Periodic Table of Elements

77

Iridium

192.22

Iridium was discovered by Smithson Tennant in London, England in 1803.

Name: Iridium
Symbol: Ir
Atomic number: 77
Atomic weight: 192.22
State: solid
Group, period, block: 9, 6, d
Color: silvery white
Classification: transition metal
Electron configuration: 4f14 5d7 6s2
2,8,18,32,15,2

Physical properties

Density: 22.56 g/cm-3
Melting point: 2739 K, 2466 C, 4471 F
Boiling point: 4701 K, 4428 C, 8002 F

Atomic properties

Oxidation states: 3, -1, 0, 1, 2, 3, 4, 5, 6
Electronegativity: 2.20 (Pauling scale)
Ionization energies: 1st: 880 kJmol-1
Covalent radius: 1416 pm
Van der Waals radius: no data
  • Ir
  • Electron Configuration

Isotopes

There are two naturally occurring isotopes of iridium exist, 191Ir, and 193Ir.