A metal so reactive it must be kept away from air, and so essential that no cell in your body works without it.
- Atomic number
- 19
- Atomic mass
- 39.098 u
- Phase
- Solid
- Electron configuration
- [Ar] 4s¹
- Melting point
- 336.53 K · 63.4 °C
- Boiling point
- 1,032 K · 758.9 °C
- Density
- 0.89 g/cm³
- Electronegativity
- 0.82
- Period / Group
- 4 / 1
- Discovery year
- 1807