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ruby

(Encyclopedia)ruby, precious stone, the transparent red variety of corundum, found chiefly in Myanmar, Thailand, and Sri Lanka and classified among the most valuable of gems. The Myanmarese stones are blood red, th...

potassium chloride

(Encyclopedia)potassium chloride, chemical compound, KCl, a colorless or white, cubic, crystalline compound that closely resembles common salt (sodium chloride). It is soluble in water, alcohol, and alkalies. Potas...

gadolinium

(Encyclopedia)gadolinium gădəlĭnˈēəm [key], metallic chemical element; symbol Gd; at. no. 64; at. wt. 157.25; m.p. 1,312℃; b.p. 3,233℃; sp. gr. 7.898 at 25℃; valence +3. Gadolinium is a malleable, ducti...

nitrogen

(Encyclopedia)nitrogen nīˈtrəjən [key], gaseous chemical element; symbol N; at. no. 7; interval in which at. wt. ranges 14.00643–14.00728; m.p. −209.86℃; b.p. −195.8℃; density 1.25 grams per liter at ...

sulfuric acid

(Encyclopedia)sulfuric acid, chemical compound, H2SO4, colorless, odorless, extremely corrosive, oily liquid. It is sometimes called oil of vitriol. Although sulfuric acid is now one of the most widely used c...

calcium hydroxide

(Encyclopedia)calcium hydroxide, Ca(OH)2, colorless crystal or white powder. It is prepared by reacting calcium oxide (lime) with water, a process called slaking, and is also known as hydrated lime or slaked lime. ...

lime, chemical compound

(Encyclopedia)lime: see calcium oxide.

limelight

(Encyclopedia)limelight: see calcium oxide.

quicklime

(Encyclopedia)quicklime: see calcium oxide.

Drummond light

(Encyclopedia)Drummond light: see calcium oxide. ...