Rhodium vs Promethium
| Property | Rh Rhodium | Pm Promethium |
|---|---|---|
| Atomic number | 45 | 61 |
| Symbol | Rh | Pm |
| Name | Rhodium | Promethium |
| Category | transition-metal | lanthanide |
| Standard Atomic Weight | 102.9055 u | 145 u |
| Period | 5 | 6 |
| Group | 9 | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Kr]5s14d8 | [Xe]6s24f5 |
| Oxidation states | [-3, -1, 1, 2, 3, 4, 5, 6, 7] | [2, 3] |
| Electronegativity (Pauling) | 2.28 | N/A |
| Electron affinity | 1.137 eV | 0.129 eV |
| Density | 1.240000e+4 kg/m³ | 7260 kg/m³ |
| Melting point | 1963.85 °C | 1041.85 °C |
| Boiling point | 3694.85 °C | 2999.85 °C |
| Discovery year | 1803 | 1902 |