27 Co 58.933
Cobalt
transition metal
Properties
- Atomic number
- 27
- Atomic mass
- 58.933 u
- Category
- transition metal
- Group
- 9
- Period
- 4
- Block
- d-block
- State (room temp)
- Solid
- Outer-shell electrons
- 2
- Electronegativity
- 1.88 (Pauling)
- Density
- 8.9 g/cm³
- Melting point
- 1494.85 °C
- Boiling point
- 2926.85 °C
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d⁷
Noble-gas shorthand: [Ar] 3d⁷ 4s²
Electrons per shell: 2, 8, 15, 2 — that's 2 in the outermost shell.
About Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. Like nickel, cobalt in the Earth's crust is found only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.
- Discovered by Georg Brandt
- Appearance: hard lustrous gray metal
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.