Cr - Chromium

Chromium

 Chromium 
Cr
Atomic Number: 24
Atomic Weight: 51.9961
Element Type: Transition Metal
Crystal Structure: Cubic Body Centered
Melting Point: 1907.0°C = 3464.6°F = 2180.15 K
Boiling Point: 2671.0°C = 4839.8°F = 2944.15 K
Critical Temp: °C = °F = K
Atomic Radius: 1.85 Å (Å = Angstrom = 10-10 m)
Covalent Radius: 1.18 Å
Electronegativity: 1.66

History

(Gr. chroma, color) Discovered in 1797 by Vauquelin, who prepared the metal the nextyear, chromium is a steel-gray, lustrous, hard metal that takes a high polish.


Sources

The principal ore is chromite, which is found in Zimbabwe, Russia, Transvaal, Turkey,Iran, Albania, Finland, Democratic Republic of Madagascar, and the Phillippines. The metalis usually produced by reducing the oxide with aluminium.