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molecule

(Encyclopedia)molecule mŏlˈəkyo͞ol [key] [New Lat.,=little mass], smallest particle of a compound that has all the chemical properties of that compound. A single atom is usually not referred to as a molecule, a...

chiral molecule

(Encyclopedia)chiral molecule, another term for optical isomer. See Stereoisomers under isomer. ...

molecular orbital theory

(Encyclopedia)molecular orbital theory, detailed explanation of how electrons are distributed in stable molecules. In the simpler valence theory of the chemical bond, each atom in a molecule is assumed to retain it...

photochemistry

(Encyclopedia)photochemistry, study of chemical processes that are accompanied by or catalyzed by the emission or absorption of visible light or ultraviolet radiation. A molecule in its ground (unexcited) state can...

urea

(Encyclopedia)CE5 urea yo͝oēˈə [key], organic compound that is the principal end product of nitrogen metabolism in most mammals. Urea was the first animal metabolite to be isolated in crystalline form; its c...

chloroprene

(Encyclopedia)chloroprene klōrˈəprēnˌ [key] or 2-chloro-1,3-butadiene, colorless liquid organic compound used in the synthesis of neoprene and certain other rubbers. The structure of the chloroprene molecule i...

free radical

(Encyclopedia)free radical, in chemistry, a molecule or atom that contains an unpaired electron but is neither positively nor negatively charged. Free radicals are usually highly reactive and unstable. They are pro...

Furchgott, Robert Francis

(Encyclopedia)Furchgott, Robert Francis, 1916–2009, American biochemist, b. Charleston, S.C., Ph.D. Northwestern Univ., 1940. Furchgott spent his entire career as a professor (1956–89) at the State Univ. of New...

functional group

(Encyclopedia)CE5 functional group, in organic chemistry, group of atoms within a molecule that is responsible for certain properties of the molecule and reactions in which it takes part. Organic compounds are f...

hemoglobin

(Encyclopedia)hemoglobin hēˈməglōˌbĭn [key], respiratory protein found in the red blood cells (erythrocytes) of all vertebrates and some invertebrates. A hemoglobin molecule is composed of a protein group, kn...