27 · Co
Cobalt
Established as a metal by Brandt in 1735.
Identity
- Atomic number
- 27
- Symbol
- Co
- Canonical name
- Cobalt
- Category
- transition metal
- Group
- 9
- Period
- 4
- Block
- d
Properties
These quantities come from the Periodic Table JSON compilation. They have not yet been checked, one by one, against CIAAW atomic weights or NIST measurements. A value marked estimated is not a measurement.
- Atomic mass
- 58.933194 u
- Electron configuration
- [Ar] 3d7 4s2
- Electrons per shell
- 2, 8, 15, 2
- Standard state
- solid
- Density
- 8.9 g/cm³
- Melting point
- 1,768 K
- Boiling point
- 3,200 K
- Electronegativity
- 1.88 Pauling
- First ionization energy
- 760.4 kJ/mol
- Electron affinity
- 63.898 kJ/mol
Notable isotopes
This summary is not an inventory of every isotope.
- Co-59 · 100 % · stable
History
A metal distinct from bismuth
Discovery · confirmed · 1735
Brandt shows that the blue of smalt comes from a metal, cobalt, and not from bismuth.
Etymology
- Theme
- mythology
- Language
- allemand
- Root
- Kobold
- Meaning
- kobold, a mine spirit
Scientists
Places and institutions
- Stockholm — historical setting : Sweden — present country : Sweden
See also
Sources
- IUPAC, Periodic Table of the Elements
- Bowserinator, Periodic Table JSON. Compilation secondaire d’où viennent les grandeurs physiques importées (masse, densité, températures, énergies). Elles ne sont pas revérifiées une à une auprès du NIST ou de la CIAAW.
- John Emsley, Nature’s Building Blocks: An A–Z Guide to the Elements