Erbium

Symbol | Er
Latin name | Erbium
Atomic number | 68
Period | 6
Element category | Inner transition elements
Relative atomic mass | 167.26
Group | III.B
Electronegativity | 1.2
Oxidation numbers | 3
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f12 5d0 6s2
Density [g/cm3] | 9.066
State | Solid
Melting point [°C] | 1545
Boiling point [°C] | 2863
Atomic radius [pm] | 226
Thermal conductivity [W m-1K-1] | 14.3
Heat capacity [J K-1g-1] | 0.168
Discovery | 1843
Vickers hardness [MPa] | 589
Brinell hardness [MPa] | 814
Young's modulus [GPa] | 70
Electrical conductivity [S m-1] | 1.2 · 106
Shear modulus [GPa] | 28
1.st ionization energy [eV] | 6.1078
2.nd ionization energy [eV] | 11.929
3.rd ionization energy [eV] | 22.739
Stable isotopes | 6
Unstable isotopes | 10