Francium (Fr)
Francium (Fr) is element 87, an alkali metal. Atomic mass 223, configuration [Rn] 7s¹. Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 87 |
|---|---|
| Symbol | Fr |
| Standard atomic weight | 223 |
| Category | Alkali Metal |
| Group | 1 |
| Period | 7 |
| State at room temperature | Liquid (predicted) |
| Electron configuration | [Rn] 7s¹ |
| Valence electrons | 1 |
| Common oxidation states | +1 |
| Common ions | No common ions |
| Electronegativity (Pauling) | 0.7 |
| First ionization energy | 380 kJ/mol |
| Electron affinity | 44.38 kJ/mol |
| Melting point | ~27°C |
| Boiling point | ~650°C |
Common uses
- Research only (due to extreme scarcity and radioactivity)
Where it matters
- Fundamental Physics (Parity violation studies)
Hazards
- Highly radioactive
History
| Discovered | 1939 |
|---|---|
| Discovered by | Marguerite Perey |
| Name | From France |