Cobalt

Symbol | Co
Latin name | Cobaltum
Atomic number | 27
Period | 4
Element category | Transition elements
Relative atomic mass | 58.93320
Group | VIII.B
Electronegativity | 1.8
Oxidation numbers | 2, 3
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d7 4s2
Density [g/cm3] | 8.9
State | Solid
Melting point [°C] | 1494
Boiling point [°C] | 2900
Atomic radius [pm] | 152
Covalent radius [pm] | 126
Thermal conductivity [W m-1K-1] | 100
Heat capacity [J K-1g-1] | 0.421
Discovery | 1735
Hardness [Mohs scale] | 5.5
Vickers hardness [MPa] | 1043
Brinell hardness [MPa] | 700
Young's modulus [GPa] | 209
Electrical conductivity [S m-1] | 1.7 · 107
Shear modulus [GPa] | 75
1.st ionization energy [eV] | 7.881
2.nd ionization energy [eV] | 17.06
3.rd ionization energy [eV] | 33.5
Stable isotopes | 1
Unstable isotopes | 13