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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...

multiple chemical sensitivity

(Encyclopedia)multiple chemical sensitivity (MCS), adverse physical reaction to certain chemicals in susceptible persons. When exposed to the chemicals, people with MCS react with symptoms such as nausea, headache,...

Mace, chemical spray

(Encyclopedia)Mace, chemical spray device used by police in riot control. Mace is ordinary tear gas (chloroacetophenone, or CN) in a volatile solvent contained in a spray can. It causes severe lacrimation and tempo...

magnesia, chemical compound

(Encyclopedia)magnesia, common name for the chemical compound magnesium oxide, MgO. It occurs as colorless, cubic crystals. It is refractory, melting at about 2,800℃. It is very slightly soluble in pure water but...

CS, chemical compound

(Encyclopedia)CS, chemical compound (orthochlorobenzalmalonitrile) used in riot control and, by the military, as a harassing agent. The compound is dispersed as an aerosol or as a finely divided powder. Exposure to...

copper, chemical element

(Encyclopedia)copper, metallic chemical element; symbol Cu [Lat. cuprum=copper]; at. no. 29; at. wt. 63.546; m.p. 1,083.4℃; b.p. 2,567℃; sp. gr. 8.96 at 20℃; valence +1 or +2. Copper and some of its alloys ha...

palladium, chemical element

(Encyclopedia)palladium [Gr. Pallas, goddess of wisdom], metallic chemical element; symbol Pd; at. no. 46; at. wt. 106.42; m.p. 1,554℃; b.p. 2,970℃; sp. gr. 12.02 at 20℃; valence +2, +3, or +4. Palladium is a...

mercury, chemical element

(Encyclopedia)mercury or quicksilver [from the Roman god Mercury], metallic chemical element; symbol Hg [Lat. hydrargyrum=liquid silver]; at. no. 80; at. wt. 200.59; m.p. −38.842℃; b.p. 356.58℃; sp. gr. 13.55...

cobalt, chemical element

(Encyclopedia)cobalt, metallic chemical element; symbol Co; at. no. 27; at. wt. 58.9332; m.p. 1,495℃; b.p. about 2,870℃; sp. gr. 8.9 at 20℃; valence +2 or +3. Cobalt is a silver-white, lustrous, hard, brittle...

alkyne

(Encyclopedia)CE5 Alkynes alkyne ălˈkīn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). Alkynes with one triple bond have t...