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lime, chemical compound

(Encyclopedia)lime: see calcium oxide.

molybdenum

(Encyclopedia)molybdenum məlĭbˈdənəm [key] [Gr.,=leadlike], metallic chemical element; symbol Mo; at. no. 42; at. wt. 95.96; m.p. about 2,617℃; b.p. about 4,612℃; sp. gr. 10.22 at 20℃; valence +2, +3, +4...

Orsk

(Encyclopedia)Orsk ôrsk [key], city (1989 pop. 271,000), Orenburg region, in the foothills of the S Ural Mts., central Russia, on the Ural River. It is the center of the Orsk-Khalilovo industrial area, which has r...

Tm

(Encyclopedia)Tm, chemical symbol for the element thulium. ...

flame test

(Encyclopedia)flame test, test used in the identification of certain metals. It is based on the observation that light emitted by any element gives a unique spectrum when passed through a spectroscope. When a salt ...

mass number

(Encyclopedia)mass number, often represented by the symbol A, the total number of nucleons (neutrons and protons) in the nucleus of an atom. All atoms of a chemical element have the same atomic number (number of pr...

silver

(Encyclopedia)silver, metallic chemical element; symbol Ag [Lat. argentum]; at. no. 47; at. wt. 107.8682; m.p. 961.93℃; b.p. 2,212℃; sp. gr. 10.5 at 20℃; valence +1 or +2. Pure silver is nearly white, lustrou...

leaching

(Encyclopedia)leaching, method of extraction in which a solvent is passed through a mixture to remove some desired substance from it. A simple example is the passage of boiling water through ground coffee to dissol...

terbium

(Encyclopedia)terbium tûrˈbēəm [key] [from Ytterby, a village in Sweden], metallic chemical element; symbol Tb; at. no. 65; at. wt. 158.92535; m.p. 1,356℃; b.p. 3,123℃; sp. gr. about 8.25; valence +3 or +4....

einsteinium

(Encyclopedia)einsteinium īnˈstīˌnēəm, īnstīˈ– [key] [for Albert Einstein], artificially produced radioactive chemical element; symbol Es; at. no. 99; mass no. of most stable isotope 252; m.p. about 860�...