Chromium (Cr)
Chromium
Chromium (Cr) is a transition metal in period 4, group 6. Its relative atomic mass is 51.996 and the molar mass of the atom is 51.996 g/mol.
Atomic number 24
Atomic mass 51.996
Molar mass 51.996 g/mol
Category Transition metal Solid
Properties of chromium
| Atomic number | 24 |
|---|---|
| Symbol | Cr |
| Latin name | Chromium |
| Relative atomic mass | 51.996 |
| Molar mass | 51.996 g/mol |
| Group, period, block | 6, 4, d |
| Category | Transition metal |
| State at 20 °C | Solid |
| Electron configuration | [Ar] 3d⁵ 4s¹ |
| Electronegativity (Pauling) | 1.66 |
| Atomic radius | 140 pm |
Electron configuration of chromium
Electrons per shell
K2L8M13N1
Full notation
1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹
Noble-gas notation
24 protons · 24 electrons[Ar] 3d⁵ 4s¹
Formula and compounds of chromium
Simple substanceCrchromiumMolar mass of Cr: 51.996 g/mol
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Frequently asked questions
The relative atomic mass of chromium is 51.996, so the molar mass of the atom is 51.996 g/mol.
Full: 1s² 2s² 2p⁶ 3s² 3p⁶ 3d⁵ 4s¹. Noble-gas notation: [Ar] 3d⁵ 4s¹.