Neodymium vs Promethium
| Property | Nd Neodymium | Pm Promethium |
|---|---|---|
| Atomic number | 60 | 61 |
| Symbol | Nd | Pm |
| Name | Neodymium | Promethium |
| Category | lanthanide | lanthanide |
| Standard Atomic Weight | 144.242 u | 145 u |
| Period | 6 | 6 |
| Group | N/A | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Xe]6s24f4 | [Xe]6s24f5 |
| Oxidation states | [0, 2, 3, 4] | [2, 3] |
| Electronegativity (Pauling) | 1.14 | N/A |
| Electron affinity | 1.913 eV | 0.129 eV |
| Density | 7010 kg/m³ | 7260 kg/m³ |
| Melting point | 1020.85 °C | 1041.85 °C |
| Boiling point | 3073.85 °C | 2999.85 °C |
| Discovery year | 1841 | 1902 |