77
Ir
192.22
Iridium (Ir)
Element 77 · Period 6 · Group 9
transition-metal
solid at room temp
d-block
About Iridium
Second densest element. Most corrosion-resistant metal. The KT boundary iridium anomaly suggests a meteorite impact.
Physical Properties
Atomic Mass
192.22 u
State at 25°C
Solid
Melting Point
2446 °C
Boiling Point
4428 °C
Density
22.56 g/cm³
Magnetism
Paramagnetic
Atomic Properties
Electron Configuration
[Xe] 4f¹⁴ 5d⁷ 6s²
Electron Shells
2, 8, 18, 32, 15, 2
Electronegativity
2.2
Atomic Radius
180 pm
Ionization Energy
880 kJ/mol
Oxidation States
+3, +4
Discovery & History
Discovered By
Smithson Tennant
Discovery Year
1803
Named By
Smithson Tennant
Name origin: Latin: iris (rainbow)
Frequently Asked Questions
- Is Iridium a metal, nonmetal, or metalloid?
- Iridium is classified as a transition-metal.
- What state is Iridium in at room temperature?
- Iridium is a solid at standard room temperature (25°C).
- What is the atomic mass of Iridium?
- Iridium has an atomic mass of 192.22 atomic mass units (u).
- Who discovered Iridium?
- Iridium was discovered by Smithson Tennant in 1803.
- Where is Iridium on the periodic table?
- Iridium is element number 77, located in period 6 and group 9.