Barium vs Roentgenium
| Property | Ba Barium | Rg Roentgenium |
|---|---|---|
| Atomic number | 56 | 111 |
| Symbol | Ba | Rg |
| Name | Barium | Roentgenium |
| Category | alkaline-earth-metal | transition-metal |
| Standard Atomic Weight | 137.327 u | 281 u |
| Period | 6 | 7 |
| Group | 2 | 11 |
| Block | s | s |
| Phase at STP | solid | N/A |
| Electron configuration | [Xe]6s2 | [Rn] 7s2 5f14 6d9(predicted) |
| Oxidation states | [1, 2] | [-1, 1, 3, 5] |
| Electronegativity (Pauling) | 0.89 | N/A |
| Electron affinity | 0.1447 eV | 1.6 eV |
| Density | 3620 kg/m³ | 2.870000e+4 kg/m³ |
| Melting point | 726.85 °C | -273.15 °C |
| Boiling point | 1896.85 °C | -273.15 °C |
| Discovery year | 1808 | 1994 |