Rhodium vs Iridium
| Property | Rh Rhodium | Ir Iridium |
|---|---|---|
| Atomic number | 45 | 77 |
| Symbol | Rh | Ir |
| Name | Rhodium | Iridium |
| Category | transition-metal | transition-metal |
| Standard Atomic Weight | 102.9055 u | 192.217 u |
| Period | 5 | 6 |
| Group | 9 | 9 |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Kr]5s14d8 | [Xe]6s24f145d7 |
| Oxidation states | [-3, -1, 1, 2, 3, 4, 5, 6, 7] | [-3, -2, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9] |
| Electronegativity (Pauling) | 2.28 | 2.2 |
| Electron affinity | 1.137 eV | 1.565 eV |
| Density | 1.240000e+4 kg/m³ | 2.256220e+4 kg/m³ |
| Melting point | 1963.85 °C | 2445.85 °C |
| Boiling point | 3694.85 °C | 4427.85 °C |
| Discovery year | 1803 | 1803 |