In detail

Chromium (Cr) properties


Atomic mass, symbol and atomic number

chrome is a naturally occurring element with the element symbol Cr and atomic number 24. In the periodic table it stands with an atomic mass of 51.996 u in the 6th subgroup. The chemical element discovered by Louis Vauquelin in 1797 is not radioactive and is in a solid state at room temperature.

Profile: Chrome (Chromium)

General
Chemical element:chrome
Symbol:Cr
Atomic number:24
Group:Chrome group
Period:4
Block:d-block
Series:Transition metals
Appearance:silver
explorers:Louis-Nicolas Vauquelin
Year of discovery:1797
Atomic properties
Atomic mass:51,996 u
Atomic radius:140 pm
Covalent radius:139 pm
Van der Waals radius:unknown
Electron configuration:Ar 3d5 4s1
ionization:652.9 kJ / mol
Physical Properties
Physical state:firmly
Density:7.14 g / cm3
Crystal structure:cubic
Magnetism:paramagnetic
molar volume:7,23 · 10-6 m3/ mol
Mohs hardness:8,5
Melting point:1907 ° C
Boiling point:2482 ° C
Heat of fusion:16.9 kJ / mol
Heat of vaporization:347 kJ / mol
Thermal conductivity:94 W
Chemical properties
electronegativity:1,66

Did you know that ...

  • Chromium is often part of alloys to prevent corrosion (rust) on metals?
  • Chromium oxides were formerly used as dyes (especially yellow and green)?
  • Chrome with a Mohs hardness of 8.5 is one of the hardest elements?