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mordant

(Encyclopedia)mordant môrˈdənt [key] [Fr.,=biting], substance used in dyeing to fix certain dyes (mordant dyes) in cloth. Either the mordant (if it is colloidal) or a colloid produced by the mordant adheres to t...

vitamin

(Encyclopedia)vitamin, group of organic substances that are required in the diet of humans and animals for normal growth, maintenance of life, and normal reproduction. Vitamins act as catalysts; very often either t...

LSD

(Encyclopedia)LSD or lysergic acid diethylamide līˌsûrˈjĭk, dīˌĕthˈələmĭd, dīˌĕthəlămˈĭd [key], alkaloid synthesized from lysergic acid, which is found in the fungus ergot (Claviceps purpurea). I...

cyclamate

(Encyclopedia)cyclamate sīˌkləmātˌ, –mət [key], any member of a group of salts of cyclamic acid (cyclohexanesulfamic acid). The sodium and calcium salts were commonly used as artificial sweeteners until 196...

fulminate

(Encyclopedia)fulminate fŭlˈmĭnāt [key], any salt of fulminic acid, HONC, a highly unstable compound known only in solution. The term is most commonly applied to the explosive mercury (II) fulminate, also calle...

buffer

(Encyclopedia)buffer, solution that can keep its relative acidity or alkalinity constant, i.e., keep its pH constant, despite the addition of strong acids or strong bases. Buffer solutions are frequently solutions ...

pyrogallol

(Encyclopedia)pyrogallol –ĭk [key], C6H6O3, white, crystalline, aromatic compound with a biting taste; it is poisonous. It melts at 133℃ and boils at 309℃. In alkaline solution it is an active reducing agent...

ester

(Encyclopedia)CE5 Esters ester, any one of a group of organic compounds with general formula RCO2R′ (where R and R′ are alkyl groups or aryl groups) that are formed by the reaction between an alcohol and an...

cryolite

(Encyclopedia)cryolite or kryolite both: krīˈəlītˌ [key] [Gr.,=frost stone], mineral usually pure white or colorless but sometimes tinted in shades of pink, brown, or even black and having a luster like that o...

gastric juice

(Encyclopedia)gastric juice, thin, strongly acidic (pH varying from 1 to 3), almost colorless liquid secreted by the glands in the lining of the stomach. Its essential constituents are the digestive enzymes pepsin ...