Periodic table / Transition metals
24Chromium
Chromium is a transition metal in group 6, period 4. At 25 °C it is a solid.
- Symbol
- Cr
- Atomic number
- 24 protons in the nucleus
- Standard atomic weight
- 51.996 ± 0.001
- Electron configuration
- [Ar] 3d5 4s1
- Electrons in each shell
- 2, 8, 13, 1
- Group, period, block
- 6, 4, d
- Family
- Transition metals
- State at 25 °C
- solid
- Electronegativity
- 1.66 (Pauling scale)
- First ionisation energy
- 652.9 kJ/mol (6.76651 eV)
Read about it
Where these numbers come from
Atomic weight: IUPAC CIAAW, abridged standard atomic weights 2024. Electron configuration and ionisation energy: NIST Atomic Spectra Database. Family, state and electronegativity: PubChem. See Sources. Melting points, boiling points and densities are left out for now: published values differ between sources, and we will add them once each has been checked.