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Butlerov, Aleksandr Mikhailovich

(Encyclopedia)Butlerov, Aleksandr Mikhailovich əlyĭksänˈdər mēkhīlˈəvĭch bo͞otˈlyərôf [key], 1825–86, Russian chemist. As professor at the Univ. of Kazan he founded the first school of Russian chemi...

physical chemistry

(Encyclopedia)physical chemistry, branch of science that combines the principles and methods of physics and chemistry. It provides a fundamental theoretical and experimental basis for all of chemistry, including or...

stereochemistry

(Encyclopedia)stereochemistry, study of the three-dimensional configuration of the atoms that make up a molecule and the ways in which this arrangement affects the physical and chemical properties of the molecule. ...

Zewail, Ahmed Hassan

(Encyclopedia)Zewail, Ahmed Hassan, 1946–2016, Egyptian-American chemist, b. Damanhur, Egypt, Ph.D. Univ. of Pennsylvania, 1974. He became a U.S. citizen in 1982. A professor at the California Institute of Techno...

nucleus, in physics

(Encyclopedia)nucleus, in physics, the extremely dense central core of an atom. Following the discovery of radioactivity by A. H. Becquerel in 1896, Ernest Rutherford identified two types of radiation given off b...

phosphorus

(Encyclopedia)phosphorus fŏsˈfərəs [key] [Gr.,=light-bearing], nonmetallic chemical element; symbol P; at. no. 15; at. wt. 30.97376; m.p. 44.1℃; b.p. about 280℃; sp. gr. 1.82 at 20℃; valence −3, +3, or ...

chlorine

(Encyclopedia)chlorine klōrˈēn, klôrˈ– [key] [Gr.,=green], gaseous chemical element; symbol Cl; at. no. 17; interval in which at. wt. ranges 35.446–35.457; m.p. −100.98℃; b.p. −34.6℃; density 3.2 g...

Köthen

(Encyclopedia)Köthen köˈtən [key], city (1994 pop. 31,860), Saxony-Anhalt, central Germany. Köthen has lignite mines, sugar refineries, textile mills, chemical factories, and heavy engineering industries. The ...

Chain, Ernst Boris

(Encyclopedia)Chain, Ernst Boris, 1906–79, English biochemist, b. Berlin, Germany. In 1933 he left Germany and went to England, where he conducted research at Cambridge from 1933 to 1935 and at Oxford from 1935; ...

Onsager, Lars

(Encyclopedia)Onsager, Lars, 1903–76, American physical chemist, b. Oslo, Ph.D. Yale, 1935. Onsager taught at Brown Univ. from 1928 to 1933 and was on the faculty at Yale from 1933 until his retirement in 1972. H...