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Ac, chemical symbol

(Encyclopedia)Ac, symbol for the element actinium. ...

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...

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...

La, chemical symbol

(Encyclopedia)La, symbol for the element lanthanum. ...

lead, chemical element

(Encyclopedia)lead, metallic chemical element; symbol Pb [Lat. plumbum]; at. no. 82; at. wt. 207.2; m.p. 327.502℃; b.p. about 1,740℃; sp. gr. 11.35 at 20℃; valence +2 or +4. One of the oldest metals used by h...

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...

Re, chemical symbol

(Encyclopedia)Re, symbol for the element rhenium. ...

Tb, chemical symbol

(Encyclopedia)Tb, symbol for the element terbium. ...

sulphur, chemical element

(Encyclopedia)sulphur: see sulfur.