Iridium
Transition Metal
Iridium (Ir) is a chemical element with atomic number 77, classified as a transition metal. At room temperature it is a solid. It was discovered in 1803 by Smithson Tennant.
Properties
- Atomic number
- 77
- Atomic mass
- 192.22 u
- Category
- Transition Metal
- Group
- 9
- Period
- 6
- Block
- d-block
- Electron configuration
- [Xe] 4f¹⁴ 5d⁷ 6s²
- Phase at STP
- Solid
- Density
- 22.56 g/cm³
- Melting point
- 2719 K (2445.8 °C)
- Boiling point
- 4701 K (4427.9 °C)
- Electronegativity
- 2.2
- Atomic radius
- 180 pm
- Ionization energy
- 8.967 eV
- Discovery
- 1803 · Smithson Tennant
Common uses
Spark plugs, crucibles, jewelry, anticancer drugs
Did you know?
Most corrosion-resistant element and linked to dinosaur extinction.
Experiment with the elements
Iridium doesn't form any compounds in our lab yet, but the periodic table sandbox lets you combine dozens of other real elements into real compounds — water, table salt, ammonia and many more — with their true chemical formulas.