Francium vs Dubnium
| Property | Fr Francium | Db Dubnium |
|---|---|---|
| Atomic number | 87 | 105 |
| Symbol | Fr | Db |
| Name | Francium | Dubnium |
| Category | alkali-metal | transition-metal |
| Standard Atomic Weight | 223 u | 268 u |
| Period | 7 | 7 |
| Group | 1 | 5 |
| Block | s | s |
| Phase at STP | solid | N/A |
| Electron configuration | [Rn]7s1 | [Rn]7s25f146d3 |
| Oxidation states | [1] | [3, 4, 5] |
| Electronegativity (Pauling) | 0.7 | N/A |
| Electron affinity | 0.491 eV | 0.56 eV |
| Density | 1870 kg/m³ | 2.930000e+4 kg/m³ |
| Melting point | 26.85 °C | -273.15 °C |
| Boiling point | -273.15 °C | -273.15 °C |
| Discovery year | 1939 | 1967 |