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law of simple multiple proportions

(Encyclopedia)law of simple multiple proportions, in chemistry, the statement that when two or more elements form more than one compound, the ratio of the weights of one element that combine with a given weight of ...

Rutherford, Ernest Rutherford, 1st Baron

(Encyclopedia)Rutherford, Ernest Rutherford, 1st Baron, 1871–1937, British physicist, b. New Zealand. Rutherford left New Zealand in 1895, having earned three degrees from the Univ. of New Zealand but having fail...

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...

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. ...