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cesium
(Encyclopedia)cesium sēˈzēəm [key] [Lat.,=bluish gray], a metallic chemical element; symbol Cs; at. no. 55; at. wt. 132.90545; m.p. 28.4℃; b.p. 669.3℃; sp. gr. 1.873 at 20℃; valence +1. Cesium is a ductil...radon
(Encyclopedia)radon rāˈdŏn [key], gaseous radioactive chemical element; symbol Rn; at. no. 86; mass no. of most stable isotope 222; m.p. about −71℃; b.p. −61.8℃; density 9.73 grams per liter at STP; vale...cobalt, chemical element
(Encyclopedia)cobalt, metallic chemical element; symbol Co; at. no. 27; at. wt. 58.9332; m.p. 1,495℃; b.p. about 2,870℃; sp. gr. 8.9 at 20℃; valence +2 or +3. Cobalt is a silver-white, lustrous, hard, brittle...neutrino astronomy
(Encyclopedia)neutrino astronomy, study of stars by means of their emission of neutrinos, fundamental particles that result from nuclear reactions and are emitted by stars along with light. Approximately 100 billio...nuclear energy
(Encyclopedia) CE5 Graph of binding energy per nucleon as a function of mass number nuclear energy, the energy stored in the nucleus of an atom and released through fission, fusion, or radioactivity. In these pr...Seaborg, Glenn Theodore
(Encyclopedia)Seaborg, Glenn Theodore sēˈbôrg [key], 1912–99, American chemist, b. Ishpeming, Mich., grad. Univ. of California at Los Angeles, 1934, Ph.D. Univ. of California at Berkeley, 1937. In 1939, he beg...nihonium
(Encyclopedia)nihonium nĭhōˈnēəm [key], artificially produced radioactive chemical element; symbol Nh; at. no. 113; mass number of most stable isotope 284; m.p., b.p., sp. gr., and valence unknown. Situated in...strontium
(Encyclopedia)strontium strŏnˈshēəm [key] [from Strontian, a Scottish town], a metallic chemical element; symbol Sr; at. no. 38; at. wt. 87.62; m.p. 769℃; b.p. 1,384℃; sp. gr. 2.6 at 20℃; valence +2. Stro...halogen
(Encyclopedia)halogen hălˈəjĕn [key] [Gr.,=salt-bearing], any of the chemically active elements found in Group 17 of the periodic table; the name applies especially to fluorine (symbol F), chlorine (Cl), bromin...molecular weight
(Encyclopedia)molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the ato...Browse by Subject
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