Periodic Table of Elements




Bohrium was discovered by Peter Armbruster and Gottfried Munzenberg at Darmstadt, Germany in 1981.

Name: Bohrium
Symbol: Bh
Atomic number: 107
Atomic weight: 270
State: solid presumably
Group, period, block: 7, 7, d
Color: unknown
Classification: transition metal
Electron configuration: 5f14 6d5 7s2

Physical properties

Density: 37 g/cm-3
Melting point: no data
Boiling point: no data

Atomic properties

Oxidation states: 7, 5, 4, 3
Electronegativity: no data
Ionization energies: 1st: 742.9 kJ·mol-1
Covalent radius: 141 pm
Van der Waals radius: no data
  • Bh
  • Electron Configuration


Bohrium is an artificial element, and thus a standard atomic mass cannot be given. Like all artificial elements, it has no stable isotopes. The first isotope to be synthesized was 262Bh in 1981. There are 11 known isotopes ranging from 260Bh to 274Bh, and 1 isomer, 262mBh. The longest-lived isotope is 270Bh with a half-life of 1 minute.