Francium vs Radium
| Property | Fr Francium | Ra Radium |
|---|---|---|
| Atomic number | 87 | 88 |
| Symbol | Fr | Ra |
| Name | Francium | Radium |
| Category | alkali-metal | alkaline-earth-metal |
| Standard Atomic Weight | 223 u | 226 u |
| Period | 7 | 7 |
| Group | 1 | 2 |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Rn]7s1 | [Rn]7s2 |
| Oxidation states | [1] | [2] |
| Electronegativity (Pauling) | 0.7 | 0.9 |
| Electron affinity | 0.491 eV | 0.096 eV |
| Density | 1870 kg/m³ | 5000 kg/m³ |
| Melting point | 26.85 °C | 699.85 °C |
| Boiling point | -273.15 °C | 1139.85 °C |
| Discovery year | 1939 | 1898 |