Discovered By: George Brandt
Discovery year: 1735

The following table showing some properties of Cobalt(Co):

Table Example
Atomic number 27
Group 9
Period 4
Block d
Electrons 27
Protons 27
Neutrons 32
Atomic weight 58.933194
Oxidation states -1, +2, +3
Ionic charge Co^2+, Co^3+


Table Example
Electrons per shell K2 L8 M15 N2
Electron configuration 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^7
Atomic radius 152 pm
Covalent radius 126 pm
Boiling point 2927°C
Melting point 1495°C
Phase Solid
Fusion heat 16.2 kJ.mol^-1
Thermal expansion 1.3*10^-5 K^-1
Vaporization heat 375 kJ.mol^-1


Table Example
Color Gray
Bulk modulus 180 GPa
Brinell hardness 700 MPa
Density 8900 kg.m^-3
Liquid density 7750 kg.m^-3
Mohs hardness 5
Molar volume 6.6*10^-6 m^3.mol^-1
Poisson ratio 0.31
Shear modulus 75 GPa
Sound speed 4720 m.s^-1


Table Example
Thermal conductivity 100 W.m^-1.K^-1
Vickers hardness 1043 MPa
Young's modulus 209 GPa
Electric type Conductor
Magnetic type Ferromagnetic
Resistivity 6*10^-8 Ohm.m
Curie point 1394 K
Electronegativity 1.88
Valence 4
Radioactive No
Neutron cross section 37.2 barn