Cr
Chromium51.9961 (6)
Chromium was discovered by Louis-Nicholas Vauquelin at 1797 in France. Origin of name: from the Greek word "chroma" meaning "colour", named for the many coloured compounds known for chromium. This was eventually identified as chromium oxide. Chromium oxide was discovered in 1797 by Louis-Nicholas Vauquelin, who prepared the metal itself in the following year.
- Name: Chromium
- Symbol: Cr
- Atomic number: 23
- Atomic weight:51.9961 (6)
- Standard state: solid at 298 K
- Group in periodic table: 6
- Group name:none
- Period in periodic table: 4
- Block in periodic table: d-block
- Classification: Metallic
- wide use as a catalyst
- tanning leather
- lead chromate as chrome yellow is a pigment
Emerald is a form of beryl (a beryllium aluminium silicate) which is green because of the inclusion of a little chromium into the beryl crytal lattice in place of some of the aluminium ions.