The Columbia Encyclopedia. Copyright © 2001-09 Columbia University Press. All rights reserved.
- Periodic Table of the Elements: Americium
Periodic Table of the Elements: AmericiumAtomic Number:95Atomic Symbol:AmAmericiumAtomic Weight:(243)ElectronConfiguration:2 · 8 · 1832 · 258 · 2
- Am, chemical symbol
Am, symbol for the element americium.
- berkelium
Berkelium [from Berkeley], artificially produced radioactive chemical element; symbol Bk; at. no. 97; mass no. of most stable isotope 247; m.p. about 1,050°C; b.p. about 2,590°C; sp. gr. 14 (e...
- ununpentium
Ununpentium, artificially produced radioactive chemical element; symbol Uup; at. no. 115; mass number of most stable isotope 288; m.p., b.p., sp. gr., and valence unknown. Situated in Group 15...
- ununtrium
Ununtrium, artificially produced radioactive chemical element; symbol Uut; at. no. 113; mass number of most stable isotope 284; m.p., b.p., sp. gr., and valence unknown. Situated in Group 13 o...
- dubnium
Dubnium, artificially produced radioactive chemical element; symbol Db; at. no. 105; mass number of most stable isotope 262; m.p., b.p., and sp. gr. unknown; valence +5. Situated in Group 5 of...
- Seaborg, Glenn Theodore
Seaborg, Glenn Theodore, 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 began teaching...
- actinide series
Actinide series, a series of radioactive metallic elements in Group 3 of the periodic table. Members of the series are often called actinides, although actinium (at. no. 89) is not always cons...
- curium
Curium, artificially produced radioactive chemical element; symbol Cm; at. no. 96; mass no. of most stable isotope 247; m.p. about 1,340°C; b.p. 3,110°C; sp. gr. 13.5 (calculated); valence +3,...
- synthetic elements
Synthetic elements, in chemistry, radioactive elements that were not discovered occurring in nature but as artificially produced isotopes. They are technetium (at. no. 43), which was the first...
