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Cd, chemical symbol

(Encyclopedia)Cd, symbol for the element cadmium. ...

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,...

Pd

(Encyclopedia)Pd, symbol for the element palladium. ...

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...

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...

Organization for the Prohibition of Chemical Weapons

(Encyclopedia)Organization for the Prohibition of Chemical Weapons (OPCW), international body (est. 1997) responsible for the implementation of the Chemical Weapons Convention (CWC), which aims at the destruction o...

ruthenium

(Encyclopedia)ruthenium ro͞othēˈnēəm [key], metallic chemical element; symbol Ru; at. no. 44; at. wt. 101.07; m.p. about 2,310℃; b.p. about 3,900℃; sp. gr. 12.41 at 20℃; valence commonly +2, +3, +4, +6, ...

platinum

(Encyclopedia)platinum plătˈənəm [key], metallic chemical element; symbol Pt; at. no. 78; at. wt. 195.084; m.p. 1,772℃; b.p. 3,827±100℃; sp. gr. 21.45 at 20℃; valence +2 or +4. Pure platinum is a malleab...