ELEMENTLE

Element 107 · Transition Metal

Bohrium

Period 7 · Group 7

Bohrium is a chemical element with symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 270Bh, has a half-life of approximately 61 seconds.

Three reasons Bohrium stands out

  1. 1

    Named after famous Danish physicist who contributed to the foundations of atomic structure.

  2. 2

    Its most stable known isotope has a half-life of only about 61 seconds.

  3. 3

    Only a few dozen atoms of it have ever been synthesised, making direct observation nearly impossible.

Testing group seven one atom at a time

Bohrium honors Niels Bohr, whose atomic model helped make sense of periodic behavior. Its atoms are produced in heavy-ion collisions and usually decay within seconds. Chemists have nevertheless formed a volatile bohrium compound, finding behavior consistent with heavier-member status beneath rhenium.

Bohrium at a glance
Atomic number / protons107
SymbolBh
Family (Elementle)Transition Metal
Classification (PubChem)Transition metal
Period7
Group7
Atomic mass (u)270.133
Standard stateBulk state not experimentally established
Electron configuration[Rn]7s2 5f14 6d5
Reported oxidation states7, 5, 4, 3
Electronegativity (Pauling)Not available
Atomic radius (pm)Not available
First ionization energy (eV)Not available
Electron affinity (eV)Not available
Density (g/cm³)Not available
Melting pointNot available
Boiling pointNot available
Discovery (PubChem)1976

Values are reference data, not a specification for every temperature, pressure, or allotrope. Unknown properties are left unavailable. Superheavy-element predictions remain uncertain.

Sources & further reading

PubChem: Bohrium · Bohrium on Wikipedia

The introduction and original editorial story are adapted from Wikipedia contributors via Periodic-Table-JSON. Element descriptions and their adaptations are available under CC BY-SA 3.0. Numerical attributes use the PubChem periodic-table dataset, retrieved September 22, 2026.