Nickel vs Promethium
| Property | Ni Nickel | Pm Promethium |
|---|---|---|
| Atomic number | 28 | 61 |
| Symbol | Ni | Pm |
| Name | Nickel | Promethium |
| Category | transition-metal | lanthanide |
| Standard Atomic Weight | 58.6934 u | 145 u |
| Period | 4 | 6 |
| Group | 10 | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Ar]4s23d8 | [Xe]6s24f5 |
| Oxidation states | [-2, -1, 0, 1, 2, 3, 4] | [2, 3] |
| Electronegativity (Pauling) | 1.91 | N/A |
| Electron affinity | 1.156 eV | 0.129 eV |
| Density | 8912 kg/m³ | 7260 kg/m³ |
| Melting point | 1454.85 °C | 1041.85 °C |
| Boiling point | 2912.85 °C | 2999.85 °C |
| Discovery year | 1751 | 1902 |