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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...

manganese

(Encyclopedia)manganese măngˈgənēs, mănˈ– [key] [Lat.,=magnet], metallic chemical element; symbol Mn; at. no. 25; at. wt. 54.93805; m.p. about 1,244℃; b.p. about 1,962℃; sp. gr. 7.2 to 7.45, depending o...

gold

(Encyclopedia)gold, metallic chemical element; symbol Au [Lat. aurum=shining dawn]; at. no. 79; at. wt. 196.96657; m.p. 1,064.43℃; b.p. 2,808℃; sp. gr. 19.32 at 20℃; valence +1 or +3. Gold is very ductile and...

potassium

(Encyclopedia)potassium pətăsˈēəm [key], a metallic chemical element; symbol K [Lat. kalium=alkali]; at. no. 19; at. wt. 39.0983; m.p. 63.25℃; b.p. 760℃; sp. gr. .862 at 20℃; valence +1. Potassium is a s...

calcium

(Encyclopedia)calcium kălˈsēəm [key] [Lat.,=lime], metallic chemical element; symbol Ca; at. no. 20; at. wt. 40.078; m.p. about 839℃; b.p. 1,484℃; sp. gr. 1.55 at 20℃; valence +2. Calcium is a malleable, ...

copper, chemical element

(Encyclopedia)copper, metallic chemical element; symbol Cu [Lat. cuprum=copper]; at. no. 29; at. wt. 63.546; m.p. 1,083.4℃; b.p. 2,567℃; sp. gr. 8.96 at 20℃; valence +1 or +2. Copper and some of its alloys ha...

mining

(Encyclopedia)mining, extraction of solid mineral resources from the earth. These resources include ores, which contain commercially valuable amounts of metals, such as iron and aluminum; precious stones, such as d...

metallurgy

(Encyclopedia)metallurgy mĕtˈəlûrˌjē [key], science and technology of metals and their alloys. Modern metallurgical research is concerned with the preparation of radioactive metals, with obtaining metals econ...

acids and bases

(Encyclopedia)acids and bases, two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Another theory that provides a very broad ...

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