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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...

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)....

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. ...

bromide

(Encyclopedia)bromide, any of a group of compounds that contain bromine and a more electropositive element or radical. Bromides are formed by the reaction of bromine or a bromide with another substance; they are wi...

cellophane

(Encyclopedia)cellophane, thin, transparent sheet or tube of regenerated cellulose. Cellophane is used in packaging and as a membrane for dialysis. It is sometimes dyed and can be moisture-proofed by a thin coating...

tellurium

(Encyclopedia)tellurium tĕlo͝orˈēəm [key] [Lat.,=earth], semimetallic chemical element; symbol Te; at. no. 52; at. wt. 127.60; m.p. 450℃; b.p. 990℃; sp. gr. 6.24 at 20℃; valence −2, +4, or +6. Telluriu...