Potassium vs Roentgenium
| Property | K Potassium | Rg Roentgenium |
|---|---|---|
| Atomic number | 19 | 111 |
| Symbol | K | Rg |
| Name | Potassium | Roentgenium |
| Category | alkali-metal | transition-metal |
| Standard Atomic Weight | 39.0983 u | 281 u |
| Period | 4 | 7 |
| Group | 1 | 11 |
| Block | s | s |
| Phase at STP | solid | N/A |
| Electron configuration | [Ar]4s1 | [Rn] 7s2 5f14 6d9(predicted) |
| Oxidation states | [-1, 1] | [-1, 1, 3, 5] |
| Electronegativity (Pauling) | 0.82 | N/A |
| Electron affinity | 0.5014 eV | 1.6 eV |
| Density | 890 kg/m³ | 2.870000e+4 kg/m³ |
| Melting point | 63.38 °C | -273.15 °C |
| Boiling point | 758.85 °C | -273.15 °C |
| Discovery year | 1807 | 1994 |