NO. 027Transition

Co

Cobalt

Cobalt is a hard, magnetic metal used in batteries, superalloys, and blue pigments for glass and ceramics.

Crystal Structure

Hexagonal close-packed (hcp)

Atomic Mass58.93 u

Density8.9 g/cm³

Melting Point1768 K

Boiling Point3200 K

Atomic Radius125 pm

Electronegativity1.88

Ionization Energy760 kJ/mol

Electron Affinity63 kJ/mol

Bonding TypeMetallic

Oxidation States2, 3

Acid/BaseBasic

ReactivityLow

Electron Configuration

[Ar] 3d7 4s2

Discovered ByGeorg Brandt

Year1735

Known Isotopes

Co-59