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ethanol

(Encyclopedia)ethanol ĕthˈənōlˌ [key] or ethyl alcohol, CH3CH2OH, a colorless liquid with characteristic odor and taste; commonly called grain alcohol or simply alcohol. Ethanol is used extensively as a solv...

oxidation and reduction

(Encyclopedia)oxidation and reduction, complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation was used to re...

Heck, Richard Fred

(Encyclopedia)Heck, Richard Fred, 1931–2015, American chemist, b. Springfield, Mass., Ph.D. Univ. of California, Los Angeles, 1954. Heck was a researcher at the Hercules Corporation in Wilmington, Del., from 1957...

isomer

(Encyclopedia)isomer īˈsəmər [key], in chemistry, one of two or more compounds having the same molecular formula but different structures (arrangements of atoms in the molecule). Isomerism is the occurrence of ...

antacid

(Encyclopedia)antacid, any one of several basic substances that counteract stomach acidity (see stomach). Antacids are used by physicians to treat hyperchlorhydria, i.e., the excessive production of hydrochloric ac...

hardpan

(Encyclopedia)hardpan, condition of the soil or subsoil in which the soil grains become cemented together by such bonding agents as iron oxide and calcium carbonate, forming a hard, impervious mass. It is disadvant...

Lappeenranta

(Encyclopedia)Lappeenranta läpˈpānränˌtä [key], Swed. Villmanstrand, city (1998 pop. 57,374), Southern Finland prov., SE Finland, on Lake Saimaa. It is an important trade and industrial center, with sulfuric ...

salicylate

(Encyclopedia)salicylate səlĭsˈəlātˌ [key], any of a group of analgesics, or painkilling drugs, that are derivatives of salicylic acid. The best known is acetylsalicylic acid, or aspirin. Now often made synth...

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...

Lydd

(Encyclopedia)Lydd lĭd [key], town (1991 pop. 4,721), Kent, SE England. A military training center, Lydd gave its name to lyddite (picric acid), an explosive that was tested at the military camp there in 1888. Lyd...