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calcium oxide

(Encyclopedia)calcium oxide, chemical compound, CaO, a colorless, cubic crystalline or white amorphous substance. It is also called lime, quicklime, or caustic lime, but commercial lime often contains impurities, e...

sweetener, artificial

(Encyclopedia)sweetener, artificial, substance used as a low-calorie sugar substitute. Saccharin, cyclamates, and aspartame have been the most commonly used artificial sweeteners. Saccharin, a coal-tar derivative t...

alum

(Encyclopedia)alum ălˈəm [key], any one of a series of isomorphous double salts that are hydrated sulfates of a univalent cation (e.g., potassium, sodium, ammonium, cesium, or thallium) and a trivalent cation (e...

aryl group

(Encyclopedia)aryl group ârˈĭl [key], in chemistry, group of atoms derived from benzene or from a benzene derivative by removing one hydrogen that is bonded to the benzene ring (see radical). The simplest aryl g...

threonine

(Encyclopedia)CE5 threonine thrēˈənēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. It is one of several essen...

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...

porcelain

(Encyclopedia)porcelain [Ital. porcellana], white, hard, permanent, nonporous pottery having translucence which is resonant when struck. Porcelain was first made by the Chinese to withstand the great heat generated...

cupric sulfate

(Encyclopedia)cupric sulfate ko͞oˈprĭk sŭlˈfāt, kyo͞oˈ– [key] or copper (II) sulfate, chemical compound, CuSO4, taking the form of white rhombohedral crystals or amorphous powder. It decomposes at 650℃ ...

cyanide

(Encyclopedia)cyanide sīˈənīdˌ [key], chemical compound containing the cyano group, –CN. Cyanides are salts or esters of hydrogen cyanide (hydrocyanic acid, HCN) formed by replacing the hydrogen with a metal...

hydrogen cyanide

(Encyclopedia)hydrogen cyanide, HCN, colorless, volatile, and extremely poisonous chemical compound whose vapors have a bitter almond odor. It melts at −14℃ and boils at 26℃. It is miscible in all proportions...