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Author: Robert Husted, Mollie Boorman

Atomic Number 107
Atomic Symbol Bh
CAS ID No. 54037-14-8
Atomic Weight 262
Electron Configuration [Rn]7s2 5f14 6d5
Melting Point -
Boiling Point -
Density -

Formerly known as Ns, Nielsbohrium(1)

In 1976 Soviet scientists at Dubna announced they had synthesized element 107 by bombarding 204Bi with heavy nuclei of 54Cr. Reports say that experiments in 1975 had allowed scientists "to glimpse" the new element for 2/1000 s. A rapidly rotating cylinder, coated with a thin layer of bismuth metal, was used as a target. This was bombarded by a stream of 54Cr ions fired tangentially.

The existence of element 107 was confirmed by a team of West German physicists at the Heavy Ion Research Laboratory at Darmstadt, who created and identified six nuclei of element 107.

(1) The German discoverers at GSI proposed the name nielsbohrium (symbol Ns) after Niels Bohr. However, IUPAC changed that to bohrium (Bh).

Last Update: 2011-02-20