About

Berkelium is a synthetic radioactive element named after Berkeley, California, the home of the University of California lab where it was discovered. It is produced in minute, milligram quantities in specialized nuclear reactors. Due to its rarity and short half-life, it is used almost exclusively for scientific research, particularly for bombarding with other particles to synthesize even heavier elements like tennessine.

Atomic Properties

Atomic Number97

Atomic Weight247 u

Neutrons (common)150

Electron Configuration[Rn] 5f⁹ 7s²

Full Configuration1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁶ 5f⁹ 7s²

Electrons per Shell2, 8, 18, 32, 27, 8, 2

Electronegativity1.3

Oxidation States+3, +4

Ionic Radius96 pm

Periodic Table Position

Group3

Period7

BlockF

Chemical SeriesActinoids

Physical Properties

State at STPsolid

Appearancesilvery-white metallic

Crystal Structurehcp

Magnetic Orderingparamagnetic

Thermal Properties

Melting Point1,259 K

Boiling Point2,900 K

Thermal Conductivity10 W/(m·K)

Specific Heat0.11 J/(g·K)

Heat of Fusion7.92 kJ/mol

Discovery

Discovered byGlenn T. Seaborg, Stanley G. Thompson, Albert Ghiorso, Eugene K. Hulet

Discovery Year1,949

Occurrencesynthetic

CAS Number7440-40-6

Electron Configuration

Energy

↿⇂

1s

↿⇂

2s

↿⇂

2p

↿⇂

3s

↿⇂

3p

↿⇂

4s

↿⇂

3d

↿⇂

4p

↿⇂

5s

↿⇂

4d

↿⇂

5p

↿⇂

6s

↿⇂

4f

↿⇂

5d

↿⇂

6p

↿⇂

7s

↿⇂

↿

5f

6d

7p

Isotopes of Berkelium

Symbol ▲	Mass (u) ▲	Abundance ▲	Half-life ▲	Decay Mode ▲
²⁴⁷Bk	247.070300	—	1.38 ky	Alpha Decay