Ruthenium vs Erbium
| Property | Ru Ruthenium | Er Erbium |
|---|---|---|
| Atomic number | 44 | 68 |
| Symbol | Ru | Er |
| Name | Ruthenium | Erbium |
| Category | transition-metal | lanthanide |
| Standard Atomic Weight | 101.07 u | 167.259 u |
| Period | 5 | 6 |
| Group | 8 | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Kr]5s14d7 | [Xe]6s24f12 |
| Oxidation states | [-4, -2, 1, 2, 3, 4, 5, 6, 7, 8] | [0, 1, 2, 3] |
| Electronegativity (Pauling) | 2.2 | 1.24 |
| Electron affinity | 1.05 eV | 0.312 eV |
| Density | 1.210000e+4 kg/m³ | 9070 kg/m³ |
| Melting point | 2333.85 °C | 1528.85 °C |
| Boiling point | 4149.85 °C | 2867.85 °C |
| Discovery year | 1828 | 1843 |