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radium
(Encyclopedia)radium rāˈdēəm [key] [Lat. radius=ray], radioactive metallic chemical element; symbol Ra; at. no. 88; mass number of most stable isotope 226; m.p. 700℃; b.p. 1,140℃; sp. gr. about 6.0; valence...ytterbium
(Encyclopedia)ytterbium ĭtûrˈbēəm [key] [for Ytterby, a town in Sweden], metallic chemical element; symbol Yb; at. no. 70; at. wt. 173.054; m.p. 819℃; b.p. about 1,194℃; sp. gr. about 7.0; valence +2 or +3...americium
(Encyclopedia)americium ămərĭˈshēəm [key], artificially produced radioactive chemical element; symbol Am; at. no. 95; mass no. of most stable isotope 243; m.p. about 1,175℃; b.p. about 2,600℃; sp. gr. 13....mica
(Encyclopedia)mica mīˈkə [key], general term for a large group of minerals, hydrous silicates of aluminum and potassium, often containing magnesium, ferrous iron, ferric iron, sodium, and lithium and more rarely...feldspar
(Encyclopedia)feldspar fĕlˈspär [key], an abundant group of rock-forming minerals which constitute 60% of the earth's crust. Chemically the feldspars are silicates of aluminum, containing sodium, potassium, iron...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, ...nitrate
(Encyclopedia)nitrate, chemical compound containing the nitrate (NO3) radical. Nitrates are salts or esters of nitric acid, HNO3, formed by replacing the hydrogen with a metal (e.g., sodium or potassium) or a radic...silicate
(Encyclopedia)silicate, chemical compound containing silicon, oxygen, and one or more metals, e.g., aluminum, barium, beryllium, calcium, iron, magnesium, manganese, potassium, sodium, or zirconium. Silicates may b...titanium
(Encyclopedia)titanium tītāˈnēəm, tĭ– [key] [from Titan], metallic chemical element; symbol Ti; at. no. 22; at. wt. 47.867; m.p. 1,675℃; b.p. 3,260℃; sp. gr. 4.54 at 20℃; valence +2, +3, or +4. Titani...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...Browse by Subject
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