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tungsten

(Encyclopedia)tungsten tŭngˈstən [key] [Swed.,=heavy stone], metallic chemical element; symbol W; at. no. 74; at. wt. 183.84; m.p. about 3,410℃; b.p. 5,660℃; sp. gr. 19.3 at 20℃; valence +2, +3, +4, +5, or...

Kroto, Harry

(Encyclopedia)Kroto, Harry (Sir Harold Walter Kroto), 1939–2016, British chemist, b. Harold Walter Krotoschiner, Ph.D. Univ. of Sheffield, 1964. Kroto was the son of German parents who fled Nazi rule to England. ...

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...

Freon

(Encyclopedia)Freon frēˈŏn [key] [trade name], any one of a special class of chemical compounds that are used as refrigerants, aerosol propellants, and solvents. These compounds are haloalkanes, i.e., halogen de...

Grubbs, Robert Howard

(Encyclopedia)Grubbs, Robert Howard, 1942–2021, American chemist, b. near Possum Trot, Ky., Univ. of Florida (B.S., 1963; M.S., 1965), Columbia, Univ. (Ph.D, 1968)....

aliphatic compound

(Encyclopedia)aliphatic compound ălˌəfătˈĭk [key], any of a large class of organic compounds whose carbon atoms are joined together in straight or branched open chains rather than in rings. The hydrocarbons o...

alloy

(Encyclopedia)alloy ălˈoi, əloiˈ [key] [O. Fr.,=combine], substance with metallic properties that consists of a metal fused with one or more metals or nonmetals. Alloys may be a homogeneous solid solution, a he...

Curl, Robert Floyd, Jr.

(Encyclopedia)Curl, Robert Floyd, Jr., 1933–, American chemist, b. Alice, Tex., Ph.D. Univ. of California, Berkeley, 1957. Curl has been a professor at Rice Univ. in Houston, Tex., since 1958. In 1996 he was awar...

resuscitator

(Encyclopedia)resuscitator rĭsŭsˈĭtāˌtər [key], device used to revive a person whose normal breathing has been disrupted. Several types are in wide use. The automatic tank resuscitator consists of a face mas...

acid anhydride

(Encyclopedia)acid anhydride ănhīˈdrīd, –drəd [key], chemical compound that reacts with water to form an acid (see acids and bases). Anhydrides of inorganic acids are usually oxides of nonmetallic elements. ...