Francium
Alkali metal| Atomic number | 87 |
|---|---|
| Category | Alkali metal |
| Atomic mass | 223 |
| Electron configuration | [Rn]7s¹ |
| Oxidation states | +1 |
| Electronegativity | 0.7 |
| Melting point | 27 °C |
| Boiling point | 677 °C |
| Density | 1.87 g/cm³ |
| Crystal structure | Body-centred cubic |
| Group | 1 |
| Period | 7 |
| Block | s |
| Discovered | 1,939 |
| Crustal abundance | 0 ppm |