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n. A synthetic transuranic radioactive element having 9 isotopes with mass numbers from 243 to 250 and half-lives from 3 hours to 1,380 years. Atomic number 97; melting point 986°C; valence 3, 4. See Table at element.

n. A transuranic chemical element (symbol Bk) with an atomic number of 97.

n. a chemical element of the transuranic series. Chemical symbol Bk; atomic number 97; atomic weight 247. It is a radioactive element, with no stable isotopes; the longest-lived isotope is of mass number 247.07, decaying by alpha-emission with a half-life of 1,400 years. The isotope with atomic weight 249 has a half-life of 314 days, and was isolated in weighable quantities.

n. a radioactive transuranic element; discovered by bombarding americium with helium

"The team produced six atoms of the element by smashing together isotopes of calcium and a radioactive element called berkelium in a particle accelerator about 75 miles north of Moscow on the Volga River, according to a paper that has been accepted for publication at the journal Physical Review Letters."

metallic element    metal   

Berkeley   

berkelium trioxide    berkelium dioxide    berkelium oxychloride    berkelium chloride    berkelium fluoride   

Bk