27 - Cobalt transition metal
Discovered by Georg Brandt in 1735
- Atomic Radius (Å)
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.
Shell | Electrons | Orbitals |
---|---|---|
1 | 2 | 2 in 1s |
2 | 8 | 2 in 2s + 6 in 2p |
3 | 15 | 2 in 3s + 6 in 3p + 7 in 3d |
4 | 2 | 2 in 4s |
58.93 u
Atomic Mass
1.7 Å
Atomic Radius
3200 K
Boiling Point
1.26 Å
Covalent Radius
8.9 g/cm³
Density
63.9
Electron Affinity
1.88
Electronegativity
7.88 eV
First Ionization Energy
1768.15 K
Melting Point
4
Number of Shells
27
Atomic Number
2, 8, 15, 2
Electron Shell Occupations