Iridium (Ir) - Element 77 | Properties & Electron Configuration
What is Iridium?
Iridium (Ir) is element 77, a transition metal in period 6, group 9. Its electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d⁷ 6s².
| Atomic Number | 77 |
| Symbol | Ir |
| Atomic Mass | 192.22 u |
| Category | Transition Metal |
| Period | 6 |
| Group | 9 |
| Block | d |
| Electron Configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d⁷ 6s² |
| Short Config | [Xe] 4f¹⁴ 5d⁷ 6s² |
| Electronegativity | 2.2 |
| Atomic Radius | 135 pm |
| Ionization Energy | 880 kJ/mol |
| Electron Affinity | 151 kJ/mol |
| Phase (STP) | Solid |
Electron Configuration
The full electron configuration of Iridium is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d⁷ 6s². In noble gas shorthand, this is written as [Xe] 4f¹⁴ 5d⁷ 6s².
Iridium is a d-block element in group 9, period 6.
Periodic Trends
Electronegativity: Iridium has a Pauling electronegativity of 2.2. Within group 9, electronegativity generally decreases down the group.
Atomic Radius: 135 pm. Across period 6, atomic radius generally decreases left to right as nuclear charge increases.
Ionization Energy: 880 kJ/mol. Ionization energy generally increases across a period and decreases down a group.
View all 118 elements with trend overlays for electronegativity, atomic radius, ionization energy, and electron affinity.
Explore Iridium on the Interactive Periodic TableRelated Topics
Cobalt (Co)
Properties of Cobalt - same group as Iridium
Rhodium (Rh)
Properties of Rhodium - same group as Iridium
Meitnerium (Mt)
Properties of Meitnerium - same group as Iridium
Cesium (Cs)
Properties of Cesium - same period as Iridium
Barium (Ba)
Properties of Barium - same period as Iridium
Lanthanum (La)
Properties of Lanthanum - same period as Iridium