Pm
Promethium
Element 61 · Lanthanide · Period 6, Group 7
Solid · Discovered 1945
Atomic Properties
| Atomic Number | 61 |
| Atomic Mass | 144.91276u |
| Electron Configuration | [Xe]6s2 4f5 |
| Atomic Radius | 236pm |
| Ionization Energy | 5.55eV |
| Oxidation States | +3 |
Physical Properties
| Standard State | Solid |
| Melting Point | 1315K |
| Boiling Point | 3273K |
| Density | 7.26g/cm³ |
| Group Block | Lanthanide |
| Year Discovered | 1945 |