37 Rb
Alkali metal
Rubidium
Used in atomic clocks.
Properties of Rubidium
- Atomic number (Z)
- 37
- Symbol
- Rb
- Atomic mass
- 85.468 g/mol
- Category
- Alkali metal
- Group
- 1
- Period
- 5
- Electron configuration
- [Kr] 5s¹
- Electronegativity (Pauling)
- 0.82
- Atomic radius
- 265 pm
- First ionization energy
- 403 kJ/mol
- Melting point
- 312.46 K (39.3 °C)
- Boiling point
- 961 K (687.9 °C)
- Density
- 1.532 g/cm³
- Phase at 25 °C
- Solid
- Discovered
- Discovered in 1861