Thorium

Symbol | Th
Latin name | Thorium
Atomic number | 90
Period | 7
Element category | Inner transition elements
Relative atomic mass | 232.0381
Group | IV.B
Electronegativity | 1.3
Oxidation numbers | 4
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f0 6d2 7s2
Density [g/cm3] | 11.72
State | Solid
Melting point [°C] | 1750
Boiling point [°C] | 4500
Thermal conductivity [W m-1K-1] | 54
Heat capacity [J K-1g-1] | 0.113
Discovery | 1828
Hardness [Mohs scale] | 3
Vickers hardness [MPa] | 350
Brinell hardness [MPa] | 400
Young's modulus [GPa] | 79
Electrical conductivity [S m-1] | 6.7 · 106
Shear modulus [GPa] | 31
1.st ionization energy [eV] | 6.08
2.nd ionization energy [eV] | 11.504
3.rd ionization energy [eV] | 20.003
Stable isotopes | 0
Unstable isotopes | 12