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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Glossary of chemistry terms | 5/20 | https://en.wikipedia.org/wiki/Glossary_of_chemistry_terms | reference | science, encyclopedia | 2026-05-05T07:59:20.572989+00:00 | kb-cron |
chemical decomposition The breakdown of a single particle or entity (such as a molecule or reactive intermediate) into two or more fragments, or a chemical reaction in which two or more products are formed from a single reactant. Contrast chemical synthesis.
chemical element See element.
chemical formula Any of various means of concisely displaying information about the chemical composition of a compound or molecule using letters, numbers, and/or typographical symbols. Chemical formulas, such as empirical and molecular formulas, can only indicate the identities and numerical proportions of the atoms in a compound and are therefore more limited in descriptive power than chemical names and structural formulas.
chemical law A law of nature relevant to chemistry, such as the law of conservation of mass.
chemical nomenclature
chemical physics
chemical process
- Any method or means of changing one or more chemicals or chemical compounds in any way, either naturally or artificially, spontaneously or by the actions of external forces.
- In chemical engineering, any method used on an industrial scale (especially in manufacturing) to change the composition of one or more chemicals or materials.
chemical reaction The change of one or more substances into one or more different substances.
chemical species Also simply called a chemical. A chemical substance or ensemble of substances composed of chemically identical molecular entities which can explore the same set of molecular energy levels on a characteristic or delineated time scale.
chemical substance Also pure substance or simply substance. A form of matter that has constant chemical composition and characteristic properties and which cannot be separated into simpler components by purely physical methods (i.e. without breaking chemical bonds). It is often called a pure substance to distinguish it from a mixture.
chemical synthesis The artificial execution of one or more chemical reactions in order to obtain one or more products. In modern laboratory contexts, specific chemical syntheses are both reliable and reproducible.
chemistry The scientific discipline that studies chemical substances, compounds, and molecules composed of atoms of various chemical elements, as well as their compositions, structures, properties, behaviors, and the changes they undergo during reactions with other substances.
chirality A property of asymmetry in which a molecule or ion is distinguishable from its mirror image such that it cannot be superposed upon it by any combination of geometric rotations, translations, or some conformational changes. Such a molecule or ion is said to be chiral, and exists in two forms, known as enantiomers, which are stereoisomers of each other; these forms are distinguished as either "right-handed" or "left-handed" by their absolute configuration or some other criterion. Several different types of asymmetry can give rise to chirality, most commonly when molecules possess stereogenic elements such as one or more stereocenters (central chirality), a stereogenic axis (axial chirality), or a stereogenic plane (planar chirality); additionally, the inherent curvature of a molecule can cause it to possess inherent chirality.
chromatography Any of a variety of laboratory methods designed to separate a heterogeneous mixture into its component chemical species by first dissolving the mixture in a gas or liquid solvent called the mobile phase and then passing it through a system such as a chromatography column or a capillary tube upon which a material called the stationary phase is fixed. The different species present in the mixture have different affinities for and retention times upon the stationary phase, causing them to separate from the rest of the species in the moving fluid at characteristic rates. This phenomenon is exploited both to detect or measure the relative proportions of analytes present in a mixture, and to purify specific compounds.
chromometer See colorimeter.
cis–trans isomerism
closed system
cluster
cohesion The tendency of similar particles or surfaces to cling to one another as a result of intermolecular forces. Contrast adhesion.
colligative property Any property of a solution that depends upon the ratio of the number of solute particles to the number of solvent particles in the solution, and not on the nature of the chemical species present. Examples include osmotic pressure, freezing-point depression, and boiling-point elevation.
colloid A mixture in which microscopic insoluble particles are suspended within and evenly dispersed throughout another substance, usually a liquid but sometimes inclusive of aerosols and gels. Thus a colloid contains a dispersed phase and a continuous phase. Many milks are colloids.
color standard A liquid solution of known chemical composition and concentration, and hence of known and standardized color, used as a reference in the optical analysis of samples of unknown strength.
color test The quantitative analysis of a substance by comparing the intensity of the color produced when the substance is exposed to a reagent with a standard color produced similarly in a solution of known strength.
colorimeter Also chromometer. Any instrument used for color measurement based on optical comparison with standard colors, particularly a device used in colorimetry that measures the absorbance of specific wavelengths of light by a given solution in order to determine the concentration of a known solute in the solution, by application of the principle that solute concentration is directly proportional to absorbance.
combustion An exothermic reaction between an oxidant and a fuel that produces large amounts of heat and often light.
Commission on Isotopic Abundances and Atomic Weights (CIAAW)
complex A molecular entity formed by loose association between two or more component molecular entities (ionic or uncharged), or the corresponding chemical species. The bonding between the components is normally weaker than in a covalent bond. See also coordination complex.
compound A substance that is made up of two or more chemically bonded elements.
Compton rule An empirical law of physical chemistry which states that the heat of fusion of a given element multiplied by its atomic weight and then divided by its melting point in kelvin is always equal to approximately 2.
concatemer