Berkelium

Actinide · atomic number 97

97247BkBerkeliumSolidActinide

Berkelium is a transuranic radioactive chemical element with symbol Bk and atomic number 97. It is a member of the actinide and transuranium element series. It is named after the city of Berkeley, California, the location of the University of California Radiation Laboratory where it was discovered in December 1949.

Properties of Berkelium

Element category	Actinide
Atomic number	97
Atomic mass	247 u
Phase at STP	Solid
Group	3
Period	7
Block	f
Electron configuration	[Rn] 5f9 7s2
Electrons per shell	2, 8, 18, 32, 27, 8, 2
Electronegativity (Pauling)	1.3
Melting point	1259 K (986 °C)
Boiling point	2900 K (2627 °C)
Density	14.78 g/cm3
Discovered by	Lawrence Berkeley National Laboratory

← Curium · Periodic table · Californium → Cf

About the actinide group

Mostly radioactive, heavy metals — several made only in reactors — whose fission powers nuclear energy and weapons.

Data: Periodic-Table-JSON (CC BY-SA 3.0) · stored statically on our server. https://en.wikipedia.org/wiki/Berkelium

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