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organic chemistry

(Encyclopedia)organic chemistry, branch of chemistry dealing with the compounds of carbon. While it is only the fourteenth most common element on earth, carbon forms by far the greatest number of different compound...

valence, in chemistry

(Encyclopedia)valence, combining capacity of an atom expressed as the number of single bonds the atom can form or the number of electrons an element gives up or accepts when reacting to form a compound. Atoms are c...

ion, in chemistry

(Encyclopedia)ion, atom or group of atoms having a net electric charge. Ionization has many applications. Vapor lamps and fluorescent lamps take advantage of the light given off when positive ions recombine with ...

ether, in chemistry

(Encyclopedia)CE5 Ethers ether, any of a number of organic compounds whose molecules contain two hydrocarbon groups joined by single bonds to an oxygen atom. The most common of these compounds is ethyl ether, C...

sublimation, in chemistry

(Encyclopedia)sublimation sŭblĭmāˈshən [key], change of a solid substance directly to a vapor without first passing through the liquid state. The term is also used to describe the reverse process of the gas ch...

surface chemistry

(Encyclopedia)surface chemistry, study of chemical reactions in which the reactants are first adsorbed onto a surface medium (see adsorption) that then acts as a catalyst for the reaction; after the reaction the pr...

organometallic chemistry

(Encyclopedia)organometallic chemistry, the reactions and use of a class of compounds (R-M) that contain a covalent bond between carbon and metal. They are prepared either by direct reaction of the metal with an or...

emanation, in chemistry

(Encyclopedia)emanation: see radon.

International Union of Pure and Applied Chemistry

(Encyclopedia)International Union of Pure and Applied Chemistry (IUPAC), an international organization est. 1919 to advance the chemical sciences and contribute to the application of chemistry to the service of hum...

concentration

(Encyclopedia)concentration, in chemistry, measure of the relative proportions of two or more quantities in a mixture. The concentration of a solute is very important in studying chemical reactions because it deter...