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rare earths

(Encyclopedia)rare earths, in chemistry, oxides of the rare-earth metals. They were once thought to be elements themselves. They are widely distributed in the earth's crust and are fairly abundant, although they we...

blackbody

(Encyclopedia)blackbody, in physics, an ideal black substance that absorbs all and reflects none of the radiant energy falling on it. Lampblack, or powdered carbon, which reflects less than 2% of the radiation fall...

iron

(Encyclopedia)iron, metallic chemical element; symbol Fe [Lat. ferrum]; at. no. 26; at. wt. 55.845; m.p. about 1,535℃; b.p. about 2,750℃; sp. gr. 7.87 at 20℃; valence +2, +3, +4, or +6. Iron is biologically s...

chlorate

(Encyclopedia)chlorate pərklōrˈāt, –klôrˈ– [key], salts of chloric acid, HClO3, and perchloric acid, HClO4, respectively. Perchlorates are safer to handle than chlorates; they are more stable when expos...

Libby, Willard Frank

(Encyclopedia)Libby, Willard Frank, 1908–80, American chemist, b. Grand Valley, Colo., grad. Univ. of California (B.S., 1931; Ph.D., 1933). He taught (1933–45) at the Univ. of California and was a chemist (1941...

Schrock, Richard Royce

(Encyclopedia)Schrock, Richard Royce, 1945–, American chemist, b. Berne, Ind., Ph.D Harvard, 1971. After working for three years with the Dupont Company, he became (1972) a professor at the Massachusetts Institut...

chloroform

(Encyclopedia)chloroform trīˌklôrōmĕthˈān [key], CHCl3, volatile, colorless, nonflammable liquid that has a sweetish taste and a somewhat pungent odor; it boils at 61.7℃. It dissolves freely in ethanol and...

Chauvin, Yves

(Encyclopedia)Chauvin, Yves, 1930–2015, French chemist, b. Menen, Belgium, grad. Lyon School of Chemistry, Physics, and Electronics (CPE), 1954. Chauvin was a research engineer (1960–91) and then research direc...

graphene

(Encyclopedia)graphene, virtually transparent, highly conductive carbon material in which the atoms are organized into a honeycomblike arrangement and form a thin sheet that is one atom thick. Andre Geim and Konsta...

formic acid

(Encyclopedia)formic acid or methanoic acid mĕthˌənōˈĭk [key], HCO2H, a colorless, corrosive liquid with a sharp odor; it boils at 100.7℃ and solidifies at 8.4℃. It has the lowest molecular weight and is ...