Berkelium

Element 97 on the periodic table, symbol Bk, group 3, period 7.

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.

Appearance: silvery

Properties

Atomic Number: 97
Atomic Mass: 247.0000 u
Group: 3
Period: 7
Block: f-block
Category: Actinide
State at 25 °C: Solid
Melting Point: 1,259 K · 985.9 °C
Boiling Point: 2,900 K · 2,626.9 °C
Density: 14.78 g/cm³
Atomic Radius: Not measured
Electronegativity: 1.3
Oxidation States: +3, +4
Abundance in Crust: Vanishingly rare
Discovered: 1949
Discovered By: Lawrence Berkeley National Laboratory

Electron Configuration

[Rn] 5f9 7s2

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f9

Ionisation Energies (kJ/mol)

1. 601

Elements near Berkelium

Elements in the same group share the number of outer electrons and behave in similar ways. Elements in the same period share a shell, so they change steadily from left to right.