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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 ...

Franck, James

(Encyclopedia)Franck, James frängk [key], 1882–1964, German physicist. He was professor of physics at Göttingen and at Johns Hopkins (1935–38) and professor of physical chemistry at the Univ. of Chicago from ...

methyl

(Encyclopedia)methyl mĕthˈəl [key], CH3, organic free radical or alkyl group derived from methane by the removal of one hydrogen atom. ...

phenyl

(Encyclopedia)phenyl fĕnˈəl [key], C6H5, organic free radical or alkyl group derived from benzene by removing one hydrogen atom. ...

ethyl

(Encyclopedia)ethyl ĕthˈəl [key], CH3CH2, organic free radical or alkyl group derived from ethane by removing one hydrogen atom. ...

Hecht, Selig

(Encyclopedia)Hecht, Selig, 1892–1947, American biophysicist, b. Glogow, Austria (now Poland). He moved to the United States in 1898 and was graduated from the College of the City of New York (B.S., 1913) and fro...

oxy group

(Encyclopedia)oxy group ŏkˈsē [key], in chemistry, functional group that consists of an oxygen atom joined by single bonds to two separate alkyl groups or aryl groups. It is the functional group of ethers. ...

Le Bel, Joseph Achille

(Encyclopedia)Le Bel, Joseph Achille zhôsĕfˈ äshēlˈ ləbĕl [key], 1847–1930, French chemist. He was educated at the École polytechnique and carried out much of his research in his own private laboratory. ...

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...

ligand

(Encyclopedia)ligand lĭgˈənd [key], charged or uncharged molecule with one or more unshared pairs of electrons that can attach to a central metallic atom or ion to form an aggregate known as a complex ion (see c...