Promethium |
| Symbol | Pm |
|---|---|
| Latin name | Promethium |
| Atomic number | 61 |
| Period | 6 |
| Element category | Inner transition elements |
| Relative atomic mass | 146.9151 |
| Group | III.B |
| Electronegativity | 1.2 |
| Oxidation numbers | 3 |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f5 5d0 6s2 |
| Density [g/cm3] | 7.23 |
| State | Solid |
| Melting point [°C] | 1168 |
| Boiling point [°C] | 2460 |
| Atomic radius [pm] | 205 |
| Thermal conductivity [W m-1K-1] | 17.9 |
| Discovery | 1945 |
| Young's modulus [GPa] | 46 |
| Electrical conductivity [S m-1] | 1.3 · 106 |
| Shear modulus [GPa] | 18 |
| 1.st ionization energy [eV] | 5.55 |
| 2.nd ionization energy [eV] | 10.903 |
| 3.rd ionization energy [eV] | 22.283 |
| Stable isotopes | 0 |
| Unstable isotopes | 14 |