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 |