Chemical data for Ir - Iridium | PhysLink.com

Iridium

 Iridium 
Ir
Atomic Number: 77
Atomic Weight: 192.217
Element Type: Transition Metal
Crystal Structure: Cubic Face Centered
Melting Point: 2446.0°C = 4434.8°F = 2719.15 K
Boiling Point: 4428.0°C = 8002.4°F = 4701.15 K
Critical Temp: °C = °F = K
Atomic Radius: 1.87 Å (Å = Angstrom = 10-10 m)
Covalent Radius: 1.27 Å
Electronegativity: 2.2

History

(L. iris, rainbow) Tennant discovered iridium in 1803 in the residue left when crudeplatinum is dissolved by aqua regia. The name iridium is appropriate because itssalts are highly colored.


Sources

Iridium occurs uncombined in nature with platinum and other metals of this family inalluvial deposits. It is recovered as a by-product from the nickel mining industry.