Chromium

Symbol: Cr
Atomic number: 24
Category: transition metals
Group: 6
Period: 4
Block: d
Atomic weight: 51.9961 g/mol
Electrons per shell: 2, 8, 13, 1
CAS number: 7440-47-3
Phase: solid
Density: 7.19 kg/dm3 (near room temperature)
Melting point: 2180 K (1857 °C, 3465 °F)
Boiling point: 2944 K (2672 °C, 4840 °F)
Crystal structure: cubic body centered
Oxidation states: 6, 5, 4, 3, 2, 1
Electronegativity: 1.66 (Pauling scale)
Name's origin: chroma
Name's meaning: the Greek word meaning color, because of the many colorful compounds made from it
Facts:
- is notable for its ability to form quintuple covalent bonds
- is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point
- the most notable use is in metallurgy (plating and as alloy constituent)
- the 6+ compounds are carcinogenic