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37
Rb
85.468
Rubidium
Alkali metals · Group 1 · Period 5
Atomic properties
| Atomic number | 37 |
|---|---|
| Symbol | Rb |
| Standard atomic weight | 85.468 |
| Classification | Alkali metals |
| Group | 1 |
| Period | 5 |
| Block | s-block |
| Electron configuration | [Kr] 5s1 |
| Electronegativity (Pauling) | 0.82 |
| Common oxidation states | +1 |
Physical properties
| Phase at 20 °C | Solid |
|---|---|
| Density | 1.532 g/cm³ |
| Melting point | 39.30 °C |
| Boiling point | 688 °C |
| Discovered | 1861 |
| CAS number | — |