← Back to the periodic table
77
Ir
192.22
Iridium
Transition metals · Group 9 · Period 6
Atomic properties
| Atomic number | 77 |
|---|---|
| Symbol | Ir |
| Standard atomic weight | 192.22 |
| Classification | Transition metals |
| Group | 9 |
| Period | 6 |
| Block | d-block |
| Electron configuration | [Xe] 4f14 5d7 6s2 |
| Electronegativity (Pauling) | 2.20 |
| Common oxidation states | +4, +3 |
Physical properties
| Phase at 20 °C | Solid |
|---|---|
| Density | 22.56 g/cm³ |
| Melting point | 2466 °C |
| Boiling point | 4428 °C |
| Discovered | 1803 |
| CAS number | — |