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polonium
(Encyclopedia)polonium pəlōˈnēəm [key], radioactive chemical element; symbol Po; at. no. 84; mass no. of most stable isotope 209; m.p. 254℃; b.p. 962℃; sp. gr. about 9.4; valence +2 or +4. Polonium is an e...Po, chemical symbol
(Encyclopedia)Po, symbol for the element polonium. ...Periodic Table of the Elements: Polonium
(Encyclopedia)Periodic Table of the Elements: Polonium ...livermorium
(Encyclopedia)livermorium, artificially produced radioactive chemical element; symbol Lv; at. no. 116; mass number of most stable isotope 292; m.p., b.p., sp. gr., and valence unknown. Situated in Group 16 of the p...pitchblende
(Encyclopedia)pitchblende pĭchˈblĕndˌ [key], dark, lustrous, heavy mineral, a source of radium and uranium. Largely natural uranium oxides, triuranium octaoxide (U3O8) and uranium dioxide (UO2), it usually cont...Curie
(Encyclopedia)Curie kürēˈ [key], family of French scientists. Pierre Curie, 1859–1906, scientist, and his wife, Marie Sklodowska Curie, 1867–1934, chemist and physicist, b. Warsaw, are known for their work o...Arafat, Yasir
(Encyclopedia)Arafat, Yasir or Yasser yäsērˈ ärˈäfät; –sər [key], 1929–2004, leader of the Palestine Liberation Organization (PLO), the coordinating body for Palestinian organizations, and head of Al Fa...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...Elements (table)
(Encyclopedia)Elements 1 Parentheses indicate most stable isotope; brackets enclose lower and upper bounds of weight variation. ...Browse by Subject
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