| Attribute | Value |
|---|---|
| Symbol | Rb |
| Standard state | Solid |
| Atomic mass | 85.468 u |
| Electron configuration | [Kr]5s¹ |
| Oxidation states |
|
| Electronegativity (pauling scale) | 0.82 |
| Atomic radius (van der waals) | 303 pm |
| Ionization energy | 4.177 eV |
| Electron affinity | 0.468 eV |
| Melting point | 312.46 K |
| Boiling point | 961 K |
| Density | 1.53 g/cm³ |
| Atomic number | 37 |
| Group name | Alkali metal |
| Discovered | 1861 year |