Dubnium

Atomic number

105

Atomic mass (u)

268.126

Category

Transition metal

Standard state

Solid

Melting point

Not reported

Boiling point

Not reported

Density (g/cm³)

Not reported in this source

Electronegativity (Pauling)

Not reported in this source

Electron configuration

[Rn]7s2 5f14 6d3

Oxidation states

5, 4, 3

Atomic radius (pm)

Not reported in this source

First ionization energy (eV)

Not reported in this source

Discovery & recognition

Discovery year / period (PubChem)

1967

Discovery credited to (RSC)

Scientists at both Berkeley, California, USA, and Dubna, near Moscow, Russia

Date or period recorded by RSC

1968-1970

Discovery place

Dubna, Russia, and Berkeley, United States; disputed priority

An ancient date does not identify a first human discovery. Different references may date observation, isolation and formal recognition differently.

Natural occurrence & production

This transuranium element is primarily produced through nuclear reactions in reactors or particle accelerators. Some transuranium elements also occur naturally in extremely small traces; that is different from a mineable deposit.

“Dubnium does not occur naturally. It is a transuranium element created by bombarding californium-249 with nitrogen-15 nuclei.”

Royal Society of Chemistry · occurrence excerpt ↗

Continue the research

Reference values are not product specifications. Blank values have not been estimated. For superheavy elements, some properties and family assignments are theoretical or incompletely measured.