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phenolphthalein

(Encyclopedia)phenolphthalein fēˈnôlthălˈēən [key], or 2,2-Bis(p-hydroxyphenyl) phthalide, C20H14O4, crystalline organic compound. It is used medicinally as a laxative and is widely employed in the laborator...

amino group

(Encyclopedia)amino group, in chemistry, functional group that consists of a nitrogen atom attached by single bonds to hydrogen atoms, alkyl groups, aryl groups, or a combination of these three. An organic compound...

chloroprene

(Encyclopedia)chloroprene klōrˈəprēnˌ [key] or 2-chloro-1,3-butadiene, colorless liquid organic compound used in the synthesis of neoprene and certain other rubbers. The structure of the chloroprene molecule i...

ammonium group

(Encyclopedia)ammonium group, in chemistry, a positively charged nitrogen atom joined by single bonds to four other atoms or groups. The simplest ammonium group, NH4+, is formed by protonation of ammonia, NH3, e.g....

asparagine

(Encyclopedia)CE5 asparagine əspârˈəjēn [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer participates in the biosynthesis of mammalian proteins. ...

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)....

adenosine monophosphate

(Encyclopedia)adenosine monophosphate (AMP) ədĕnˈəsēn mŏnˌəfŏsˈfāt [key], organic compound composed of an adenine base, the sugar ribose, and one phosphate unit. AMP is one of the possible products of th...

herbicide

(Encyclopedia)herbicide hrˈbəsīdˌ [key], chemical compound that kills plants or inhibits their normal growth. A herbicide in a particular formulation and application can be described as selective or nonselectiv...

glutamic acid

(Encyclopedia)CE5 glutamic acid glo͞otămˈĭk [key], organic compound, one of the 20 amino acids commonly found in animal proteins. Only the l-stereoisomer occurs in mammalian proteins. Like aspartic acid, glu...

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...

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