NO. 105Transition

Db

Dubnium

Dubnium is a synthetic Transition whose chemical behavior resembles tantalum and niobium.

Crystal Structure

Hexagonal close-packed (predicted)

Atomic Mass268 u

Density18 g/cm³

Melting Point2200 K

Boiling Point5500 K

Atomic Radius149 pm

Electronegativity1.3

Ionization Energy585 kJ/mol

Electron Affinity0 kJ/mol

Bonding TypeMetallic

Oxidation States5

Acid/BaseBasic

ReactivityMedium

Electron Configuration

[Rn] 5f14 6d3 7s2

Discovered ByJoint Institute for Nuclear Research

Year1967

Known Isotopes

Db-268