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sulfur dioxide

(Encyclopedia)sulfur dioxide, chemical compound, SO2, a colorless gas with a pungent, suffocating odor. It is readily soluble in cold water, sparingly soluble in hot water, and soluble in alcohol, acetic acid, and ...

casein

(Encyclopedia)casein kāˈsēn [key], well-defined group of proteins found in milk, constituting about 80% of the proteins in cow's milk, but only 40% in human milk. Casein is a remarkably efficient nutrient, suppl...

polyacrylics

(Encyclopedia)polyacrylics pŏlˌēəkrĭlˈĭks [key], group of thermoplastics that are transparent and highly decorative (see plastic). The polyacrylics, or acrylic plastics, are polymers (and copolymers) of deri...

phosphorus

(Encyclopedia)phosphorus fŏsˈfərəs [key] [Gr.,=light-bearing], nonmetallic chemical element; symbol P; at. no. 15; at. wt. 30.97376; m.p. 44.1℃; b.p. about 280℃; sp. gr. 1.82 at 20℃; valence −3, +3, or ...

salt, chemical compound

(Encyclopedia)salt, chemical compound (other than water) formed by a chemical reaction between an acid and a base (see acids and bases). Salts are also prepared by methods other than neutralization. A metal can c...

bacteriophage

(Encyclopedia)bacteriophage băktērˈēəfājˌ [key], virus that infects bacteria and sometimes destroys them by lysis, or dissolution of the cell. Bacteriophages, or phages, have a head composed of protein, an i...

Olympic Mountains

(Encyclopedia)Olympic Mountains, highest part of the Coast Ranges, on the Olympic Peninsula, NW Wash. Mt. Olympus (7,965 ft/2,427 m) is the highest point in the mountains, which are composed mainly of sedimentary r...

cytosine

(Encyclopedia)cytosine sīˈtōsēnˌ [key], organic base of the pyrimidine family. It was isolated from the nucleic acid of calf thymus tissue in 1894. A suggested structure for cytosine, published in 1903, was co...

histidine

(Encyclopedia)CE5 histidine hĭsˈtĭdēn [key], organic compound, one of the 22 α-amino acids commonly found in animal proteins. Only the l-stereoisomer appears in mammalian protein. Histidine is the direct pr...

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...