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chromium

(Encyclopedia)chromium krōˈmēəm [key] [Gr.,=color], metallic chemical element; symbol Cr; at. no. 24; at. wt. 51.9961; m.p. about 1,857℃; b.p. 2,672℃; sp. gr. about 7.2 at 20℃; valence +2, +3, +6. Chromiu...

bromine

(Encyclopedia)bromine brōˈmēn, –mĭn [key] [Gr.,=stench], volatile, liquid chemical element; symbol Br; at. no. 35; at. wt. 79.904; m.p. –7.2℃; b.p. 58.78℃; sp. gr. of liquid 3.12 at 20℃; density of va...

catalyst

(Encyclopedia)catalyst, substance that can cause a change in the rate of a chemical reaction without itself being consumed in the reaction; the changing of the reaction rate by use of a catalyst is called catalysis...

classification

(Encyclopedia)CE5 classification, in biology, the systematic categorization of organisms into a coherent scheme. The original purpose of biological classification, or systematics, was to organize the vast number...

curry

(Encyclopedia)curry [Malayalam], condiment much used in India and elsewhere in Asia and the Middle East, in combination with rice, meat, and a variety of other dishes. It is compounded of such spices as turmeric, f...

Lynen, Feodor

(Encyclopedia)Lynen, Feodor fāōˈdôr lēˈnən [key], 1911–79, German biochemist, grad. Univ. of Munich (Ph.D. 1937). He began teaching at the Max Planck Institute for Cell Chemistry in Munich in 1947. His res...

lead acetate

(Encyclopedia)lead acetate, chemical compound, a white crystalline substance with a sweetish taste. Like other lead compounds, it is very poisonous. Lead acetate is soluble in water and glycerin. With water it form...

cautery

(Encyclopedia)cautery, searing or destruction of living animal tissue by use of heat or caustic chemicals. In the past, cauterization of open wounds, even those following amputation of a limb, was performed with ho...

prosthetic group

(Encyclopedia)prosthetic group, non-amino acid portions of certain protein molecules. The key part of the prosthetic group may be either organic (such as a vitamin) or inorganic (such as a metal) and is usually req...

Hemings, Sally

(Encyclopedia)Hemings, Sally, 1773–1835, African-American slave owned by Thomas Jefferson, b. Charles City co., Va.; her original name was probably Sarah. Her father was John Wayles, Jefferson's father-in-law; he...