Science Education Home Home Teachers Students Games Videos VA SOL Programs

It's Elemental

The Element Berkelium

[Click for Isotope Data]


97 Bk Berkelium 247

Atomic Number: 97

Atomic Weight: 247

Melting Point: 1323 K (1050°C or 1922°F)

Boiling Point: Unknown

Density: 14 grams per cubic centimeter

Phase at Room Temperature: Solid

Element Classification: Metal

Period Number: 7

Group Number: none

Group Name: Actinide

Special Notes: Radioactive and Artificially Produced

What's in a name? Named for the city of Berkeley, California.

Say what? Berkelium is pronounced as BURK-lee-em.

History and Uses:

Berkelium was first produced by Stanley G. Thompson, Glenn T. Seaborg, Kenneth Street, Jr. and Albert Ghiorso working at the University of California, Berkeley, in December, 1949. They bombarded an isotope of americium, americium-241, with alpha particles with a device called a cyclotron. This created berkelium-243 and two free neutrons.

Berkelium's most stable isotope, berkelium-247, has a half-life of about 1,380 years. It decays into americium-243 through alpha decay.

The first visible amounts of a berkelium compound, berkelium chloride (BkCl3) was produced in 1962 and weighed about 3 billionths of a gram (0.000000003 grams). Berkelium oxychloride (BkOCl), berkelium fluoride (BkF3), berkelium dioxide (BkO2) and berkelium trioxide (BkO3) have been identified and studied with a method known as X-ray diffraction.

Since only small amounts of berkelium have ever been produced, there are no known uses for berkelium and its compounds outside of basic scientific research.

Estimated Crustal Abundance: Not Applicable

Estimated Oceanic Abundance: Not Applicable

Number of Stable Isotopes: 0 (View all isotope data)

Ionization Energy: 6.23 eV

Oxidation States: +4, +3

Electron Shell Configuration:


2s2   2p6

3s2   3p6   3d10

4s2   4p6   4d10   4f14

5s2   5p6   5d10   5f9

6s2   6p6


Citation and linking information

For questions about this page, please contact Steve Gagnon.