A silver-gray, lustrous, brittle, hard metallic → chemical element
that is resistant to tarnish and corrosion; symbol Cr.
→ Atomic number 24;
→ atomic weight 51.996;
→ melting point about 1,857°C;
→ boiling point about 2,672°C;
→ specific gravity about 7.2 at 20°C.
Chromium is used in the hardening of steel alloys and the production of stainless steels.
It is extracted by reducing the oxide with → aluminium.
Its → radioactive isotope 51Cr has a half-life
of 27.8 days. It was discovered in 1797 by the French chemist and pharmacist
Nicolas-Louis Vauquelin (1763-1829).
See also: From the Gk. chroma “color,” from the many colored compounds of this element,
- -ium a suffix used in the name of several chemical elements.