Potassium |
| Symbol | K |
|---|---|
| Latin name | Kalium |
| Atomic number | 19 |
| Period | 4 |
| Element category | Alkali metals |
| Relative atomic mass | 39.0983 |
| Group | I.A |
| Electronegativity | 0.9 |
| Oxidation numbers | 1 |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 4s1 |
| Density [g/cm3] | 0.862 |
| State | Solid |
| Melting point [°C] | 93.65 |
| Boiling point [°C] | 760 |
| Critical point [°C] | 1950 |
| Critical pressure [MPa] | 16 |
| Atomic radius [pm] | 243 |
| Covalent radius [pm] | 196 |
| Thermal conductivity [W m-1K-1] | 102.5 |
| Heat capacity [J K-1g-1] | 0.757 |
| Discovery | 1807 |
| Hardness [Mohs scale] | 0.5 |
| Brinell hardness [MPa] | 0.363 |
| Electrical conductivity [S m-1] | 1.64 · 107 |
| 1.st ionization energy [eV] | 4.3407 |
| 2.nd ionization energy [eV] | 31.625 |
| 3.rd ionization energy [eV] | 45.72 |
| Stable isotopes | 3 |
| Unstable isotopes | 8 |