Iridium (Ir): electron configuration, atomic mass and facts
Iridium (Ir) is element 77 of the periodic table, a transition metal in period 6, group 9. Its electron configuration is [Xe] 4f14 5d7 6s2, with electrons arranged in shells 2, 8, 18, 32, 15, 2, and its standard atomic weight is 192.22 u.
▶ Watch Iridium’s electrons orbit in the interactive periodic tableIridium at a glance
| Symbol | Ir |
|---|---|
| Atomic number | 77 |
| Atomic mass | 192.22 u |
| Category | Transition metal |
| Group | 9 |
| Period | 6 |
| Block | d-block |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d7 6s2 |
| Noble-gas shorthand | [Xe] 4f14 5d7 6s2 |
| Electrons per shell | 2, 8, 18, 32, 15, 2 |
| Electronegativity (Pauling) | 2.2 |
| State at 20 °C | solid |
Where is Iridium on the periodic table?
Iridium is in period 6, group 9, in the d-block. The period number matches its 6 electron shells, and the block names the subshell its last electrons fill. In the same group, Rhodium sits directly above it and Meitnerium sits directly below it. Elements in the same column of the d-block often have similar chemistry.
How to work out the electron configuration of Iridium
Put 77 electrons into subshells in order of rising energy, filling each before starting the next: 1s² (2), 2s² (4), 2p⁶ (10), 3s² (12), 3p⁶ (18), 4s² (20), 3d¹⁰ (30), 4p⁶ (36), 5s² (38), 4d¹⁰ (48), 5p⁶ (54), 6s² (56), 4f¹⁴ (70), 5d⁷ (77). In shorthand, [Xe] stands for the 54 electrons of xenon, giving [Xe] 4f¹⁴ 5d⁷ 6s².
How electronegative is Iridium?
Iridium has a Pauling electronegativity of 2.2, ranking 17 of the 100 elements with a known value (fluorine is highest at 3.98). That is in the middle of the range.
Frequently asked questions
What is the electron configuration of Iridium?
The electron configuration of Iridium (Ir) is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d7 6s2. In noble-gas shorthand it is written [Xe] 4f14 5d7 6s2.
How many electrons does Iridium have in each shell?
Iridium has 77 electrons arranged in shells as 2, 8, 18, 32, 15, 2.
What is the atomic mass of Iridium?
The standard atomic weight of Iridium is 192.22 u, so one mole of Iridium atoms has a mass of about 192.22 g.
Is Iridium a metal?
Yes. Iridium is a transition metal.
Explore nearby elements
More transition metals: Tungsten, Rhenium, Osmium, Platinum, Gold, Mercury. See all elements on the periodic table.