← Back to the periodic table
61
Pm
[145]
Promethium
Lanthanides · Group 7 · Period 6–7 (f)
Atomic properties
| Atomic number | 61 |
|---|---|
| Symbol | Pm |
| Standard atomic weight | [145] |
| Classification | Lanthanides |
| Group | f-block series |
| Period | 6 |
| Block | f-block (lanthanide) |
| Electron configuration | [Xe] 4f5 6s2 |
| Electronegativity (Pauling) | 1.13 |
| Common oxidation states | +3 |
Physical properties
| Phase at 20 °C | Solid |
|---|---|
| Density | 7.26 g/cm³ |
| Melting point | 1042 °C |
| Boiling point | 3000 °C |
| Discovered | 1945 |
| CAS number | — |