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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...

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...

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...

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