Atomic number 37
Rubidium
Alkali metal
Quick facts
- Atomic mass
- 85.468
- Group
- 1
- Period
- 5
- State (STP)
- solid
- Electronegativity
- 0.82
- Common ox. states
- +1
Properties
Electron configuration
[Kr] 5s¹
- Ionization energy
- 403.0 kJ/mol
- Electron affinity
- 46.9 kJ/mol
- Melting point
- 312.45 K (39.3 °C)
- Boiling point
- 961.00 K (687.9 °C)
How it bonds
Rubidium follows the alkali-metal script: lose one electron, become Rb⁺. Even more reactive than potassium. Catches fire in air, explodes in water.