Cobalt (Co)
Cobalt (Co) is element 27 of the periodic table, a transition metal in period 4 and group 9. Its standard atomic weight is 58.933194, so one mole of cobalt atoms has a mass of 58.933194 g. At room temperature it is a solid; it melts at 1494.85 °C and boils at 2926.85 °C.
| Atomic number | 27 |
|---|---|
| Symbol | Co |
| Standard atomic weight | 58.933194 |
| Molar mass | 58.933194 g/mol |
| Category | Transition metal |
| Group | 9 |
| Period | 4 |
| Block | d-block |
| Electron configuration | [Ar] 4s2 3d7 |
| Oxidation states | +3, +2 |
| Electronegativity (Pauling) | 1.88 |
| Atomic radius (van der Waals) | 192 pm |
| First ionisation energy | 7.881 eV (760.4 kJ/mol) |
| Electron affinity | 0.661 eV |
| State at room temperature | Solid |
| Melting point | 1768 K (1494.85 °C) |
| Boiling point | 3200 K (2926.85 °C) |
| Density | 8.86 g/cm³ |
| Discovered | 1735 |
Group 9
Calculate with Cobalt
Atomic weight: IUPAC CIAAW standard atomic weight. Other properties: PubChem (U.S. National Library of Medicine, public domain). Values such as melting point and radius depend on how they were measured; check a data book for precise work.