The Periodic Table of Elements
61
Pm
Promethium
[ 145 ] amu
Additional Information:
| State | Group Block | Density | Atomic Radius | Electron Affinity | Ionization Energy | Melting Point | Boiling Point | Year Discovered |
|---|---|---|---|---|---|---|---|---|
| solid | lanthanoid | 7.264 kg/L | pm | -50 | 540 kJ/mol | 1373 °K | 3273 °K | 1947 |
