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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 ...

methyl

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

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 ...

phenyl

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

ethyl

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

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. ...

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. ...

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...

aromatic compound

(Encyclopedia)aromatic compound, any of a large class of compounds that includes benzene and compounds that resemble benzene in certain of their chemical properties. Originally applied to a small class of pleasant-...