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tennessine

(Encyclopedia)tennessine tĕnˈəsēn [key], artificially produced radioactive chemical element; symbol Ts; at. no. 117; mass number of most stable isotope 294; m.p., b.p., sp. gr., and valence unknown. Tennessine ...

chemical bond

(Encyclopedia)chemical bond, mechanism whereby atoms combine to form molecules. There is a chemical bond between two atoms or groups of atoms when the forces acting between them are strong enough to lead to the for...

mercury, chemical element

(Encyclopedia)mercury or quicksilver [from the Roman god Mercury], metallic chemical element; symbol Hg [Lat. hydrargyrum=liquid silver]; at. no. 80; at. wt. 200.59; m.p. −38.842℃; b.p. 356.58℃; sp. gr. 13.55...

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...

berkelium

(Encyclopedia)berkelium bûrˈklēəm [key] [from Berkeley], artificially produced radioactive chemical element; symbol Bk; at. no. 97; mass no. of most stable isotope 247; m.p. about 1,050℃; b.p. about 2,590℃;...

promethium

(Encyclopedia)promethium prōmēˈthēəm [key], artificially produced radioactive chemical element; symbol Pm; at. no. 61; mass no. of most stable isotope 145; m.p. 1,042℃; b.p. 3,000℃ (estimated); sp. gr. unk...

Werner, Alfred

(Encyclopedia)Werner, Alfred, 1866–1919, French-born Swiss chemist, Ph.D. Univ. of Zürich, 1890. Werner was a professor at the Univ. of Zürich from 1893 until his death in 1919. He was awarded the Nobel Prize i...

stannic

(Encyclopedia)stannic: a chemical compound containing tin in the +4 valence state. ...

stannous

(Encyclopedia)stannous: a chemical compound containing tin in the +2 valence state. ...

Arrhenius, Svante August

(Encyclopedia)Arrhenius, Svante August sfänˈtə, ärāˈnēəs [key], 1859–1927, Swedish chemist. He was a professor of physics in Stockholm in 1895 and became director of the Nobel Institute for Physical Chemi...