbon,
hydrogen,
oxygen, and
nitrogen, though other elements are found
in the side-chains of certain amino acids.
About 500 amino acids are
known (though only 20 appear in the
genetic code) and can be classified
in many ways. Nine proteinogenic amino acids are called "essential" for
humans because they cannot be created from other compounds by the human
body and so must be taken in as
food. Others may be conditionally
essential for certain ages or medical conditions. Essential amino acids
may also differ between species. Because of their biological
significance, amino acids are important in
nutrition and are commonly
used in
nutritional supplements, fertilizers, and food technology.
Industrial uses include the production of drugs, biodegradable plastics,
and chiral catalysts. Amino acids perform critical roles in processes
such as
neurotransmitter transport and
biosynthesis.
BCAA or Branched Chain Amino Acids. Amino
acids are the
building blocks of
protein. There are
nine
essential amino acids in total, but there's a key trio that helps
you maintain muscle: leucine, isoleucine, and valine. Of these three,
leucine is the muscle-building powerhouse. The beauty of BCAA supplements
is they can be easily used during
exercise to reduce fatigue, accelerate recovery, reduce
muscle
soreness, and improve the use of fat for
energy. BCAAs are well known for
triggering protein synthesis.
Leucine is an α-amino
acid used in the biosynthesis of proteins.
Isoleucine is an
α-amino acid that is used in the biosynthesis of proteins. It is
essential in humans, meaning
the body cannot
synthesize it, and must be ingested in our diet.
Valine is an α-amino
acid that is used in the biosynthesis of
proteins.
Human dietary sources are any proteinaceous foods such as meats, dairy
products, soy products, beans and legumes.
Vitamins -
Minerals -
Vegetables -
Building
Blocks of Life
Engineers create bacteria that can synthesize an unnatural amino acid.
In this study, the researchers focused on
para-nitro-L-phenylalanine (pN-Phe), a non-standard amino acid that
is neither one of the twenty standard amino acids nor been observed in
nature. pN-Phe has been used by other research groups to help the immune
system mount a response to proteins that it does not ordinarily respond
to. Researchers have engineered bacteria to synthesize an amino acid that
contains a rare functional group that others have shown to have
implications in the regulation of our immune system. The researchers also
taught a single bacterial strain to create the amino acid and place it at
specific sites within target proteins. These findings provide a
foundation for developing unique vaccines and immunotherapies in the
future. The Kunjapur Lab uses tools from synthetic biology and genetic
engineering to create micro-organisms that can synthesize different types
of compounds and molecules, especially ones with functional groups or
properties that are not well represented in nature.
New chemical process makes it easier to craft amino acids that don't
exist in nature. Chemists describe a powerful new way to create
new-to-nature, 'unnatural' amino acids, which could find use in
protein-based therapies and open up novel branches of organic chemistry.
Serine
is an α-amino acid that is used in the
biosynthesis of proteins. This compound is one of the naturally
occurring
proteinogenic amino acids. D-Serine also has been described as a
potential biomarker for early
Alzheimer's disease diagnosis, due to a relatively high concentration
of it in the cerebrospinal fluid of probable AD patients.
Enzymes.
Peptide
are natural biological or artificially manufactured
short chains of amino
acid monomers linked by peptide (amide) bonds.
Catalysis
Catalysis
is the increase in the rate of a
chemical reaction due to the
participation of an additional substance called a catalyst. In most
cases, reactions occur faster with a catalyst because they require less
activation energy. Furthermore, since they are not consumed in the
catalyzed reaction, catalysts can continue to act repeatedly. Often only
tiny amounts are required in principle.
Autocatalysis. A single chemical reaction is said to have
undergone autocatalysis, or be autocatalytic, if one of the reaction
products is also a reactant and therefore a catalyst in the same or a
coupled reaction. The reaction is called an autocatalytic reaction.
Photo-Catalysis.
Order of Reaction in chemical kinetics, the order of
reaction with respect to a given substance (such as reactant, catalyst or
product) is defined as the index, or exponent, to which its concentration term in the rate equation is raised.
Enzymes
Enzyme are
macromolecular biological catalysts. Enzymes accelerate
chemical reactions. The molecules upon which
enzymes may act are called substrates and the enzyme converts the
substrates into different molecules known as products. Almost all
metabolic processes in the cell need enzymes in order to occur at rates
fast enough to sustain life. The set of enzymes made in a cell
determines which metabolic pathways occur in that
cell. The study of
enzymes is called
enzymology and a new field of pseudoenzyme analysis has
recently grown up, recognizing that during evolution, some enzymes have
lost the ability to carry out biological catalysis, which is often
reflected in their
amino acid sequences and
unusual 'pseudocatalytic' properties.
Enzymes are known to catalyze more
than 5,000 biochemical reaction types. Most enzymes are
proteins, although a few are catalytic
RNA molecules. The
latter are called ribozymes. Enzymes' specificity comes from their unique
three-dimensional structures. Like all catalysts, enzymes increase the
reaction rate by lowering its activation energy. Some enzymes can make
their conversion of substrate to product occur many millions of times
faster. An extreme example is orotidine 5'-phosphate decarboxylase, which
allows a reaction that would otherwise take millions of years to occur in
milliseconds. Chemically, enzymes are like any catalyst and are not
consumed in chemical reactions, nor do they alter the equilibrium of a
reaction. Enzymes differ from most other catalysts by being much more
specific. Enzyme activity can be affected by other molecules: inhibitors
are molecules that decrease enzyme activity, and activators are molecules
that increase activity.
Many therapeutic drugs
and poisons are enzyme inhibitors. An enzyme's activity decreases
markedly outside its optimal
temperature and
pH. Some enzymes are
used commercially, for example, in the synthesis of antibiotics. Some
household products use enzymes to speed up chemical reactions: enzymes in
biological washing powders break down protein, starch or fat stains on
clothes, and enzymes in meat tenderizer break down proteins into smaller
molecules, making the meat easier to chew.
Six
types of enzymes are as follows: oxidoreductases, transferases,
hydrolases, lyases, isomerases, and ligases. Hydrolases are the most
common type, followed by oxioreductases and transferases. They account
for over half of the known enzymes.
Posphoglycerate dehydrogenase or PHGDH.
Enzyme Inhibitor is a molecule that binds to an enzyme and decreases
its activity. Since blocking an enzyme's activity
can kill a pathogen or
correct a metabolic imbalance,
many drugs are enzyme inhibitors. They are
also used in pesticides. Not all molecules that bind to enzymes are
inhibitors; enzyme activators bind to enzymes and increase their
enzymatic activity, while enzyme substrates bind and are converted to
products in the normal catalytic cycle of the enzyme.
Coenzyme is a small molecule essential for
the activity or functioning of some enzymes. (not a protein but sometimes
a vitamin).
Soluble
- Dietary Fiber
Cofactor is a substance that must join
with another to produce a given result. (as a coenzyme).
Cofactor in biochemistry is a non-protein chemical compound or
metallic ion that is required for a
Protein's biological activity to
happen. These proteins are commonly enzymes, and cofactors can be
considered "
helper molecules" that assist in biochemical transformations.
The rates at which this happen are characterized by enzyme kinetics.
Cofactors can be subclassified as either inorganic ions or complex
organic
molecules called
coenzymes, the
latter of which is mostly derived from vitamins and other
organic
essential nutrients in small amounts. A coenzyme that is tightly or even
covalently bound is termed a prosthetic group. Cosubstrates are
transiently bound to the protein and will be released at some point, then
get back in. The prosthetic groups, on the other hand, are bound
permanently to the protein. Both of them have the same function, which is
to facilitate the reaction of enzymes and
protein. Additionally, some
sources also limit the use of the term "cofactor" to inorganic
substances. An inactive enzyme without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is called a holoenzyme.
Some enzymes or enzyme complexes require several cofactors. For example,
the multienzyme complex pyruvate dehydrogenase at the junction of
glycolysis and the citric acid cycle requires five organic cofactors and
one metal ion: loosely bound thiamine pyrophosphate (TPP), covalently
bound lipoamide and flavin adenine dinucleotide (FAD), and the
cosubstrates nicotinamide adenine dinucleotide (NAD+) and coenzyme A
(CoA), and a metal ion (Mg2+). Organic cofactors are often vitamins or
made from vitamins. Many contain the nucleotide adenosine monophosphate
(AMP) as part of their structures, such as
ATP, coenzyme A, FAD, and NAD+.
This common structure may reflect a common evolutionary origin as part of
ribozymes in an ancient RNA world. It has been suggested that the AMP
part of the molecule can be considered to be a kind of "handle" by which
the enzyme can "grasp" the coenzyme to switch it between different
catalytic centers.
Cells and Longevity
The surprising Swiss-Army-knife-like functions of a powerful enzyme.
It acts as both a cleaver and a linking tool. Blue-green algae or
cyanobacteria have a superpower which likely helps them be highly
successful as invaders of waterways. They have an extraordinary ability
to store energy and nitrogen in their cells for times of need. But how
exactly they do so remains only partly understood. Now researchers have
uncovered an intriguing hitherto unknown ability of the enzymes (known as
cyanophycin synthetases) that are active in creating these food reserves.
Their findings are not only scientifically surprising, but take us a step
closer to being able to use these environmentally friendly polymers for
everything from bandages to biodegradable antiscalants to animal food.
Chemical
Kinetics also known as reaction kinetics, is the study of rates of
chemical processes. Chemical kinetics includes investigations of how
different experimental conditions can influence the speed of a chemical
reaction and yield information about the reaction's mechanism and
transition states, as well as the construction of mathematical models
that can describe the characteristics of a chemical reaction.
Petrochemical are chemical products derived from petroleum.
Some chemical compounds made from petroleum are also obtained from other
fossil fuels, such as coal or natural gas, or renewable sources such as
corn or
sugar cane.
Litmus
is a water soluble mixture of different dyes extracted from lichens. It
is often absorbed onto filter paper to produce one of the oldest forms of
pH indicator, used to test materials for acidity.
PH -
Water
Structural Formula of a chemical compound is a graphic
representation of the molecular structure, showing how the atoms are
arranged. The chemical bonding within the molecule is also shown, either
explicitly or implicitly. Unlike chemical formulas, which have a limited
number of symbols and are capable of only limited descriptive power,
structural formulas provide a complete geometric representation of the
molecular structure. For example, many chemical compounds exist in
different isomeric forms, which have different enantiomeric structures
but the same chemical formula. A structural formula is able to indicate
arrangements of atoms in three dimensional space in a way that a chemical
formula may not be able to do. Also known as
Representation in chemistry.
Unbalanced
Equation. Chemical equations usually do not come already
balanced. Therefore, we must finish our chemical reaction with as
many atoms of each element as when we started. Example #1: Balance the
following equation: H2 + O2 ---> H2O. It is an unbalanced equation
(sometimes also called a skeleton equation). A skeleton equation is just
a way of using the formulas to indicate the chemicals that were involved
in the chemical reaction. "Mg + O2 MgO." This skeleton equation shows
that magnesium reacts with oxygen to form magnesium oxide.
Nucleosynthesis is the process that creates new atomic
nuclei from pre-existing nucleons, primarily protons and neutrons.
Extraction
Extract
is a substance made by
extracting a part of a raw material, often by
using a solvent such as ethanol or water. Extracts may be sold as
tinctures, absolutes or in powder form. The aromatic principles of many
spices, nuts, herbs, fruits, etc., and some flowers, are marketed as
extracts, among the best known of true extracts being almond, cinnamon,
cloves, ginger, lemon, nutmeg, orange, peppermint, pistachio, rose,
spearmint, vanilla, violet, and wintergreen.
Bond.
Extraction in chemistry is a separation process consisting in the
separation of a substance from a matrix. It includes Liquid-liquid
extraction, and Solid phase extraction. The distribution of a solute
between two phases is an equilibrium condition described by partition
theory. This is based on exactly how the analyte move from the water into
an organic layer.
Synthesize.
Centrifuge is a machine with a rapidly rotating container that
applies centrifugal force to its contents, typically to separate fluids
of different densities (e.g., cream from milk) or liquids from solids. is
a piece of equipment that puts an object in rotation around a fixed axis
(spins it in a circle), applying a force perpendicular to the axis of
spin (outward) that can be very strong. The centrifuge works using the
sedimentation principle, where the centrifugal acceleration causes denser
substances and particles to move outward in the radial direction. At the
same time, objects that are less dense are displaced and move to the
center. In a laboratory centrifuge that uses sample tubes, the radial
acceleration causes denser particles to settle to the bottom of the tube,
while low-density substances rise to the top.
Separation Process is a method that converts a mixture or solution of
chemical substances into two or more distinct product mixtures. At least
one of results of the separation is enriched in one or more of the source
mixture's constituents. In some cases, a separation may fully divide the
mixture into pure constituents. Separations exploit differences in
chemical properties or physical properties (such as size, shape, mass,
density, or chemical affinity) between the constituents of a mixture.
Processes are often classified according to the particular differences
they use to achieve separation. If no single difference can be used to
accomplish a desired separation, multiple operations can often be
combined to achieve the desired end. With a few exceptions, elements or
compounds exist in nature in an impure state. Often these raw materials
must go through a separation before they can be put to productive use,
making separation techniques essential for the modern industrial economy.
The purpose of a separation may be analytical, can be used as a lie
components in the original mixture without any attempt to save the
fractions, or may be preparative, i.e. to "prepare" fractions or samples
of the components that can be saved. The separation can be done on a
small scale, effectively a laboratory scale for analytical or preparative
purposes, or on a large scale, effectively an industrial scale for
preparative purposes, or on some intermediate scale.
Filtering -
Membrane.
Dissociation in chemistry is a general process in which molecules (or
ionic compounds such as salts, or complexes)
separate or split into
smaller particles such as atoms, ions or radicals, usually in a
reversible manner. For instance, when an acid dissolves in water, a
covalent bond between an electronegative atom and a hydrogen atom is
broken by heterolytic fission, which gives a proton (H+) and a negative
ion. Dissociation is the opposite of association or recombination.
Molecular Diffusion is the thermal motion of all (liquid or
gas) particles at temperatures above absolute zero. The rate of this
movement is a function of temperature, viscosity of the fluid and the
size (mass) of the particles. Diffusion explains the net flux of
molecules from a region of higher concentration to one of lower
concentration. Once the concentrations are equal the molecules continue
to move, but since there is no concentration gradient the process of
molecular diffusion has ceased and is instead governed by the process of
self-diffusion, originating from the random motion of the molecules. The
result of diffusion is a gradual mixing of material such that the
distribution of molecules is uniform. Since the molecules are still in
motion, but an equilibrium has been established, the end result of
molecular diffusion is called a "dynamic equilibrium". In a phase with
uniform temperature, absent external net forces acting on the particles,
the diffusion process will eventually result in complete mixing.
Diffusion is the net movement of molecules or atoms from a
region of high concentration (or high chemical potential) to a region of
low concentration (or low chemical potential). This is also referred to
as the movement of a substance down a concentration gradient. A gradient
is the change in the value of a quantity (e.g., concentration, pressure,
temperature) with the change in another variable (usually distance). For
example, a change in concentration over a distance is called a
concentration gradient, a change in pressure over a distance is called a
pressure gradient, and a change in temperature over a distance is a
called a temperature gradient.
Soluble.
Intrinsic Properties and
Extrinsic Properties is a property of a system or of a
material itself or within. It is independent of how much of the material
is present and is independent of the form of the material, e.g., one
large piece or a collection of small particles. Intrinsic properties are
dependent mainly on the chemical composition or structure of the
material.
Quantitative Analysis is the determination of the absolute
or relative abundance (often expressed as a concentration) of one,
several or all particular substance(s) present in a sample.
Receptor is a protein molecule that receives chemical
signals from outside a cell. When such chemical signals bind to a
receptor, they cause some form of cellular/tissue response, e.g. a change
in the electrical activity of a cell. In this sense, a receptor is a
protein-molecule that recognizes and responds to endogenous chemical
signals, e.g. an acetylcholine receptor recognizes and responds to its
endogenous ligand, acetylcholine. However, sometimes in pharmacology, the
term is also used to include other proteins that are drug targets, such
as enzymes, transporters and ion channels.
Base Chemistry are substances that, in aqueous solution, are slippery
to the touch, taste astringent, change the color of indicators (e.g.,
turn red litmus paper blue), react with acids to form salts, promote
certain chemical reactions (base catalysis), accept protons from any
proton donor, and/or contain completely or partially displaceable OH−
ions. Examples of bases are the hydroxides of the alkali metals and
alkaline earth metals (NaOH, Ca(OH)2, etc.).
Elements - Periodic Table
Element is any
of the more than 100 known
substances, of which 92 occur naturally, that
cannot be separated into simpler substances and that singly or in
combination constitute all
matter. Each
element is distinguished by its
Atomic Number, which is the
number of protons
in the nuclei of its
atoms. Element can
also mean an abstract part of something. An artifact that is one of the
individual parts of which a
composite entity is made up; especially a
part that can be separated from or attached to a system.
Chemical
Element is a species of atoms having the same number of protons in
their atomic nuclei.
There are 118 elements that have been identified, of
which the first
94 occur naturally on Earth with the
remaining 24 being
synthetic elements. There are 80 elements that have at least one stable
isotope and 38 that have exclusively radioactive isotopes, which decay
over time into other elements. Iron is the most abundant element (by
mass) making up Earth, while
oxygen is the most common element in the
Earth's crust. Chemical elements constitute all of the ordinary matter of
the universe.
Elements are
atoms, the smallest piece that we can
split matter into, except for
subatomic particles and other things.
Elements often are stacked together with other elements to form
minerals.
Native elements that occur naturally are also considered minerals.
Native Element Minerals are those elements that occur in nature in
uncombined form with a distinct mineral structure. The elemental class
includes metals and intermetallic elements, naturally occurring alloys,
semi-metals and non-metals. The Nickel–Strunz classification system also
includes the naturally occurring phosphides, silicides, nitrides and
carbides.
It's amazing that when you add a
proton or remove a
proton from an element, you have a
totally different element.
Periodic Table is a
tabular arrangement of the
chemical elements, arranged by atomic number, electron configuration, and
recurring chemical properties, whose structure shows periodic trends.
Periodic is something happening or
recurring at
regular intervals.
Recurring or reappearing from
time to time.
Periodic Table of Elements
(image) -
Earth & Sky Chart
(image)
118 different Elements and more than 109 different types of
atom
- one for each element. Only the first 92 elements in the table are
naturally found.
Matter -
States -
Molecule -
Minerals -
Materials -
Transition Metals
Periodic Table of Elements (interactive)
Wiki Periodic Table (wiki) -
Natural Elements (wiki periodic table)
Videos of the
Periodic Table -
Tom Lehrer - The
Elements - LIVE FILM From Copenhagen in 1967 (youtube)
Chemical Library or compound library is a collection of stored
chemicals usually used ultimately in high-throughput screening or
industrial manufacture. The chemical library can consist in simple terms
of a series of stored chemicals. Each chemical has associated information
stored in some kind of database with information such as the chemical
structure, purity, quantity, and physiochemical characteristics of the
compound.
Compound Library is a collection
of chemicals that can be used for high-throughput screening and other
processes for
drug development. The
chemical compound characteristics, like
structure, purity, and quantity are usually stored chemical library
database for later use.
Synthetic Element is a chemical element that
does not occur naturally
on Earth, and can only be created artificially. So far, 24 synthetic
elements have been created (those with atomic numbers 95–118). All are
unstable, decaying with half-lives ranging from 15.6 million years to a
few hundred microseconds. Seven other elements were first created
artificially and thus considered synthetic, but later discovered to exist
naturally (in trace quantities) as well; among them
plutonium—first synthesized in 1940—the one best known to laypeople,
because of its use in atomic bombs and
nuclear reactors.
Chalcogen are the chemical elements in group 16 of the periodic
table. This group is also known as the oxygen family. It consists of the
elements oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and the
radioactive element polonium (Po). The chemically uncharacterized
synthetic element livermorium (Lv) is predicted to be a chalcogen as
well. Often, oxygen is treated separately from the other chalcogens,
sometimes even excluded from the scope of the term "chalcogen"
altogether, due to its very different chemical behavior from sulfur,
selenium, tellurium, and polonium. The word "chalcogen" is derived from a
combination of the Greek word khalkόs (χαλκός) principally meaning copper
(the term was also used for bronze/brass, any metal in the poetic sense,
ore or coin), and the Latinised Greek word genēs, meaning born or
produced.
Monatomic Gas
means "single
atom." It is usually applied to
gases: a monatomic gas is
one in which atoms are not bound to each other. All chemical elements
will be monatomic in the gas phase at sufficiently high temperatures. The
thermodynamic behavior of monatomic gas is extremely simple when compared
to polyatomic gases because it is free of any rotational or vibrational
energy.
Diatomic are molecules composed of only two atoms, of the same or
different chemical elements.
Noble Gas are all odorless, colorless, monatomic gases with
very low chemical reactivity. The six noble gases that occur naturally
are
helium (He),
neon (Ne),
argon (Ar),
krypton (Kr),
xenon (Xe), and the
radioactive radon (Rn).
Oganesson (Og) is predicted to be a noble gas as
well, but its chemistry has not yet been investigated.
Helium is a chemical
element with symbol He and
atomic number 2. It is a colorless, odorless,
tasteless, non-toxic, inert, monatomic gas, the first in the noble gas
group in the periodic table. Its
boiling point is the lowest among all
the elements. After
hydrogen, helium is the second lightest and second
most abundant element in the observable universe, being present at about
24% of the total elemental mass, which is more than 12 times the mass of
all the heavier elements combined. Its abundance is similar to this
figure in the Sun and in Jupiter. This is due to the very high nuclear
binding energy (per nucleon) of helium-4 with respect to the next three
elements after helium. This helium-4 binding energy also accounts for why
it is a product of both nuclear fusion and
radioactive decay. Most helium
in the universe is helium-4, and is believed to have been formed during
the Big Bang. Large amounts of new helium are being created by
nuclear
fusion of hydrogen in
stars.
A Tour of
the Periodic Table (youtube)
Periodic Table of
Elements - Chemistry: A Volatile History - BBC Four (youtube)
Investigating the
Periodic Table with Experiments - with Peter Wothers (youtube)
Ununseptium
Uus element 117 -
PAI Polyatomic
Ion
Relative Atomic Mass is a dimensionless physical quantity,
the ratio of the average
mass of atoms of an element (from a single given
sample or source) to 1⁄12 of the mass of an atom of
carbon-12 (known as
the unified atomic mass unit).
Actinide
series encompasses the 15 metallic chemical elements with atomic numbers
from 89 to 103, actinium through lawrencium.
Lanthanide comprises the
15 metallic chemical elements with atomic
numbers 57–71, from lanthanum through lutetium. These elements, along
with the chemically similar elements scandium and yttrium, are often
collectively known as the rare earth elements.
Electron Configuration
is the distribution of
electrons of
an atom or molecule (or other physical structure) in atomic or molecular
orbitals.
Resonance is a way of describing
delocalized electrons
within certain molecules or polyatomic ions where the bonding cannot be
expressed by one single Lewis structure. A molecule or ion with such
delocalized electrons is represented by several contributing structures
(also called resonance structures or canonical structures).
Classical Elements refer to
water,
earth,
fire,
air, and later
aether, which were proposed to explain the
nature and complexity of all matter in terms of simpler substances.
Four States of Matter.
Prayer Flag colors signifies
5 elements that are always arranged in a
specific order, from left to right:
blue, white, red, green, yellow. Blue
represents the
sky, white represents the
air, red symbolizes
fire, green symbolizes
water, and yellow symbolizes
earth. All five colors together signify
balance. Traditionally,
prayer flags are used to promote peace,
compassion, strength, wisdom and good will, that is blown by the wind to
spread into all pervading space.
Ether -
Pentagram.
Nova explosions alone cannot explain amount of lithium in current
universe. A new study of lithium production in a classical nova found
a production rate of only a couple of percent that seen in other
examples. This shows that there is a large diversity within classical
novae and implies that nova explosions alone cannot explain the amount of
lithium seen in the current Universe. This is an important result for
understanding both the explosion mechanism of classical novae and the
overall chemical evolution of the Universe.
Minerals
Mineral by definition,
is any
naturally occurring,
inorganic substance, often additionally
characterized by an exact crystal structure. A solid homogeneous
inorganic substances occurring in nature having a definite chemical
composition. Its chemical structure can be exact, or can vary within
limits.
Minerals and Metals in
Food -
Web Mineral
Biomineralization is the process by which living organisms produce
minerals, often to harden or stiffen existing tissues. Such tissues are
called mineralized tissues.
Native
Metal
is any
metal that is found in its metallic form, either pure or as an
alloy, in nature.
Alloy is a
mixture
of metals or a mixture of a metal and another element. Alloys are defined
by a metallic bonding character.
Nonmetal
is a chemical element that mostly lacks metallic attributes. Physically,
nonmetals tend to be highly volatile (easily vaporized), have low
elasticity, and are good
insulators of heat
and electricity; chemically, they tend to have high ionization energy and
electronegativity values, and gain or share electrons when they react
with other elements or compounds. Seventeen elements are generally
classified as nonmetals; most are gases (hydrogen, helium, nitrogen,
oxygen, fluorine, neon, chlorine, argon, krypton, xenon and radon); one
is a liquid (bromine), and a few are solids (carbon, phosphorus, sulfur,
selenium, and iodine).
Graphene.
Metalloid is any chemical element which has properties in between
those of metals and nonmetals, or that has a mixture of them. There is
neither a standard definition of a metalloid nor complete agreement on
the elements appropriately classified as such. Despite the lack of
specificity, the term remains in use in the literature of chemistry.
Rocks are a composed of one or more minerals.
Rocks -
Rare Earth Minerals
-
Mining -
Metallurgy -
Alchemy -
Materials
Classical Element typically refers to the concepts in ancient Greece
of
earth,
water,
air,
fire, and (later) aether, which were
proposed to explain the nature and complexity of all matter in terms of
simpler substances.
Aether classical element is the material that fills the region of the
universe above the terrestrial sphere.
Atomic Spectroscopy is the study of the electromagnetic radiation
absorbed and emitted by atoms. Since unique elements have characteristic
(signature) spectra, atomic spectroscopy, specifically the
electromagnetic spectrum
or mass spectrum, is applied for determination of elemental compositions.
It can be divided by atomization source or by the type of
spectroscopy used. In the latter case,
the main division is between optical and mass spectrometry. Mass
spectrometry generally gives significantly better analytical performance,
but is also significantly more complex. This complexity translates into
higher purchase costs, higher operational costs, more operator training,
and a greater number of components that can potentially fail. Because
optical spectroscopy is often less expensive and has performance adequate
for many tasks, it is far more common. Atomic absorption spectrometers
are one of the most commonly sold and used analytical devices. When atoms
are excited they emit light of certain wavelengths which correspond to
different colors. The emitted light can be observed as a series of
colored lines with dark spaces in between; this series of colored lines
is called a line or atomic spectra. Each element produces a unique set of
spectral lines.
Emission Spectrum of a
chemical element or
chemical compound is the spectrum of frequencies of electromagnetic
radiation emitted due to an atom or molecule making a transition from a
high energy state to a lower energy state. The photon energy of the
emitted photon is equal to the energy difference between the two states.
There are many possible electron transitions for each atom, and each
transition has a specific energy difference. This collection of different
transitions, leading to different radiated wavelengths, make up an
emission spectrum. Each element's emission spectrum is unique. Therefore,
spectroscopy can be used to identify the elements in matter of unknown
composition. Similarly, the emission spectra of molecules can be used in
chemical analysis of substances.
Atomic Emission Spectroscopy is a method of chemical analysis that
uses the intensity of light emitted from a flame, plasma, arc, or spark
at a particular wavelength to determine the quantity of an element in a
sample. The wavelength of the atomic spectral line in the emission
spectrum gives the identity of the element while the intensity of the
emitted light is proportional to the number of atoms of the element.
Atomic Absorption Spectroscopy is a spectroanalytical procedure for
the quantitative determination of chemical elements using the absorption
of optical radiation (light) by free atoms in the gaseous state. Atomic
absorption spectroscopy is based on absorption of light by free metallic
ions. In analytical chemistry the technique is used for determining the
concentration of a particular element (the analyte) in a sample to be
analyzed. AAS can be used to determine over 70 different elements in
solution, or directly in solid samples via electrothermal vaporization,
and is used in pharmacology, biophysics, archaeology and toxicology
research.
Molecules
Molecule is
formed when two or more
atoms join together
chemically.
All molecules are in constant
motion. Molecules
of a
liquid have more freedom of
movement than those in a solid. Molecules in a gas have the greatest
degree of motion.
Heat, temperature and the
motion of molecules are all related.
Temperature is a measure of the
average
kinetic energy of the molecules
in a material.
Nano Size -
Color -
Signaling Molecules -
Symmetry
Macromolecule is a very large molecule, such as protein, commonly
created by the polymerization of smaller subunits (monomers). They are
typically composed of thousands of atoms or more. The most common
macromolecules in biochemistry are biopolymers (nucleic acids, proteins,
carbohydrates and lipids) and large non-polymeric molecules (such as
lipids and macrocycles). Synthetic macromolecules include common plastics
and synthetic fibers as well as experimental materials such as carbon
nanotubes.
The smallest molecule is the
diatomic hydrogen (H2), with a bond length of 0.74 Å. Effective molecular
radius is the size a molecule displays in solution.
Small Molecule or micromolecule is a low molecular weight (≤ 1000
daltons) organic compound that may regulate a biological process,
with a size on the order of
1 nm.
Many drugs are small molecules; the terms are equivalent in the
literature. Larger structures such as nucleic acids and proteins, and
many polysaccharides are not small molecules, although their constituent
monomers (ribo- or deoxyribonucleotides, amino acids, and monosaccharides,
respectively) are often considered small molecules. Small molecules may
be used as research tools to probe biological function as well as leads
in the development of new therapeutic agents. Some can inhibit a specific
function of a protein or disrupt protein–protein interactions.
Metabolites.
Diatomic
Molecule are molecules composed of only
two atoms, of the same or
different chemical elements.
Binary Compound.
Dyad is something that consists of two
elements or parts.
Heteronuclear Molecule is a molecule
composed
of atoms of more than one chemical element. For example, a
molecule of water (H2O) is heteronuclear because it has
atoms of two different elements,
hydrogen (H) and oxygen (O). Similarly, a heteronuclear ion is an ion
that contains atoms of more than one
chemical element.
For example, the carbonate ion (CO32−) is heteronuclear because it has
atoms of carbon (C) and oxygen (O). The lightest heteronuclear ion is the
helium hydride ion (HeH+). This is in contrast to a homonuclear ion,
which contains all the same kind of atom, such as the dihydrogen cation,
or atomic ions that only contain one atom such as the hydrogen anion
(H−).
Biomolecule is molecule that is present in living
organisms, including
large macromolecules such as
proteins,
carbohydrates, lipids, and
nucleic acids, as well as small molecules such as primary metabolites,
secondary metabolites, and natural products. A more general name for
this class of material is biological materials. Biomolecules are usually
endogenous but may also be exogenous. For example, pharmaceutical drugs
may be natural products or semisynthetic (biopharmaceuticals) or they
may be totally synthetic.
Compounds.
Researchers discover 'neutronic molecules'. Study shows neutrons can
bind to nanoscale atomic clusters known as quantum dots. The finding may
provide insights into material properties and quantum effects.
Neutrons are subatomic particles that
have no electric charge, unlike protons and electrons. That means that
while the electromagnetic force is responsible for most of the
interactions between radiation and materials, neutrons are essentially
immune to that force.
Molecular Geometry is the
three-dimensional arrangement of the
atoms that constitute a molecule. It includes the general
shape of the molecule as well as bond
lengths, bond angles, torsional angles and any other
geometrical parameters that determine
the position of each atom. Molecular geometry influences several
properties of a substance including its reactivity, polarity,
phase of matter, color, magnetism and
biological activity. The angles between
bonds that an
atom forms depend only weakly on the rest of molecule, i.e. they can be
understood as approximately local and hence transferable properties.
Molecular
Dynamics is a computer simulation method for studying the physical
movements of atoms and molecules, and is thus a type of N-body
simulation. The atoms and
molecules are allowed to interact for a fixed period of time, giving a
view of the dynamic evolution of the system. In the most common version,
the trajectories of atoms and molecules are determined by numerically
solving Newton's equations of
motion for a system
of interacting particles, where forces between the particles and their
potential energies are calculated using interatomic potentials or
molecular mechanics force fields. The method was originally developed
within the field of theoretical physics in the late 1950s but is applied
today mostly in chemical physics, materials science and the modelling of
biomolecules.
Differential Equations.
Molecular Engineering is
the design and testing of molecular properties, behavior and interactions
in order to assemble better materials, systems, and processes for
specific functions. This approach, in which observable properties of a
macroscopic system are influenced by direct alteration of a molecular
structure, falls into the broader category of “bottom-up” design.
Nucleotide are
organic molecules that serve as the monomers, or subunits, of nucleic
acids like
DNA and RNA. The building
blocks of nucleic acids, nucleotides are composed of a nitrogenous base,
a five-carbon sugar (ribose or deoxyribose), and at least one phosphate
group. Thus a nucleoside plus a phosphate group yields a nucleotide.
Molecular Biology concerns the molecular basis of biological
activity between biomolecules in the various systems of a cell, including
the interactions between DNA, RNA, and proteins and their biosynthesis,
as well as the regulation of these interactions.
Automated Small-Molecule Synthesis
Innovative experimental scheme can create tailor-made mirror molecules.
The technique can make ordinary molecules spin so fast that they lose
their normal symmetry and shape and instead form mirrored versions of
each other.
How molecules in cells
'find' one another and organize into structures. It's critical that
the cell undergo a liquid-liquid phase separation in order for two
different biological process to occur.
Using ions to find molecules. When we think of ions, we usually think
of single atoms that have lost or gained some electrons, but entire
molecules can also become
ions. Physicists
now show that cold molecular ions can be created using a new method, and
that they are a very useful tool for detecting small amounts of other,
regular molecules.
An ion is an atom or
molecule with a surplus or shortage of electrons. Being charged
particles, ions can be 'trapped' by
electromagnetic fields: it is easy to keep them in a fixed position.
Trapped ions constitute a promising platform for
quantum computation. The reason for
this is that they can be stored for a long time, and that modern lasers
allow physicists to control single ions very precisely. These properties
also make trapped ions into prime candidates to study chemical reactions,
especially when they are immersed in a bath of regular atoms or
molecules.
Powerful method probes small-Molecule Structures. Small molecules --
from naturally occurring metabolites and hormones to synthetic medicines
and pesticides -- can have big effects on living things. But for
scientists to understand how the molecules work and how to design
beneficial ones, they need to know the precise arrangement of atoms and
chemical bonds. Now researchers have found a faster, simpler and
potentially more reliable way to solve the structures of small molecules.
Currently, the gold standard for determining small-molecule structures is
X-ray crystallography. In this technique, researchers crystallize a small
molecule and then bombard the crystal with X-rays, which diffract in
complex patterns that reveal the molecule's 3D structure. However,
producing large, high-quality crystals is time-consuming or impossible
for many compounds. Researchers wondered if they could use a form of
cryoelectron microscopy to characterize
small molecules. Known as microcrystal-electron diffraction (MicroED),
this technique was developed 5 years ago to study protein structures. In
this technique, electron beams, instead of X-rays, are diffracted from
crystals, which can be much smaller than those required for X-ray
crystallography.The researchers first tested MicroED on a sample of
powdered progesterone, which contained thousands of nanocrystals. They
rotated a single crystal and collected electron diffraction data from
different angles, determining the structure of the hormone at high
resolution (1 angstrom) in less than 30 minutes, compared with weeks or
months for X-ray crystallography. They went on to successfully
characterize 11 other natural, synthetic and pharmaceutical products,
including acetaminophen, ibuprofen and several antibiotics. The
researchers even identified four different molecules in a mixture by
studying individual nanocrystals. Using MicroED, the researchers analyzed
crystals that were a billionth of the size typically needed for X-ray
crystallography. The rapid, precise method has the potential to greatly
accelerate research in the fields of synthetic chemistry, natural product
chemistry and drug discovery, the researchers say.
Astronomers discover largest molecule yet in a planet-forming disc.
Array (ALMA) in Chile, researchers have for the first time detected
dimethyl ether in a planet-forming disc. With
nine atoms, this is the largest molecule identified in such a disc
to date. It is also a precursor of larger organic molecules that can lead
to the emergence of life. The molecules were found in the planet-forming
disc around the young star IRS 48 (also known as Oph-IRS 48) with the
help of ALMA, an observatory co-owned by the European Southern
Observatory (ESO). IRS 48, located 444 light-years away in the
constellation Ophiuchus, has been the subject of numerous studies because
its disc contains an asymmetric, cashew-nut-shaped "dust trap." This
region, which likely formed as a result of a newly born planet or small
companion star located between the star and the dust trap, retains large
numbers of millimetre-sized dust grains that can come together and grow
into kilometre-sized objects like comets, asteroids and potentially even
planets.
Polymers
Polymer
is a
large molecule, or macromolecule, composed of
many repeated
subunits. Because of their broad range of properties, both synthetic and
natural polymers play an essential and ubiquitous role in everyday life.
Polymers range from familiar synthetic plastics such as polystyrene to
natural biopolymers such as DNA and proteins that are fundamental to
biological structure and function. Polymers, both natural and synthetic,
are created via
polymerization of many small molecules, known as
monomers. Their consequently large molecular mass relative to small
molecule compounds produces unique physical properties, including
toughness,
viscoelasticity, and a tendency to form glasses and semicrystalline structures rather than crystals.
Plastic
is material consisting of any of a wide range of synthetic or
semi-synthetic
organic compounds that are
malleable and so can be
molded
into solid objects.
Biopolymer are
polymers produced by living organisms; in other words, they are
polymeric
biomolecules. Since they are polymers, biopolymers contain monomeric
units that are covalently bonded to form larger structures. There are
three main classes of biopolymers, classified according to the monomeric
units used and the structure of the biopolymer formed: polynucleotides (
RNA
and DNA), which are long polymers composed of 13 or more nucleotide
monomers; polypeptides, which are short polymers of amino acids; and
polysaccharides, which are often linear bonded polymeric carbohydrate
structures. Other examples of biopolymers include rubber, suberin,
melanin and lignin.
Bio-Plastics -
Material Science -
Smart Polymers -
Graphene
Two
Dimensional Polymer is a sheet-like monomolecular macromolecule
consisting of laterally connected repeat units with end groups along all
edges. This recent definition of 2DP is based on Hermann Staudinger's
polymer concept from the 1920s. According to this, covalent long chain
molecules ("Makromoleküle") do exist and are composed of a sequence of
linearly connected repeat units and end groups at both termini. Moving
from one dimension to two offers access to surface morphologies such as
increased surface area, porous membranes, and possibly in-plane pi
orbital-conjugation for enhanced electronic properties. They are distinct
from other families of polymers because 2D polymers can be isolated as
multilayer crystals or as individual sheets. The term 2D polymer has also
been used more broadly to include linear polymerizations performed at
interfaces, layered non-covalent assemblies, or to irregularly
cross-linked polymers confined to surfaces or layered films. 2D polymers
can be organized based on these methods of linking (monomer interaction):
covalently linked monomers, coordination polymers and supramolecular
polymers. Topologically, 2DPs may thus be understood as structures made
up from regularly tessellated regular polygons (the repeat units). Figure
1 displays the key features of a linear and a 2DP according to this
definition. For usage of the term "2D polymer" in a wider sense, see
"History".
New lightweight material is stronger than steel.
Supramolecular Polymers is a polymer whose monomer repeat units are
held together by noncovalent bonds. Non-covalent forces that hold
supramolecular polymers together include coordination, π-π interactions,
and hydrogen bonding. Supramolecular polymers can have physical
properties similar to plastic materials, while having better
processability and better recycling and self-healing properties, thanks
to their reversible transition from monomer to polymer structure.
Method to change fundamental architecture of polymers. A research
team has developed methods to manipulate polymers in a way that changes
their fundamental structure, paving the way for potential applications in
cargo delivery and release, recyclable materials, shape-shifting soft
robots, antimicrobials and more.
Single-Nucleotide Polymorphism is a variation in a single nucleotide
that occurs at a specific position in the
genome, where each variation is
present to some appreciable degree within a population.
Monomer is a molecule
that may bind chemically or supramolecularly to other molecules to form a
(supramolecular) polymer.
Polymerization is any process in which
relatively small
molecules, called monomers,
combine chemically to produce a very large chainlike or network molecule,
called a polymer. The monomer molecules may be all alike, or they may
represent two, three, or more different compounds.
Photopolymer is a polymer that changes its properties when
exposed to
light, often in the ultraviolet or visible region of the electromagnetic
spectrum. These changes are often manifested structurally, for example
hardening of the material occurs as a result of cross-linking when
exposed to light. An example is shown below depicting a mixture of
monomers, oligomers, and photoinitiators that conform into a hardened
polymeric material through a process called curing. A wide variety of
technologically useful applications rely on photopolymers, for example
some enamels and varnishes depend on photopolymer formulation for proper
hardening upon exposure to light. In some instances, an enamel can cure
in a fraction of a second when exposed to light, as opposed to thermally
cured enamels which can require half an hour or longer. Curable materials
are widely used for medical, printing, and photoresist technologies.
3D Printing.
Development of an easy-to-synthesize self-healing gel composed of
entangled ultrahigh molecular weight polymers. Circular-economy-friendly
gel may be used in durable flexible devices. A research team has
developed a method for easily synthesizing a self-healing polymer gel
made of ultrahigh molecular weight polymers (polymers with a molecular
weight greater than 106 g/mol) and non-volatile ionic liquids. This
recyclable and self-healable polymer gel is compatible with circular
economy principles. In addition, it may potentially be used as a durable,
ionically conductive material for flexible IoT devices.
Bonds - Attractions
Chemical Bond is a lasting attraction between
atoms that
enables the
formation of chemical compounds. The bond may result from the
electrostatic force of attraction between atoms with opposite charges, or
through the
sharing of electrons as in the covalent bonds. The strength
of chemical bonds varies considerably; there are "
strong bonds" or
"primary bond" such as metallic, covalent or ionic bonds and "
weak bonds"
or "secondary bond" such as
Dipole-dipole interaction, the London
dispersion force and hydrogen bonding.
Why form chemical bonds? One answer is that atoms are trying to
reach the most stable (lowest-energy) state that they can. Many atoms
become stable when their
valence shell
is filled with electrons or when they satisfy the
octet rule by having
eight valence electrons. If atoms don’t have this arrangement, they’ll
“want” to reach it by gaining, losing, or
sharing electrons via bonds.
Molecular Binding is an
attractive interaction
between two molecules that results in a
stable association in which the molecules are in close proximity to
each other. It often but not always involves some chemical bonding.
Bind is to fasten, attach, tie, wrap
or stick things firmly
together.
Binding Energy -
Commitment -
Metal-Binding
ProteinsBond is an
electrical force
linking atoms. A
connection
that fastens things together. The property of
sticking together.
Bound in chemistry is to form a
chemical bond with with another element. Bound in physics is something
being held with another element, substance or material in chemical or
physical union. Bound in computing is to associate an identifier with a
value or object. Bound can also mean remain stuck to or to keep in place.
To form the boundary of something; To be contiguous to. A line
determining the limits of an area. The line or plane indicating the limit
or extent of something. The greatest possible degree of something. Wrap
around with something so as to cover or enclose. Fasten or secure with a
rope, string, or cord. To walk or run with leaping strides. A leaping
movement upward.
Metallic Bonding is a type of chemical bonding that rises from the
electrostatic attractive force between conduction electrons (in the form
of an electron cloud of delocalized electrons) and positively charged
metal ions. It may be described as the sharing of free electrons among a
structure of positively charged ions (cations). Metallic bonding accounts
for many physical properties of metals, such as strength, ductility,
thermal and electrical resistivity and conductivity, opacity, and luster.
Covalent Bond
also called a
molecular bond, is a chemical bond that involves the
sharing of
electron pairs between atoms. These electron pairs are known
as
shared pairs or bonding pairs, and the stable balance of attractive
and repulsive forces between atoms, when they
share electrons, is known
as covalent bonding. For many
molecules, the
sharing of electrons allows
each atom to attain the equivalent of a full outer shell, corresponding
to a stable electronic configuration.
Strong bonds hold molecules
together and the weaker bonds create temporary connections.
Peptide Bond is a chemical bond formed between two molecules when the
carboxyl group of one molecule reacts with the amino group of the other
molecule, releasing a molecule of
water or H2O.
A peptide bond is an amide type of covalent chemical bond linking two
consecutive alpha-amino acids from C1 (carbon number one) of one
alpha-amino acid and N2 (nitrogen number two) of another, along a peptide
or protein chain. It can also be called a eupeptide bond to distinguish
it from an isopeptide bond, which is another type of amide bond between
two
amino acids. When two amino acids form a
dipeptide through a peptide bond, it is a type of condensation reaction.
In this kind of condensation, two amino acids approach each other, with
the non-side chain (C1) carboxylic acid moiety of one coming near the
non-side chain (N2) amino moiety of the other. One loses a hydrogen and
oxygen from its carboxyl group (COOH) and the other loses a hydrogen from
its amino group (NH2). This reaction produces a molecule of water (H2O)
and two amino acids joined by a peptide bond (−CO−NH−). The two joined
amino acids are called a dipeptide. The amide bond is synthesized when
the carboxyl group of one amino acid molecule reacts with the amino group
of the other amino acid molecule, causing the release of a molecule of
water or
H2O, hence the process is a dehydration
synthesis reaction. The formation of the peptide bond consumes energy,
which, in organisms, is derived from
ATP.
Peptides and
proteins are chains of
amino acids held together by peptide bonds (and sometimes by a few
isopeptide bonds). Organisms use
enzymes to produce
nonribosomal peptides, and
ribosomes to produce proteins via reactions that differ in details
from dehydration
synthesis. Some peptides, like
alpha-amanitin, are called ribosomal peptides as they are made by
ribosomes, but many are nonribosomal peptides as they are synthesized by
specialized enzymes rather than ribosomes. For example, the tripeptide
glutathione is synthesized in two steps from free amino acids, by two
enzymes: glutamate–cysteine ligase (forms an isopeptide bond, which is
not a peptide bond) and glutathione synthetase (forms a peptide bond).
Ionic Bonding is a type of chemical bonding that involves the
electrostatic attraction between oppositely charged
ions, and is the
primary interaction occurring in ionic compounds. It is one of the main
bonds along with Covalent bond and Metallic bonding. Ions are atoms that
have gained one or more electrons (known as anions, which are negatively
charged) and atoms that have lost one or more electrons (known as
cations,
which are positively charged). This transfer of electrons is known as
electrovalence in contrast to covalence. In the simplest case, the cation
is a metal atom and the anion is a nonmetal atom, but these ions can be
of a more complex nature, e.g. molecular ions like NH+4 or SO2−4. In
simpler words, an ionic bond is the transfer of electrons from a metal to
a non-metal in order to obtain a full valence shell for both atoms.
Zero Point Energy.
Chemical Affinity is the electronic property by which dissimilar
chemical species are capable of forming chemical compounds. Chemical
affinity can also refer to the tendency of an atom or compound to combine
by chemical reaction with atoms or compounds of unlike composition.
When an
electron moves from one atom
to another, both atoms become
ions. An
ionic bond is formed when two ions of opposite charge come together by
attraction, NOT when an electron is transferred. Think of ionic bond
formation as the second step in a two step process: Two atoms each become
ions. Covalent bonding occurs when pairs of electrons are shared by
atoms. Atoms will covalently bond with other atoms in order to gain more
stability, which is
gained by forming a full
electron shell. By sharing their outer most (valence) electrons,
atoms can fill up their outer electron shell and gain stability. When a
covalent bond is formed, the
electrons do still
continue to revolve around the nucleus in orbitals, however a new
kind of orbital is formed which are called molecular orbitals, rather
than an
atomic orbital.
Atomic Orbital is a mathematical function describing the location and
wave-like behavior of an
electron in an
atom. This function can be used to
calculate the probability of finding any electron of an atom in any
specific region around the atom's nucleus. The term atomic
orbital may also refer to the physical
region or space where the electron can be calculated to be present, as
predicted by the particular mathematical form of the orbital.
S orbital is spherically symmetric around
the nucleus of the atom, like a hollow ball made of rather fluffy
material with the nucleus at its centre.
P
orbital is a dumbbell-shaped or lobed region describing where an
electron can be found, within a certain degree of probability. The node
of the dumbbell occurs at the atomic nucleus, so the probability of
finding an electron in the nucleus is very low (but not zero).
sp2 hybridization is the mixing of one s
and two p atomic orbitals, which involves the promotion of one electron
in the s orbital to one of the 2p atomic orbitals. The combination of
these atomic orbitals creates three new hybrid orbitals equal in
energy-level.
Carbon 12 -
Hexogon.
Orbital Hybridisation is the concept of mixing
atomic orbitals
into new hybrid orbitals (with different energies, shapes, etc., than the
component atomic orbitals) suitable for the pairing of electrons to form
chemical bonds in valence bond theory. Hybrid orbitals are very useful in
the explanation of molecular geometry and
atomic bonding properties.
Although sometimes taught together with the valence shell electron-pair
repulsion (VSEPR) theory, valence bond and hybridisation are in fact not
related to the VSEPR model.
Molecular Orbital is a mathematical function describing the location
and
wave-like behavior of an
electron in a
molecule. This function can be used
to calculate chemical and physical properties such as the probability of
finding an electron in any specific region. When multiple atoms combine
chemically into a molecule, the electrons' locations are determined by
the molecule as a whole, so the atomic orbitals combine to form molecular
orbitals. The electrons from the constituent atoms occupy the molecular
orbitals. Mathematically, molecular orbitals are an approximate solution
to the Schrodinger equation for the electrons in the field of the
molecule's atomic nuclei. They are usually constructed by combining
atomic orbitals or hybrid orbitals from each atom of the molecule, or
other molecular orbitals from groups of atoms. They can be quantitatively
calculated using the Hartree–Fock or self-consistent field (SCF) methods.
Molecular orbitals are of three types: bonding orbitals which have an
energy lower than the energy of the atomic orbitals which formed them,
and thus promote the chemical bonds which hold the molecule together;
antibonding orbitals which have an energy higher than the energy of their
constituent atomic orbitals, and so oppose the bonding of the molecule,
and nonbonding orbitals which have the same energy as their constituent
atomic orbitals and thus have no effect on the bonding of the molecule.
Anti-Bonding Molecular Orbital is a type of molecular orbital
that
weakens the chemical bond between two
atoms and helps to raise the energy of the molecule relative to the
separated atoms. Such an orbital has one or more nodes in the bonding
region between the nuclei. The density of the electrons in the orbital is
concentrated outside the bonding region and acts to pull one nucleus away
from the other and tends to cause mutual repulsion between the two atoms.
This is in contrast to a bonding molecular orbital, which has a lower
energy than that of the separate atoms, and is responsible for chemical
bonds.
Bonding
Molecular Orbital describes the attractive interactions between the
atomic orbitals of two or more atoms in a molecule. In MO theory,
electrons are portrayed to move in waves. When more than one of these
waves come close together, the in-phase combination of these waves
produces an interaction that leads to a species that is greatly
stabilized. The result of the waves’ constructive interference causes the
density of the electrons to be found within the binding region, creating
a
stable bond between the two species.
Carbon 12.
Repulsive Force is the force by which
bodies repel one another.
Repel is to
cause something to move back or move away by force or influence.
Forces.
Attractive Force is the force by which one object attracts
another. There are numerous attractive forces prevailing in nature. Some
of them are magnetic force, electric force, electrostatic force and
gravitational force.
Attract is causing
something to move closer or approach, and prevent it from moving away
using the force of attraction.
Valence is the combining power of an element, especially as measured
by the number of
hydrogen atoms it can
displace or combine with. Valence in
biology
is the relative capacity to unite or react or interact as with antigens
or a biological substrate.
Intermolecular Force are the
forces which
mediate interaction between molecules, including forces of
attraction or repulsion which act between molecules and other types of
neighboring particles, e.g., atoms or ions. Intermolecular forces are
weak relative to intramolecular forces – the forces which hold a
molecule together. For example, the covalent bond, involving
sharing electron pairs between atoms, is
much stronger than the forces present between neighboring molecules. Both
sets of forces are essential parts of force fields frequently used in
molecular mechanics. The investigation of intermolecular forces starts
from
macroscopic observations which
indicate the existence and action of forces at a molecular level. These
observations include non-ideal-gas thermodynamic behavior reflected by
virial coefficients, vapor pressure,
viscosity, superficial tension, and absorption data.
Amazing Properties of Water.
Intramolecular Force is any force that binds together the atoms
making up a molecule or compound, not to be confused with intermolecular
forces, which are the forces present between molecules. The subtle
difference in the name comes from the Latin roots of English with inter
meaning between or among and intra meaning inside. Chemical bonds are
considered to be intramolecular forces, for example. These forces are
often stronger than intermolecular forces, which are present between
atoms or molecules that are not bonded.
Magnetism.
Chemical
Polarity is a separation of electric charge leading to a molecule or
its chemical groups having an
Electric Dipole
Moment, with a negatively charged end and a positively charged end.
Polar molecules must contain polar bonds due to a difference in
electronegativity between the bonded atoms. A polar molecule with two or
more polar bonds must have a geometry which is asymmetric in at least one
direction, so that the bond dipoles do not cancel each other. Polar
molecules interact through dipole–dipole intermolecular forces and
hydrogen bonds. Polarity underlies a number of physical properties
including surface tension,
solubility,
and melting and boiling points.
A molecule may be
nonpolar either when there is an equal sharing of electrons
between the two atoms of a diatomic molecule or because of the
symmetrical arrangement of polar bonds in a more complex molecule.
is a measure of the separation of positive and negative electrical
charges within a system, that is, a measure of the system's overall
polarity. The SI units for electric dipole moment are coulomb-meter (C⋅m);
however, a commonly used unit in atomic physics and chemistry is the
debye (D).
Hydrogen Bond is an
electrostatic attraction between two polar groups
that occurs when a
hydrogen (H) atom, covalently bound to a highly
electronegative atom such as
nitrogen (N),
oxygen (O), or fluorine (F),
experiences the
electrostatic field of another highly electronegative atom nearby.
Hydrogen bonds can occur between
molecules (intermolecular) or within
different parts of a single molecule (intramolecular). Depending on the
nature of the donor and acceptor atoms which constitute the bond, their
geometry, and environment, the energy of a hydrogen bond can vary between
1 and 40 kcal/mol. This makes them somewhat stronger than a van der Waals
interaction, and weaker than covalent or ionic bonds. This type of bond
can occur in inorganic molecules such as
water. and in organic molecules
like
DNA and
proteins. Intermolecular hydrogen bonding is responsible for
the high boiling point of water (100 °C) compared to the other group 16
hydrides that have much weaker hydrogen bonds. Intramolecular hydrogen
bonding is partly responsible for the secondary and tertiary structures
of proteins and nucleic acids. It also plays an important role in the
structure of polymers, both synthetic and natural.
Binary Compounds of Hydrogen are binary chemical compounds containing
just hydrogen and one other chemical element. By convention all binary
hydrogen compounds are called hydrides even when the hydrogen atom in it
is not an anion. These hydrogen compounds can be grouped into several
types.
Dynamic Covalent Chemistry is a synthetic strategy employed by
chemists to make complex supramolecular assemblies from discrete
molecular building blocks. DCvC has allowed access to complex assemblies
such as covalent organic frameworks, molecular knots, polymers, and novel
macrocycles. Not to be confused with dynamic combinatorial chemistry,
DCvC concerns only covalent bonding interactions. As such, it only
encompasses a subset of supramolecular chemistries.
Plastics.
Binder material is any material or substance that holds or draws
other materials together to form a cohesive whole mechanically,
chemically, by
adhesion
or
cohesion. In a more narrow sense, binders are liquid or dough-like
substances that harden by a chemical or physical process and bind fibres,
filler powder and other particles added into it. Examples include glue,
adhesive and thickening.
Binder Jetting is
an additive manufacturing process in which a liquid binding agent is
selectively deposited to join powder particles. Layers of material are
then bonded to form an object.
Cement.
Cohesion in chemistry is the action or property of like molecules
sticking together, being mutually attractive. It is an intrinsic property
of a substance that is caused by the shape and
structure of its
molecules, which makes the distribution of orbiting electrons irregular
when molecules get close to one another, creating electrical attraction
that can maintain a microscopic structure such as a water drop. In other
words, cohesion allows for surface tension, creating a "solid-like" state
upon which light-weight or low-density materials can be placed.
Adhesion
is the tendency of dissimilar particles or
surfaces to cling to one another
(cohesion refers to the tendency of similar or identical
particles/surfaces to cling to one another). The forces that cause
adhesion and cohesion can be divided into several types. The
intermolecular forces responsible for the function of various kinds of
stickers and sticky tape fall into the categories of chemical adhesion,
dispersive adhesion, and diffusive adhesion. In addition to the
cumulative magnitudes of these intermolecular forces, there are also
certain emergent mechanical effects.
Band-Aids.
Adhesive
is any non metallic substance applied to one or both surfaces of two
separate items that binds them together and resists their separation. The
use of adhesives offers many advantages over binding techniques such as
sewing, mechanical fastening, thermal bonding, etc. These include the
ability to bind different materials together, to distribute stress more
efficiently across the joint, the cost effectiveness of an easily
mechanized process, an improvement in aesthetic design, and increased
design flexibility. Disadvantages of adhesive use include decreased
stability at high temperatures, relative weakness in bonding large
objects with a small bonding surface area, and greater difficulty in
separating objects during testing. Adhesives are typically organized by
the method of adhesion. These are then organized into reactive and
non-reactive adhesives, which refers to whether the adhesive chemically
reacts in order to harden. Alternatively they can be organized by whether
the raw stock is of natural or synthetic origin, or by their starting
physical phase. Adhesives may be found naturally or produced
synthetically. The earliest human use of adhesive-like substances was
approximately 200,000 years ago, when Neanderthals produced tar from the
dry distillation of birch bark for use in binding stone tools to wooden
handles. The first references to adhesives in literature first appeared
in approximately 2000 BC. The Greeks and Romans made great contributions
to the development of adhesives. In Europe, glue was not widely used
until the period AD 1500–1700. From then until the 1900s increases in
adhesive use and discovery were relatively gradual. Only since the last
century has the development of synthetic adhesives accelerated rapidly,
and innovation in the field continues to the present.
Safer glues for laptops, packaging, furniture.
Cell Adhesion Molecules are a subset of cell surface proteins that
are involved in the binding of cells with other cells or with the
extracellular matrix (ECM), in a process called cell adhesion.
Dissociation is a general process in which molecules (or ionic
compounds such as salts, or complexes) separate or split into smaller
particles such as atoms, ions or radicals, usually in a reversible
manner. For instance, when an acid dissolves in water, a covalent bond
between an electronegative atom and a hydrogen atom is broken by heterolytic fission, which gives a proton (H+) and a negative ion.
Dissociation is the opposite of recombination, which in physics is a
combining of charges or
transfer of electrons in a gas that
results in the neutralization of ions; important for ions arising from
the passage of high-energy particles.
Recombination
in genetics is a combining of genes or characters different from what
they were in the parents.
Heterolysis is the process of cleaving a covalent bond where one
previously bonded species takes both original bonding electrons from the
other species. During heterolytic bond cleavage of a neutral molecule, a
cation and an anion will be generated. Most commonly the more
electronegative atom keeps the pair of electrons becoming anionic while
the more electropositive atom becomes cationic. Heterolytic fission
almost always happens to single bonds, the process usually produces two
fragment species. The energy required to break the bond is called the
heterolytic bond dissociation energy, which is not equivalent to
homolytic bond dissociation energy commonly used to represent the energy
value of a bond.
Chirality
is a geometric property of some molecules and ions. A chiral molecule/ion
is non-superposable on its mirror image. The presence of an asymmetric
carbon center is one of several structural features that induce chirality
in organic and inorganic molecules.
Water in Space -
Cells -
Microbes
-
Organize -
Metallurgy -
Alchemy.
London Dispersion Force are a type of force acting between atoms and
molecules. London forces are exhibited by all atoms and molecules. The
electron distribution around an atom or molecule undergoes fluctuations
in time. These fluctuations create instantaneous electric fields which
are felt by other nearby atoms and molecules, which in turn adjust the
spatial distribution of their own electrons. The net effect is that the
fluctuations in electron positions in one atom induce a corresponding
redistribution of electrons in other atoms, such that the electron
motions become correlated. While the detailed theory requires a
quantum-mechanical explanation (see quantum mechanical theory of
dispersion forces), the effect is frequently described as the formation
of instantaneous dipoles that (when separated by vacuum) attract each
other. The magnitude of the London dispersion force is frequently
described in terms of a single parameter called the Hamaker Constant,
typically symbolized as "A". For atoms that are located closer together
than the wavelength of light, the interaction is essentially
instantaneous and is described in terms of a "non-retarded" Hamaker
Constant. For entities that are farther apart, the finite time required
for the fluctuation at one atom to be felt at a second atom
("retardation") requires use of a "Retarded" Hamaker constant.
Unlocking the secrets of chemical bonding with machine learning.
Researchers have developed a Bayesian learning model of chemisorption, or
Bayeschem for short, aiming to use artificial intelligence to unlock the
nature of chemical bonding at catalyst surfaces. A new machine learning
approach offers important insights into catalysis, a fundamental process
that makes it possible to reduce the emission of toxic exhaust gases or
produce essential materials like fabric. The d-band theory of
chemisorption used in Bayeschem is a theory describing chemical bonding
at solid surfaces involving d-electrons that are usually shaped like a
four-leaf clover. The model explains how d-orbitals of catalyst atoms are
overlapping and attracted to adsorbate valence orbitals that have a
spherical or dumbbell-like shape. It has been considered the standard
model in heterogeneous catalysis since its development by Hammer and
Nørskov in the 1990s, and though it has been successful in explaining
bonding trends of many systems, Xin said the model fails at times due to
the intrinsic complexity of electronic interactions.
Chemisorption is a kind of adsorption which involves a chemical
reaction between the surface and the adsorbate. New chemical bonds are
generated at the adsorbant surface. Examples include macroscopic
phenomena that can be very obvious, like corrosion, and subtler effects
associated with heterogeneous catalysis, where the catalyst and reactants
are in different phases. The strong interaction between the adsorbate and
the substrate surface creates new types of electronic bonds. In contrast
with chemisorption is physisorption, which leaves the chemical species of
the adsorbate and surface intact. It is conventionally accepted that the
energetic threshold separating the binding energy of "physisorption" from
that of "chemisorption" is about 0.5 eV per adsorbed species. Due to
specificity, the nature of chemisorption can greatly differ, depending on
the chemical identity and the surface structural properties. The bond
between the adsorbate and adsorbent in chemisorption is either ionic or
covalent.
Compound - Two Different Elements
Compound is a
molecule that contains at least
two different
elements. Every
combination of atoms is a molecule, but not
all molecules are
compounds. Hydrogen gas (H2) is a
molecule,
but not a compound because it is made of only one element.
Water
(H2O) can be called a molecule or a compound because it is made
of hydrogen (H) and oxygen (O) atoms.
Chemical
Compound is an entity consisting of two or more
atoms, at least two from different
chemical elements, which associate via
chemical bonds. There are four
types of compounds, depending on how the constituent atoms are held
together: molecules held together by covalent bonds, ionic compounds held
together by ionic
bonds, intermetallic compounds held together by
metallic bonds, and certain complexes held together by
coordinate
covalent bonds. Many chemical compounds have a unique numerical
identifier assigned by the Chemical Abstracts Service or CAS
number.
Inorganic Compound is a
chemical compound where there is an absence of carbon in its
composition, and is of a non-biologic origin, and cannot be found or
incorporated into a living organism.
Materials -
Elements.
Organic Compound
is virtually any chemical compound that contains
carbon, although a
consensus definition remains elusive and likely arbitrary. Organic
compounds are rare terrestrially, but of central importance because all
known life is based on organic compounds. The most basic petrochemicals
are considered the building blocks of organic chemistry. There are now more than ten million
Organic Compounds known by chemists.
Binary Compound is a
substance composed of exactly
two different
elements, which are substances that cannot be simplified further
by chemical means. Examples of binary compounds include
H2O, H2S, and NH3. Examples of substances that
are not chemical compounds include Au, Fe, O, HCN, and HNO3.
Diatomic
Molecule.
Binary Phase is chemical compound containing two different elements.
Some binary phases compounds are molecular. More typically binary phase
refers to extended solids.
Composite
is a
conceptual whole
made up of complicated and related parts. Consisting of separate
interconnected parts.
Atoms will
bond together under certain
environmental conditions when they are close enough. And when certain
atoms bind together they can form molecules. And molecules can bind
together with other molecules under certain environmental conditions. But
in order for life to happen, molecules need instructions from the DNA so
they will know how to bond with other molecules and know which molecules
to bond with so they can create complex structures like cells that are
needed to create animal life.
We don't know where atoms came from
or how atoms are made or what atoms are made of. And we are not totally
sure why atoms interact with other atoms. And we are not sure how atoms
create molecules and not just create bigger atoms. We still don't
know why exactly how electricity works, we only know that electricity
exists and we only know how to control electricity to a certain degree.
Carbon
Carbon Atoms make up almost 85% of all known compounds.
Carbon Atoms can make around 1.7 million different
compounds. Carbon can form
four covalent bonds to
create an organic molecule. The simplest carbon
molecule is
methane or CH4.
Carbon-12 is the more abundant carbon of the two stable
isotopes, amounting to 98.93% of the element carbon; its abundance is due
to the triple-alpha process by which it is created in
stars. Carbon-12 is of particular importance
in its use as the standard from which atomic masses of all nuclides are
measured: its mass number is 12 by definition and contains
6 protons,
6
neutrons and
6 electrons. An
oxygen atom is 8-8-8 and
nitrogen is 7-7-7.
Boron
has 5 protons, 5 neutrons and 5 electrons.
Beryllium has 4 protons, 4 neutrons and 4 electrons.
Lithium
has 3 protons, 3 neutrons and 3 electrons.
Helium
has 2 protons, 2 neutrons, and 2 electrons. Heavy Hydrogen or
Deuterium has 1 proton, 1 neutron, and 1 electron. Deuterium is an
isotope of hydrogen. Atomic number of deuterium is 1 and the mass
number is 2. Nearly all deuterium found in nature was produced in the Big
Bang 13.8 billion years ago.
Carbon is a chemical
element with
symbol C and atomic number 6. It is nonmetallic and
tetravalent—making four electrons available to form covalent chemical
bonds. Three isotopes occur naturally, 12C and 13C being stable, while
14C is a radioactive isotope, decaying with a half-life of about 5,730
years. Carbon is one of the few elements known since
antiquity.
Isotopes of
Carbon, Carbon (6C) has 15 known isotopes, from 8C to 22C, of which
12C and 13C are stable.
Isotope
are
variants of a particular chemical element which
differ in neutron
number. All
Isotopes of a given element have the
same number of protons
in each atom. Each of two or more forms of the same element contain
equal numbers of protons but different numbers of neutrons in their
nuclei, and hence differ in relative atomic mass but not in chemical
properties; in particular, a radioactive form of an element.
Carbon-Based
Life is a key component of all known
life on Earth. Complex molecules
are made up of carbon bonded with other elements, especially
oxygen,
hydrogen and
nitrogen, and carbon can bond with all of these because of
its four
valence electrons. Carbon is abundant on Earth. It is also
lightweight and relatively small in size, making it easier for
enzymes to
manipulate carbon molecules. It is assumed in
astrobiology that if life exists somewhere else in the universe, it will
also be carbon-based.
Organic Compound
-
Organic Matter -
Carbon Capture -
Carbon-Fiber -
Graphene
Building
Blocks of Life -
Human Body
Composition
Pentadecane is an
alkane
hydrocarbon with the chemical formula C15H32.
Hydrocarbon is an
organic compound
consisting entirely of
hydrogen and
carbon. Hydrocarbons are
examples of group 14 hydrides. Hydrocarbons from which one hydrogen atom
has been removed are functional groups called hydrocarbyls. Because
carbon has 4
electrons in its outermost shell (and because each
covalent
bond requires a donation of 1 electron, per atom, to the bond) carbon has
exactly four bonds to make, and is only stable if all 4 of these bonds
are used. Aromatic hydrocarbons (arenes), alkanes, cycloalkanes and
alkyne-based compounds are different types of hydrocarbons. Most
Hydrocarbons found on Earth naturally occur in crude oil, where
decomposed organic matter provides an abundance of carbon and hydrogen
which, when bonded, can catenate to form seemingly limitless chains.
HFC's.
Thermodynamics
Thermodynamics is the branch of
physics which deals with the
energy and
work of a
system.
Thermodynamics is the branch of
science concerned with
heat and
temperature and their relation to
energy and work. It states that the behavior of these quantities is
governed by the four laws of thermodynamics (
isobaric,
isochoric,
isothermal and
adiabatic), irrespective of the
composition or specific
properties of the material or system in
question. The laws of thermodynamics are explained in terms of
microscopic constituents by
statistical mechanics. Thermodynamics
applies to a wide variety of topics in science and engineering,
especially physical chemistry, chemical engineering and mechanical
engineering.
Thermoacoustics
(refrigeration) -
Entropy
Laws of Thermodynamics define fundamental physical
quantities (
temperature,
energy, and
entropy) that characterize
thermodynamic systems at thermal
equilibrium. The laws describe how
these quantities behave under various circumstances, and forbid certain
phenomena, such as
perpetual motion.
Second Law of Thermodynamics "what goes up must come down".
Thermal Electric Energy.
Second Law of Thermodynamics dictates that everything
ages,
dies, and
decays, and states that the total
entropy of an
isolated system always increases over
time, or
remains constant in
ideal
cases where the system is in a
steady state or undergoing a reversible
process. The increase in entropy accounts for the
irreversibility of
natural processes, and the
asymmetry between
future and past.
Historically, the second law was an empirical finding that was accepted
as an axiom of thermodynamic theory. Statistical thermodynamics,
classical or
quantum, explains the microscopic origin of the law. The
second law has been expressed in many ways. There is an upper limit to
the
efficiency of conversion of
heat to work
in a heat engine.
New Stars
still being Formed -
The Cycle of
Life
Newton's Third Law
states that
for every action, there is an equal
and opposite reaction. The statement means that in every
interaction, there is a pair of forces acting on the two interacting
objects. The size of the forces on the first object equals the size of
the force on the second object.
Cause and Effect.
Conservation of Mass - Mass can neither be created nor destroyed, only
transferred.
Thermodynamic
Law is a branch of science concerned with
heat and
temperature and their relation to
energy and
work.
Isothermal Process is a change of a system, in which the temperature
remains constant: ΔT = 0. This typically occurs when a system is in
contact with an outside thermal reservoir (heat bath), and the change in
the system will occur slowly enough to allow the system to continue to
adjust to the temperature of the reservoir through heat exchange. In
contrast, an adiabatic process is where a system exchanges no heat with
its surroundings (Q = 0). In other words, in an isothermal process, the
value ΔT = 0 and therefore the change in internal energy ΔU = 0 (only for
an ideal gas) but Q ≠ 0, while in an adiabatic process, ΔT ≠ 0 but Q = 0.
Isochoric Process is a thermodynamic process during which the volume
of the closed system undergoing such a process remains constant. An
isochoric process is exemplified by the heating or the cooling of the
contents of a sealed, inelastic container: The thermodynamic process is
the addition or removal of heat; the isolation of the contents of the
container establishes the closed system; and the inability of the
container to deform imposes the constant-volume condition. The isochoric
process here should be a quasi-static process.
Endothermic
Process is any process which requires or absorbs energy from its
surroundings, usually in the form of heat. It may be a chemical process,
such as dissolving ammonium nitrate in water, or a physical process, such
as the melting of ice cubes.
Explosions -
Combustion
Exothermic Process describes a process or
reaction that
releases energy from the
system to its surroundings, usually in the form of
heat, but also in a
form of light (e.g. a spark,
flame, or flash), electricity (e.g. a
battery), or sound (e.g. explosion heard when burning hydrogen). Its
etymology stems from the Greek prefix έξω (exō, which means "outwards")
and the Greek word θερμικός (thermikόs, which means "thermal"). The term
exothermic was first coined by Marcellin Berthelot. The opposite of an
exothermic process is an endothermic process, one that absorbs energy
usually in the form of heat. The concept is frequently applied in the
physical sciences to chemical reactions where chemical bond energy is
converted to thermal energy (heat). Exothermic (and endothermic)
describe two types of chemical reactions or systems found in nature, as
follows. Simply stated, after an exothermic reaction, more energy has
been released to the surroundings than was absorbed to initiate and
maintain the reaction. An example would be the burning of a candle,
wherein the sum of calories produced by combustion (found by looking at
radiant heating of the surroundings and visible light produced, including
the increase in temperature of the fuel (wax) itself, which oxygen
converts to hot CO2 and water vapor) exceeds the number of calories
absorbed initially in lighting the flame and in the flame maintaining
itself (some energy is reabsorbed and used in melting, then vaporizing
the wax, etc. but is far outstripped by the energy released in converting
the relatively weak double bond of oxygen to the stronger bonds in
CO2 and H2O). On the other hand, in an endothermic reaction or system,
energy is taken from the surroundings in the course of the reaction,
usually driven by a favorable entropy increase in the system. An example
of an endothermic reaction is a first aid cold pack, in which the
reaction of two chemicals, or dissolving of one in another, requires
calories from the surroundings, and the reaction cools the pouch and
surroundings by absorbing heat from them. The production of wood by
photosynthesis is an endothermic process: trees absorb radiant energy
from the sun and use it in endothermic reactions such as taking apart CO2
and H2O and recombining the atoms to produce cellulose and other organic
chemicals, as well as O2. The wood may later be burned in a fireplace,
exothermically releasing the energy of O2 in the form of heat and light
to their surroundings, e.g. to a home's interior.
Adiabatic Process occurs without transfer of heat or mass of
substances between a thermodynamic system and its surroundings. In an
adiabatic process, energy is transferred to the surroundings only as
work. The adiabatic process provides a rigorous conceptual basis for the
theory used to expound the first law of thermodynamics, and as such it is
a key concept in thermodynamics. Some chemical and physical processes
occur so rapidly that they may be conveniently described by the term
"adiabatic approximation", meaning that there is not enough time for the
transfer of energy as heat to take place to or from the system. By way of
example, the
adiabatic flame temperature is an idealization that uses the
"adiabatic approximation" so as to provide an upper limit calculation of
temperatures produced by combustion of a fuel. The adiabatic flame
temperature is the temperature that would be achieved by a flame if the
process of combustion took place in the absence of heat loss to the
surroundings. In meteorology and oceanography, the adiabatic cooling
process produces condensation of moisture or salinity and the parcel
becomes oversaturated. Therefore, it is necessary to take away the
excess. There the process becomes a pseudo-adiabatic process in which the
liquid water/salt that condenses is assumed to be removed as soon as it
is formed, by idealized instantaneous precipitation. The pseudoadiabatic
process is only defined for expansion, since a parcel that is compressed
become warmer and remains undersaturated.
Thermodynamic Equilibrium is an axiomatic concept of thermodynamics.
It is an internal state of a single thermodynamic system, or a relation
between several thermodynamic systems connected by more or less
permeable or impermeable walls. In thermodynamic equilibrium there are
no net macroscopic flows of matter or of energy, either within a system
or between systems. In a system in its own state of internal
thermodynamic
equilibrium, no macroscopic
change occurs. Systems in mutual thermodynamic equilibrium are
simultaneously in mutual thermal, mechanical, chemical, and radiative
equilibria. Systems can be in one kind of mutual equilibrium, though not
in others. In thermodynamic equilibrium, all kinds of equilibrium hold
at once and indefinitely, until disturbed by a thermodynamic operation.
In a macroscopic equilibrium, almost or perfectly exactly balanced
microscopic exchanges occur; this is the physical explanation of the
notion of macroscopic equilibrium. A thermodynamic system in a state of
internal thermodynamic equilibrium has a
spatially
uniform temperature. Its intensive properties, other than
temperature, may be driven to spatial inhomogeneity by an unchanging
long-range force field imposed on it by its surroundings. In systems that
are at a state of non-equilibrium there are, by contrast, net flows of
matter or energy. If such changes can be triggered to occur in a system
in which they are not already occurring, the system is said to be in a
meta-stable equilibrium. Though not a widely named a "law," it is an
axiom of thermodynamics that there exist states of thermodynamic
equilibrium. The second law of thermodynamics states that when a body of
material starts from an equilibrium state, in which, portions of it are
held at different states by more or less permeable or impermeable
partitions, and a thermodynamic operation removes or makes the partitions
more permeable and it is isolated, then it spontaneously reaches its own,
new state of internal thermodynamic equilibrium, and this is accompanied
by an increase in the sum of the entropies of the portions.
Non-Equilibrium Thermodynamics deals with physical systems that are
not in thermodynamic equilibrium but can adequately be described in terms
of variables (non-equilibrium state variables) that represent an
extrapolation of the variables used to specify the system in
thermodynamic equilibrium. Non-equilibrium thermodynamics is concerned
with transport processes and with the rates of chemical reactions. It
relies on what may be thought of as more or less nearness to
thermodynamic equilibrium. Non-equilibrium thermodynamics is a work in
progress, not an established edifice. This article will try to sketch
some approaches to it and some concepts important for it. Almost all
systems found in
nature are not in thermodynamic
equilibrium; for they are changing or can be triggered to change over
time, and are continuously and discontinuously subject to flux of
matter and
energy
to and from other systems and to chemical reactions. Some systems and
processes are, however, in a useful sense, near enough to thermodynamic
equilibrium to allow description with useful accuracy by currently known
non-equilibrium thermodynamics. Nevertheless, many natural systems and
processes will always remain far beyond the scope of non-equilibrium
thermodynamic methods. This is because of the very small size of atoms,
as compared with macroscopic systems.
Thermodynamic System is the material and radiative content of a
macroscopic volume in space, that can be adequately described by
thermodynamic state variables such as temperature, entropy, internal
energy and pressure.
Chemical Thermodynamics is the study of the interrelation of
heat and work with chemical reactions or with physical changes of state
within the confines of the laws of thermodynamics.
Thermal Decomposition is a chemical decomposition caused by
heat. The decomposition
temperature of a substance is the temperature at which the substance
chemically decomposes. The reaction is usually endothermic as heat is
required to break chemical bonds in the compound undergoing
decomposition. If decomposition is sufficiently exothermic, a positive
feedback loop is created producing thermal runaway and possibly an explosion.
Thermal
Expansion is the tendency of matter to change its shape, area, and
volume in response to a change in temperature. Temperature is a
Monotonic Function of the average molecular kinetic energy of a
substance. When a substance is heated, the kinetic energy of its
molecules increases. Thus, the molecules begin vibrating/moving more and
usually maintain a greater average separation. Materials which contract
with increasing temperature are unusual; this effect is limited in size,
and only occurs within limited temperature ranges (see examples below).
The relative expansion (also called strain) divided by the change in
temperature is called the material's coefficient of thermal expansion and
generally varies with temperature.
Hot Air.
Helmholtz Free Energy is a
Thermodynamic Potential that measures the useful work obtainable from
a closed thermodynamic system at a constant temperature and volume. The
negative of the change in the Helmholtz energy during a process is equal
to the maximum amount of work that the system can perform in a
thermodynamic process in which volume is held constant. If the volume
were not held constant, part of this work would be performed as boundary
work. This makes the Helmholtz energy useful for systems held at constant
volume. Furthermore, at constant temperature, the Helmholtz energy is
minimized at equilibrium.
Internal Energy of a system is the
energy contained within the
system, excluding the
kinetic energy of
motion of the system as a whole and the
potential energy
of the system as a whole due to external force fields. It keeps account
of the gains and losses of energy of the system that are due to
changes in its internal state. The internal energy of a system can be
changed by transfers of matter or heat or by doing work. When matter
transfer is prevented by impermeable containing walls, the system is said
to be closed. Then the first law of thermodynamics states that the
increase in internal energy is equal to the total
heat added plus the work
done on the system by its surroundings. If the containing walls pass
neither matter nor energy, the system is said to be isolated and its
internal energy cannot change. The first law of thermodynamics may be
regarded as establishing the existence of the internal energy. The
internal energy is one of the two cardinal state functions of the state
variables of a thermodynamic system.
Enthalpy
is a property of a thermodynamic system. The enthalpy of a system is
equal to the system's internal energy plus the product of its pressure
and volume. For processes at constant pressure, the heat absorbed or
released equals the change in enthalpy. The unit of measurement for
enthalpy in the International System of Units (SI) is the joule. Other
historical conventional units still in use include the British thermal
unit (BTU) and the calorie. Enthalpy comprises a system's internal
energy, which is the energy required to create the system, plus the
amount of work required to make room for it by displacing its environment
and establishing its volume and pressure. Enthalpy is defined as a state
function that depends only on the prevailing equilibrium state identified
by the system's internal energy, pressure, and volume. It is an extensive
quantity. Enthalpy is the preferred expression of system energy
changes in many chemical, biological, and physical measurements at
constant pressure, because it simplifies the description of energy
transfer. At constant pressure, the enthalpy change equals the energy
transferred from the environment through heating or work other than
expansion work. The total enthalpy,
H, of
a system cannot be measured directly. The same situation exists in
classical mechanics: only a change or difference in energy carries
physical meaning. Enthalpy itself is a thermodynamic potential, so in
order to measure the enthalpy of a system, we must refer to a defined
reference point; therefore what we measure is the change in enthalpy, ΔH.
The ΔH is a positive change in endothermic reactions, and negative in
heat-releasing exothermic processes.
Engineering Thermodynamics
(Book - Wiki)
Thermoplastic
Urea is
an organic compound with the chemical formula CO(NH2)2. Urea serves an
important role in the metabolism of nitrogen-containing compounds by
animals, and is the main nitrogen-containing substance in the urine of
mammals.
Thermodynamics of Computation (pdf)
Chemical Process Modeling is a computer modeling technique
used in chemical engineering process design. It typically involves using
purpose-built software to define a system of interconnected components,
which are then solved so that the steady-state or dynamic behavior of
the system can be predicted. The system components and connections are
represented as a Process Flow diagram. Simulations can be as simple as
the mixing of two substances in a tank, or as complex as an entire
alumina refinery.
Triple Point of a substance is the temperature and pressure
at which the three phases (gas, liquid, and solid) of that substance
coexist in thermodynamic equilibrium.
Compound
Chem.
Thermal
Energy (geothermal) -
Thermal Electric Energy
-
Solar Thermal Energy
(sun energy)
Thermal Energy is the total
energy an object has due to the internal
motions of its particles. The
temperature is related to the average
kinetic energy—not the total
kinetic energy. Put a piece of cold pizza on top of a sheet of aluminum
foil and then stick it in the oven to heat up. After about 10 minutes,
the pizza should be nice and hot—the aluminum foil is the approximately
the same temperature. You can pull the aluminum foil out with your
fingers, but not the pizza. Although the aluminum foil has a high
temperature, its low mass means it doesn't have much thermal energy.
Without a lot of thermal energy in the foil, your fingers won't get
burned. Meaning? Thermal energy and temperature are different things.
Thermal
Conductivity of a material is a measure of its
ability to conduct heat.
Heat transfer occurs at a lower rate in materials of low thermal
conductivity than in materials of high thermal conductivity. For
instance, metals typically have high thermal conductivity and are very
efficient at conducting heat, while the opposite is true for
insulating materials
like Styrofoam. Correspondingly, materials of high thermal conductivity
are widely used in
heat
sink applications and materials of low thermal conductivity are used
as thermal insulation. The reciprocal of thermal conductivity is called
thermal resistivity.
Superconductivity.
Thermal is a column of rising
air in the lower
altitudes of
Earth's atmosphere.
Thermals are created by the uneven heating of Earth's surface from
solar radiation, and are an example of
convection, specifically
atmospheric convection. The Sun warms the ground, which in turn
warms the air directly above it. Dark earth, urban areas, and roadways
are good sources of thermals.
Temperature - Cold - Hot
Temperature is an
objective comparative measurement of
Hot or
Cold. It is measured by a
thermometer. Several scales and units exist for measuring temperature,
the most common being Celsius (denoted °C; formerly called centigrade),
Fahrenheit (denoted °F), and, especially in science, Kelvin (denoted K).
The coldest theoretical temperature is absolute zero, at which the
thermal motion of atoms and molecules reaches its minimum – classically,
this would be a state of motionlessness, but quantum uncertainty dictates
that the particles still possess a finite
zero-point energy. Absolute
zero is denoted as 0 K on the Kelvin scale, −273.15 °C on the Celsius
scale, and −459.67 °F on the Fahrenheit scale. The kinetic theory offers
a valuable but limited account of the behavior of the materials of
macroscopic bodies, especially of fluids. It indicates the absolute
temperature as proportional to the average
kinetic energy of the random
microscopic motions of those of their constituent microscopic particles,
such as electrons, atoms, and molecules, that move freely within the
material. Thermal vibration of a segment of protein alpha helix: The
amplitude of the vibrations increases with temperature. Temperature is
important in all fields of natural science including physics, geology,
chemistry, atmospheric sciences, medicine and biology as well as most
aspects of daily life.
Thermometer is a
device that
measures temperature or a temperature
gradient. A thermometer has two important elements: (1) a temperature
sensor (e.g. the bulb of a mercury-in-glass thermometer or the pyrometric
sensor in an infrared thermometer) in which some change occurs with a
change in temperature; and (2) some means of converting this change into
a numerical value (e.g. the visible scale that is marked on a
mercury-in-glass thermometer or the digital readout on an infrared
model). Thermometers are widely used in technology and industry to
monitor processes, in meteorology, in medicine, and in scientific
research. Some of the principles of the thermometer were known to Greek
philosophers of two thousand years ago. The modern thermometer gradually
evolved from the thermoscope with the addition of a scale in the early
17th century and standardisation through the 17th and 18th centuries.
Infrared Thermometers.
Bimetallic Strip is used to convert a temperature change into
mechanical displacement. The strip consists of two strips of different
metals which expand at different rates as they are heated, usually steel
and copper, or in some cases steel and brass. The different expansions
force the flat strip to bend one way if heated, and in the opposite
direction if cooled below its initial temperature. The metal with the
higher coefficient of thermal expansion is on the outer side of the curve
when the strip is heated and on the inner side when cooled. Bimetallic
strip is a temperature-sensitive electrical contact used in some
thermostats, consisting of two bands of different metals joined face
to face along their lengths. When heated, the metals expand at different
rates, causing the strip to bend. Electrical-resistance thermometers
characteristically use platinum and, like thermistors, operate on the
principle that electrical resistance varies with changes in temperature.
However, they can measure a much greater temperature range than
thermistors.
Thermocouples are among the most widely used industrial thermometers.
They are composed of two wires made of different materials joined
together at one end and connected to a voltage-measuring device at the
other. A temperature difference between the two ends creates a voltage
that can be measured and translated into a measure of the temperature of
the junction end. The bimetallic strip constitutes one of the most
trouble-free and durable thermometers. It is simply two strips of
different metals bonded together and held at one end. When heated, the
two strips expand at different rates, resulting in a bending effect that
is used to measure the temperature change. Thermostats formerly used
bimetallic strips as temperature sensors, but modern digital thermostats
use
thermistors, which is a type of resistor whose resistance is strongly
dependent on temperature, more so than in standard resistors.
Temperature Measurement or thermometry, describes the process of
measuring a current local temperature for immediate or later evaluation.
Datasets consisting of repeated standardized measurements can be used to
assess temperature trends.
Thermopile is an
electronic device that
converts thermal
energy into electrical energy. It is composed of several thermocouples
connected usually in series or, less commonly, in parallel. Such a device
works on the principle of the thermoelectric effect, i.e., generating a
voltage when its dissimilar metals (thermocouples) are exposed to a
temperature difference.
Temperature Gradient is a physical quantity that describes in which
direction and at what rate the temperature changes the most rapidly
around a particular location. The temperature gradient is a dimensional
quantity expressed in units of degrees (on a particular temperature
scale) per unit length. The SI unit is kelvin per second (K/s). It can be
found in the formula for dQ/dt, the rate of heat transfer per second.
Temperature gradients in the atmosphere are important in the atmospheric
sciences (
meteorology, climatology and
related fields). T.g is defined as
ratio of
the difference between temperature of 2 thermometer to distance between
them.
Degree in Temperature is used in several scales of temperature. The
symbol ° is usually used, followed by the initial letter of the unit, for
example “°C” for degree(s) Celsius. A degree can be defined as a set
change in temperature measured against a given scale, for example, one
degree Celsius is one hundredth of the temperature change between the
point at which water starts to change state from solid to liquid state
and the point at which it starts to change from its gaseous state to
liquid.
Room Temperature is the range of air temperatures that people prefer
for indoor settings, which
feel
comfortable when wearing typical indoor clothing. As a medical
definition, the range generally considered to be suitable for human
occupancy is between 15 degrees Celsius (59 degrees Fahrenheit) and 25 °C
(77 °F), though
human comfort
can extend somewhat beyond this range depending on factors such as
humidity and air circulation. In certain fields, like science and
engineering, and within a particular context, "room temperature" can have
varying agreed upon values for temperature.
Celsius
scale, the zero value is at the
freezing
point of water and the 100 value is at the
Boiling Point,
which depends on atmospheric conditions.
Fahrenheit, water
freezes into ice is defined as 32 °F, and the
boiling point of water is
defined to be 212 °F, a 180 °F separation, as defined at
sea level and
standard atmospheric pressure.
Humidity -
Dew Point.
Celsius to Fahrenheit is (C times 2
plus 30 = F) Cx2+30=F
Fahrenheit to Celsius is (F minus 30
divided by 2 = C) F-30/2=C
Note:
conversion numbers
will not be exact, it's just to get you close to an estimate.
(0C = 32F, 27C = 80F, for every 10 Degrees F increase is equal to around a 5C increase).
Cold is the presence of
low temperature, especially in the
atmosphere. In common usage, cold is
often a subjective perception. A lower bound to temperature is absolute
zero, defined as 0.00 K on the Kelvin scale, an absolute thermodynamic
temperature scale. This corresponds to −273.15 °C on the Celsius scale,
−459.67 °F on the Fahrenheit scale, and 0.00 °R on the Rankine scale.
Since temperature relates to the
thermal energy held by an object or a
sample of matter, which is the
kinetic energy of the random
motion of the
particle constituents of matter, an object will have less thermal energy
when it is colder and more when it is hotter. If it were possible to cool
a system to absolute zero, all motion of the particles in a sample of
matter would cease and they would be at complete rest in this classical
sense. The object would be described as having zero thermal energy.
Microscopically in the description of quantum mechanics, however, matter
still has zero-point energy even at absolute zero, because of the
uncertainty principle.
Ice (water) -
Ice Therapy.
Cryogenics is the production and behaviour of materials at very low
temperatures. A person who studies elements that have been subjected to
extremely cold temperatures is called a cryogenicist. It is not
well-defined at what point on the temperature scale refrigeration ends
and cryogenics begins, but scientists assume a gas to be cryogenic if it
can be liquefied at or below −150 °C (123 K; −238 °F). The U.S. National
Institute of Standards and Technology has chosen to consider the field of
cryogenics as that involving temperatures below −180 °C (93 K; −292 °F).
This is a logical dividing line, since the normal boiling points of the
so-called permanent gases (such as helium, hydrogen, neon, nitrogen,
oxygen, and normal air) lie below −180 °C while the Freon refrigerants,
hydrocarbons, and other common
refrigerants have
boiling points above
−180 °C. Discovery of superconducting materials with critical
temperatures significantly above the boiling point of liquid nitrogen has
provided new interest in reliable, low cost methods of producing high
temperature cryogenic refrigeration. The term "high temperature
cryogenic" describes temperatures ranging from above the boiling point of
liquid nitrogen, −195.79 °C (77.36 K; −320.42 °F), up to −50 °C (223 K;
−58 °F), the generally defined upper limit of study referred to as
cryogenics.
Liquid Nitrogen
is
nitrogen in a
liquid state at an extremely low
temperature. It is a colorless clear liquid with a density of 0.807 g/ml
at its boiling point (−195.79 °C (77 K; −320 °F)) and a dielectric
constant of 1.43.
Absolute Zero
is the lower limit of the thermodynamic temperature scale, a state at
which the enthalpy and entropy of a cooled ideal gas reaches its minimum
value, taken as 0. The theoretical temperature is determined by
extrapolating the ideal gas law; by international agreement, absolute
zero is taken as −273.15° on the Celsius scale (International System of
Units), which
equates to −459.67° on the Fahrenheit scale (United States
customary units or Imperial units). The corresponding Kelvin and Rankine
temperature scales set their zero points at absolute zero by definition.
Ice.
Kelvin
is a unit of measure for temperature based upon an absolute scale. It is
one of the seven base units in the International System of Units (SI) and
is assigned the unit symbol K. The Kelvin scale is an absolute,
thermodynamic temperature scale using as its null point absolute zero,
the temperature at which all thermal motion ceases in the classical
description of thermodynamics.
Quantum Super Computer is cooled to 0.01 Kelvin, which is the coldest
place in the known universe, 100 times colder the space, which is 2.7
kelvins (K) (−270.45 °C; −454.81 °F).
Planck
Temperature denoted by TP, is the unit of temperature in the system
of natural units known as
Planck units. It serves as the defining unit of the
Planck temperature scale. In this scale the magnitude of the Planck
temperature is equal to 1, while that of absolute zero is 0. Other
temperatures can be converted to Planck temperature units. For example, 0
°C = 273.15 K = 1.9279 × 10−30TP. In SI units, the Planck temperature is
about 1.417×1032 kelvin (equivalently, degrees Celsius, since the
difference is trivially small at this scale), or 2.55×1032 degrees
Fahrenheit or Rankine.
Planck units are a set of units of measurement defined exclusively in
terms of five universal physical constants, in such a manner that these
five physical constants take on the numerical value of 1 when expressed
in terms of these units.
Body Temperature
-
Dark Matter
Negative Temperature is temperature that can be expressed as a
negative quantity on the Kelvin or Rankine scales. This should be
distinguished from temperatures expressed as negative numbers on
non-thermodynamic Celsius or Fahrenheit scales, which are nevertheless
higher than absolute zero. The absolute temperature (Kelvin) scale can be
understood loosely as a measure of average kinetic energy. Usually,
system temperatures are positive. However, in particular isolated
systems, the temperature defined in terms of Boltzmann's entropy can
become negative.
Spectroscopic Thermometer for Nanomaterials. A scientific team has
found a new way to take the local temperature of a material from an area
about a billionth of a meter wide, or approximately 100,000 times thinner
than a human hair. This discovery promises to improve the understanding
of useful yet unusual physical and chemical behaviors that arise in
materials and structures at the
nano-scale.
Entropy - Running Out of Useful Energy
Entropy is a
thermodynamic quantity representing the
amount of
energy in a
system that is no longer available for
doing mechanical
work.
Entropy (pdf).
High Entropy would indicate
less energy
available for useful work in a system.
Created nor Destroyed -
Transitions -
Conversions -
Variables
-
Invariant -
Alchemy
Low Entropy would
suggest
greater energy. Entropy increases as matter and energy
in the universe degrade to an ultimate state of
inert uniformity.
Decay Half-Life -
Cell Death -
Depreciation -
Chaos -
Disorder -
Dormancy -
Decompose -
Hibernation
Negentropy is
reverse entropy. It
means things becoming
more in
order. By 'order' is meant organization, structure and function. It
is the opposite of randomness or
chaos. One example of
negentropy is a star system such as the
Solar System. Another example is life.
Arrow of Time.
Things Must Change in Life. If things
didn't
change, there would be no life. Our job as humans is to understand
these
changes and react to them accordingly. If things never cooled down,
life could never exist. If things did not
decay, then new things could not be born.
Entropy is on a much slower time scale of change. A
cycle of order to
disorder then back to order then to disorder again and so on and so on.
Things combine and then things fall apart or decay, and then they combine
again and then fall apart again, and so on and so on. And when a
galaxy stops making new stars, then
that galaxy will eventfully fall into disorder until another galaxy can
use its matter to create new stars and make new planets. And when the
universe stops making new galaxies, which has not happened yet, then who
knows what will happen next after that. Most likely some form of
reconfiguration, which would be in trillions and trillions of years from
now. So we have lots of time to think about it. But we have less time to
think about our immediate threats. So its kind of stupid to think about
things that will happen in trillions of years from now if we can't even
live another thousand years.
Death
-
Cycle of Life -
Carbon Dating
-
Calculus Ephemeral is something lasting for a very
short time.
Heat.
Irreversible Process is a process that is not reversible. In
thermodynamics, a change in the thermodynamic state of a system and all
of its surroundings cannot be precisely restored to its initial state by
infinitesimal changes in some property of the system without expenditure
of energy. A system that undergoes an irreversible process may still be
capable of returning to its initial state. However, the impossibility
occurs in restoring the environment to its own initial conditions. An
irreversible process increases the entropy of the universe. Because
entropy is a state function, the change in entropy of the system is the
same, whether the process is reversible or irreversible. The second law
of thermodynamics can be used to determine whether a process is
reversible or not. Some things look the same whether they're moving
forward or moving backwards in reverse.
Entropy in statistical thermodynamics, entropy (usual symbol
S) is a measure of the number of microscopic configurations Ω that
correspond to a thermodynamic system in a state specified by certain
macroscopic
variables. Specifically, assuming that each of the
microscopic configurations is equally probable, the entropy of the
system is the natural logarithm of that number of
configurations,
multiplied by the Boltzmann constant kB (which provides consistency with
the original thermodynamic concept of entropy discussed below, and gives
entropy the dimension of energy divided by temperature).
Entropy and Life (pdf) -
Entropy and Life (wiki)
Thermodynamic free energy is the amount of
work that a thermodynamic
system can perform.
Entropy in order disorder is associated with the
amount of order, disorder, or
chaos in a thermodynamic system.
Entropy
is the number of ways we can rearrange the constituents of a system so
that you don't notice. A low entropy configuration is one in which
there's only a few arrangements that look that way. A high entropy
arrangement is one that there are many arrangements that look that way.
The second law of thermodynamics -- the law that
says that entropy increases in the universe, or in some isolated bit of
the universe. The reason why entropy increases is simply because there
are many more ways to be high entropy than to be low entropy. Boltzmann
explained that if you start with low entropy, it's very natural for it to
increase because there's more ways to be high entropy. What he didn't
explain was why the entropy was ever low in the first place.
Entropy
in information theory systems are modeled by a transmitter,
channel, and receiver. The transmitter produces messages that are sent
through the channel. The channel modifies the message in some way. The
receiver attempts to infer which message was sent.
-
PDF.
Entropic Force
is a
force resulting from the entire system's
thermodynamical tendency to increase its entropy, rather than from a
particular underlying microscopic force. For instance, the internal
energy of an ideal gas depends only on its temperature, and not on the
volume of its containing box, so it is not an energy effect that tends to
increase the volume of the box as gas pressure does. This implies that
the
pressure of an ideal gas has an entropic origin. What is the origin
of such an entropic force? The most general answer is that the effect of
thermal fluctuations tends to bring a
thermodynamic system toward a
macroscopic state that corresponds to a maximum in the number of
microscopic states (or micro-states) that are compatible with this
macroscopic state. In other words, thermal fluctuations tend to bring a
system toward its macroscopic state of maximum entropy.
Enthalpy
is a measurement of
energy in a
thermodynamic system.
Heat Death of the Universe is a plausible ultimate fate of the
universe in which the universe has evolved to a state of no thermodynamic
free energy and therefore can no longer sustain processes that increase
entropy.
Heat death does
not imply any particular absolute temperature; it only requires that
temperature differences or other processes may no longer be exploited to
perform work. In the language of physics, this is when the universe
reaches thermodynamic equilibrium (maximum entropy). If the topology of
the universe is open or flat, or if dark energy is a positive
cosmological constant (both of which are consistent with current data),
the universe will continue expanding forever, and a heat death is
expected to occur, with the universe cooling to approach equilibrium at a
very low
temperature after a very long time
period.
Hypothermia.
Thermal Decomposition is a chemical decomposition caused by heat. The
decomposition temperature of a substance is the temperature at which the
substance chemically decomposes. The reaction is usually endothermic as
heat is required to break chemical bonds in the compound undergoing
decomposition. If decomposition is sufficiently exothermic, a positive
feedback loop is created producing thermal runaway and possibly an
explosion.
Biology (entropy) -
Aging
Landauer's Principle is a physical principle pertaining to the lower
theoretical limit of energy consumption of computation. It holds that
"any logically irreversible manipulation of information, such as the
erasure of a bit or the merging of two computation paths, must be
accompanied by a corresponding entropy increase in
non-information-bearing degrees of freedom of the information-processing
apparatus or its environment. Another way of phrasing Landauer's
principle is that if an observer loses information about a physical
system, the observer loses the ability to extract work from that system.
A so-called logically-reversible computation, in which no information is
erased, may in principle be carried out without releasing any heat. This
has led to considerable interest in the study of reversible computing.
Indeed, without reversible computing, increases in the number of
computations-per-joule-of-energy-dissipated must come to a halt by about
2050: because the limit implied by Landauer's principle will be reached
by then, according to Koomey's law. At 20 °C (room temperature, or 293.15
K), the Landauer limit represents an energy of approximately 0.0172 eV,
or 2.75 zJ. Theoretically, room‑temperature computer memory operating at
the Landauer limit could be changed at a rate of one billion bits per
second with energy being converted to heat in the memory media at the
rate of only 2.85 trillionths of a watt (that is, at a rate of only 2.85
pJ/s). Modern computers use millions of times as much energy per second.
Knowledge Preservation.
Limits of Computation states that there are several physical and
practical limits to the amount of computation or data storage that can be
performed with a given amount of mass, volume, or energy.
Bekenstein Bound is an upper limit on the entropy S, or information
I, that can be contained within a given finite region of space which has
a finite amount of energy—or conversely, the maximal amount of
information required to perfectly describe a given physical system down
to the quantum level. It implies that the information of a physical
system, or the information necessary to perfectly describe that system,
must be finite if the region of space and the energy is finite. In
computer science, this implies that there is a maximal
information-processing rate (Bremermann's limit) for a physical system
that has a finite size and energy, and that a Turing machine with finite
physical dimensions and unbounded memory is not physically possible.
Sun shines for billions of years and the
earths core
stays hot for billions of years. Humans are born with all the energy
producing capabilities they need. But humans were not born with all the knowledge they need that
would explain to us how to utilize energy effectively and
efficiently. This is why
education needs to improve. If we don't start educating people on how
to accurately understand themselves and the world around them, then
people will continue to make bad choices and be forced to make bad
decisions, all because they don't have the necessary knowledge and
information that would allow them to see life more clearly. Every human
has the potential to be intelligent, but we can not utilize this
potential if we never
learn how. Human
education is our endless supply of energy. And we will never be able to
fully utilize our suns and our planets constant flow of energy if we
don't improve education. Everything will be wasted and it will be a
wasted opportunity.
Our window of
opportunity is upon us, and this window will not stay open for long.
Conservation of Mass.
Does Progress slow down Entropy?
Functional Information provides a measure
of complexity by quantifying the probability that an arbitrary
configuration of a system of numerous interacting agents will achieve a
specified degree of function, even with a large number of different
configurations or combinations, the system could evolve, or go extinct,
because functionality does not necessarily mean resilient. And reducing
the number of configurations or combinations could make a system weaker
or unable to adapt.
Emergence of Biocomplexity.
Entropy is one of the few quantities in the physical sciences that
require a particular
direction for time,
sometimes called an
arrow of time.
Chemistry Tools - Chemistry Equipment
Laboratory Equipment Names (image) -
Chemistry Lab Tools Image (photo)
Chemistry
Sets -
Chemistry Kits -
Chemistry Set History (wiki)
-
Science Tools -
Engineering
Tools Mortar is a bowl-shaped
vessel in which substances can be ground and mixed with a pestle.
Pestle is a club-shaped hand tool for
grinding, mashing, pulverizing and mixing substances in a mortar.
Do It
Yourself Science (DIY Medicine) -
DIY Biology
(ethics) -
Procedures
Centrifuge is a piece of equipment that puts an object in rotation
around a fixed axis (spins it in a circle), applying a potentially strong
force perpendicular to the axis of spin (outward). The centrifuge works
using the sedimentation principle, where the
centripetal acceleration
causes denser substances and particles to move outward in the radial
direction. At the same time, objects that are less dense are displaced
and move to the center. In a laboratory centrifuge that uses sample
tubes, the radial acceleration causes denser particles to settle to the
bottom of the tube, while low-density substances rise to the top. There
are 3 types of centrifuge designed for different applications. Industrial
scale centrifuges are commonly used in manufacturing and waste processing
to sediment suspended solids, or to
separate immiscible liquids. An
example is the cream
separator found in dairies. Very high speed
centrifuges and ultracentrifuges able to provide very high accelerations
can
separate fine particles down to the
nano-scale, and
molecules of
different masses. Large centrifuges are used to simulate high gravity or
acceleration environments (for example, high-G training for test pilots).
Medium-sized centrifuges are used in washing machines and at some
swimming pools to wring water out of fabrics. Gas centrifuges are used
for isotope separation, such as to enrich nuclear fuel for fissile isotopes.
Stanford
Bioengineers Develop a 20-cent, Hand-Powered Centrifuge "Hand-powered
ultralow-cost paper centrifuge, or paperfuge." With rotational speeds of
up to 125,000 revolutions per minute, the device separates blood plasma
from red cells in 1.5 minutes, no electricity required. A centrifuge is
critical for detecting diseases such as malaria, African sleeping
sickness, HIV and tuberculosis. This low-cost version will enable precise
diagnosis and treatment in the poor, off-the-grid regions where these
diseases are most prevalent.
Stanford.
Analytical Services Laboratories are
staffed by trained
chemists, material scientists, technicians and
laboratory management with years of industry knowledge and expertise.
Analytical laboratory testing: identify the chemical makeup or
characteristics of a particular sample.
Analytical Chemistry.
Examinations -
Lab Tests (physical health) -
Sensors
Laboratory Analyses is a range of
analytical parameters to provide the necessary evidence for environmental
regulatory compliance and comparative data that can be used to discover
ways to minimize environmental impact.
Hollow-core fiber raises prospects for next-generation scientific
instruments. Hollow-core
optical fibres
combine the free-space propagation performance of the most advanced
interferometers with the length scales of modern optical fibres by
guiding light around bends in an air or vacuum filled core.
Nanodots
- Magnetic Constructors -
Video
Chem 4 Kids -
Molecular Flipbook -
Engineering
Toxicology -
Pharmaceutical Industry
Pyrolysis is a thermochemical
decomposition of organic
material at elevated temperatures in the absence of oxygen (or any
halogen). It involves the simultaneous change of chemical composition and
physical phase, and is irreversible.
Bioanalysis is a sub-discipline of analytical chemistry
covering the quantitative measurement of xenobiotics (drugs and their
metabolites, and biological molecules in unnatural locations or
concentrations) and biotics (macromolecules, proteins, DNA, large
molecule drugs, metabolites) in biological systems.
Janet Iwasa: How 3D Animations help Scientists Visualize what we
can't See (video)
Pub Chem
provides information on the biological activities of small molecules.
Biological properties component database with a fast chemical
structure similarity search tool.
Typical Contents found in Chemistry Sets
Equipment might include:
vials of
dry
chemicals,
metal
wires,
such as
copper,
nickel or zinc, metal filings such as
iron,
graphite rods, a
balance and weights, a
measuring cylinder,
a
thermometer, a
magnifying glass,
pipettes,
beakers,
retorts,
flasks,
test
tubes, U-tubes or other reaction vessels,
cork
stoppers,
watch glasses,
glass and
rubber
tubing,
test tube holders,
retort stands and
clamps,
an
alcohol burner or other heat source,
a
filter funnel and
filter paper,
universal indicator paper or
litmus paper,
safety goggles,
an
instruction manual.
Eppendorf
Tubes are single-use tubes made from polypropylene for
preparing, mixing, centrifuging, transporting and storing solid and
liquid samples and reagents. The product can be used for training,
routine and research laboratories in the areas of life sciences, industry
or chemistry.
Chemicals
might include:
Aluminium ammonium sulfate,
Aluminium sulfate,
Ammonium chloride,
Borax,
Calcium chloride,
Calcium hydroxide,
Calcium oxide,
Calcium oxychloride,
Calcium sulfate,
Cobalt chloride,
Cupric chloride,
Copper sulfate,
Ferric ammonium sulfate,
Ferrous sulfate,
Gum arabic,
Magnesium ribbon,
Magnesium chloride
Magnesium sulfate,
Manganese sulfate,
Phenolphthalein,
Potassium chloride,
Potassium iodide,
Potassium permanganate,
Potassium sulfate
Powdered
charcoal,
Powdered
iron,
Sodium bisulfate,
Sodium bisulfite,
Sodium carbonate,
Sodium ferrocyanide,
Sodium silicate,
Sodium thiosulfate,
Strontium chloride,
Sulfur,
Tannic acid,
Tartaric acid,
Zinc sulfate..
The experiments described in the instruction manual typically require a
number of chemicals not shipped with the chemistry set, because they are common
household chemicals:
Acetic acid (in
vinegar),
Ammonium carbonate ("baker's ammonia" or "salts of hartshorn"),
Citric acid (in
lemons),
Ethanol
(in
denatured alcohol),
Sodium bicarbonate, (
baking
soda),
Sodium chloride ("table salt")
Other chemicals, including strong acids, bases and oxidizers cannot be safely
shipped with the set and others having a limited shelf life have to be purchased
separately from a
drug store:
Hydrochloric acid,
Hydrogen peroxide,
Silver nitrate,,
Sodium hydroxide.
List of Commonly Available Chemicals (wiki)
Amateur Chemistry is the pursuit of chemistry as a
private hobby. Amateur chemistry is
usually done with whatever chemicals are available at disposal at the
privacy of one's home. It should not be confused with clandestine
chemistry, which involves the illicit production of controlled drugs. Notable amateur chemists include Oliver Sacks and Sir Edward Elgar.
Chemistry Resources
American Chemical Society -
American Chemical Society (youtube channel)
The American Oil
Chemists’ Society -
American Chemistry
Journals &
Publications
Industrial & Engineering Chemistry Research
Chemical
Heritage Foundation
Royal Society of
Chemistry -
Royal Society
(wiki)
Related Subject Pages -
Biology -
Cells -
Plants -
Animals -
Insects -
Land -
Environment -
Science
-
Vitamins.
Alchemy - Converting Matter
Alchemy is
change of one
substance into another. Transmutation of metals aimed to purify,
mature, and perfect certain objects.
Transmutation is the action of
changing or the state of
being
changed into another form. It is the changing of one element into
another by radioactive decay, nuclear bombardment, or similar processes.
It is the
conversion
or
transformation of one species into another.
Nuclear
Transmutation is the conversion of one
chemical
element or an isotope into another chemical element. Because any
element or
isotope of one is defined by its number of
protons and
neutrons in its
atoms, i.e. in the atomic nucleus,
nuclear transmutation occurs in any
process where the number of protons or neutrons in the nucleus is
changed.
States of Matter -
Entropy -
Created nor Destroyed
Metamorphism is the change of minerals or geologic texture.
Transition Metal is an
element whose atom has
a partially filled
d sub-shell, or
which can give rise to cations with an incomplete d sub-shell, or any
element in the d-block of the periodic table, which includes groups 3 to
12 on the
periodic table. The elements in the
periodic table are often divided into four categories: (1) main group
elements, (2) transition metals, (3) lanthanides, and (4) actinides. The
main group elements include the active metals in the two columns on the
extreme left of the periodic table and the
metals, semimetals, and
nonmetals in the six columns on the far right. The transition metals are
the metallic elements that
serve as a bridge,
or
transition,
between the two sides of the table. The lanthanides and the actinides at
the bottom of the table are sometimes known as the inner transition
metals because they have atomic numbers that fall between the first and
second elements in the last two rows of the transition metals.
Conversions.
Localization of d-electrons in transition metals determined.
Transition metals have many applications in engineering, electrochemistry
and catalysis. To understand their properties, the interplay between
atomic localization and delocalization of the outer electrons in the d
orbitals is crucial. This insight is now provided by a special end
station at
BESSY II
with highest precision, as demonstrated by a study of copper, nickel and
cobalt with interesting quantitative results.
Transition
metals and non-ferrous metals such as copper, nickel and cobalt are not
only suitable as materials in engineering and technology, but also for a
wide range of applications in electrochemistry and catalysis. Their
chemical and physical properties are related to the occupation of the
outer
d-orbital
shells around the atomic nuclei. The energetic levels of the
electrons as well as their
localisation or delocalisation can be studied at the X-ray source BESSY
II, which offers powerful synchrotron radiation.
Experiment unlocks bizarre properties of strange metals.
International team finds unusual electrical behavior in material that
holds promise for new technology.
Alchemical Symbol - According to Paracelsus (1493–1541), the three
primes or tria prima – of which material substances are immediately
composed – are Mercury (Mind) ☿ - Salt (base matter or body) - Sulfur
(Soul). Western alchemy makes use of the Hermetic
elements. The
symbols used for these are: Air, Earth, Fire, Water.
Alchemy Symbols.
Seven Planetary Metals - Lead dominated by
Saturn ♄ - Tin dominated by Jupiter ♃ -Iron dominated by Mars ♂ - Gold
dominated by Sol ☉ - Copper dominated by Venus ♀ - Mercury (quicksilver)
dominated by Mercury ☿ - Silver dominated by Moon ☽.
Mundane Elements - Antimony ♁ - Arsenic -
Bismuth - Boron - Lithium - Magnesium - Phosphorus - Platinum ☽☉ -
Potassium -
Sulfur - Zinc.
Alchemical
Compounds - Sal ammoniac (ammonium chloride) - Aqua fortis (nitric
acid) - Aqua regia (nitro-hydrochloric acid) - Spirit of wine
(concentrated ethanol; also called aqua vitae) - Amalgam (alloys of a
metal and mercury) - Cinnabar (mercury sulfide) - Vitriol (sulfates).
Tetrataenite is a native metal composed of chemically-ordered
L10-type FeNi, recognized as a mineral in 1980. The
mineral is named after its tetragonal crystal structure and its
relation to the iron-nickel alloy, taenite. It is one of the mineral
phases found in meteoric iron. Tetrataenite forms naturally in iron
meteorites that contain taenite that are slow-cooled at a rate of a few
degrees per million years, which allows for ordering of the Fe and Ni
atoms. It is found most abundantly in slow-cooled chondrite meteorites,
as well as in mesosiderites. At high (as much as 52%) Ni content and
temperatures below 320 °C (the order-disorder transition temperature),
tetrataenite is broken down from taenite and distorts its face centered
cubic crystal structure to form the tetragonal L10 structure. Mixing
iron, nickel and phosphorus together in specific quantities forms
tetrataenite in seconds. The L10 phase can be synthetically produced by
neutron- or electron-irradiation of FeNi below 593 K, by
hydrogen-reduction of nanometric NiFe2O4, or by crystallization of Fe-Ni
alloys in the presence of traces of phosphorus. In 2015, it was reported
that tetrataenite was found in a terrestrial rock - a magnetite body from
the Indo-Myanmar ranges of northeast India. Tetrataenite has a highly
ordered crystal structure, appearing creamy in color and displaying
optical anisotropy. Its appearance is distinguishable from taenite, which
is dark gray with low reflectivity. FeNi easily forms into a cubic
crystal structure, but does not have magnetic anisotropy in this form.
Three variants of the L10 tetragonal crystal structure have been found,
as chemical ordering can occur along any of the three axes.
Philosopher Stone is a legendary alchemical substance
capable of turning
base metals such as mercury into
gold or silver. It
is also called the
elixir of life,
useful for rejuvenation and for achieving immortality; for many
centuries, it was the most sought goal in alchemy. The philosophers'
stone was the central symbol of the mystical terminology of alchemy,
symbolizing perfection at its finest, enlightenment, and heavenly bliss.
Efforts to discover the philosophers' stone were known as the Magnum Opus
("Great Work").
Philosopher King.
Magnum Opus is the process of working with the prima materia to
create the philosopher's stone. It has been used to describe personal and
spiritual transmutation in the Hermetic tradition, attached to laboratory
processes and chemical color changes, used as a model for the
individuation process, and as a device in art and literature.
Metamaterial
is a
material engineered to have a property that is
not found in nature.
They are made from assemblies of multiple elements fashioned from
composite materials such as metals or plastics.
Bio-Mimicry.
Lignin separation method could make renewable material profitable. A
novel method to extract lignin could help spin wheat straw into gold.
Lignin produced using the new method was color-neutral, odorless and
homogenous, an advance that could make this carbon-neutral material a
more viable candidate for development of high-value products. Researchers
extracted up to 93%
lignin
with up to 98% purity from wheat straw, producing a significant amount of
material in a uniform way that could make it more attractive for industry
use.
Metallurgy -
Metal Working
-
Materials Science -
Load
Capacities -
Strengths
Base Metal is
a common and
inexpensive metal, as opposed to a
precious metal such as
gold or silver.
A long-time goal of alchemists was the transmutation of a base (low
grade) metal into a precious metal. In numismatics, coins often derived
their value from the precious metal content; however, base metals have
also been used in coins in the past and today.