Meitnerium vs Roentgenium
| Property | Mt Meitnerium | Rg Roentgenium |
|---|---|---|
| Atomic number | 109 | 111 |
| Symbol | Mt | Rg |
| Name | Meitnerium | Roentgenium |
| Category | transition-metal | transition-metal |
| Standard Atomic Weight | 278 u | 281 u |
| Period | 7 | 7 |
| Group | 9 | 11 |
| Block | s | s |
| Phase at STP | N/A | N/A |
| Electron configuration | [Rn]7s25f146d7(calculated) | [Rn] 7s2 5f14 6d9(predicted) |
| Oxidation states | [1, 3, 4, 6, 8, 9] | [-1, 1, 3, 5] |
| Electronegativity (Pauling) | N/A | N/A |
| Electron affinity | 1.7 eV | 1.6 eV |
| Density | 3.740000e+4 kg/m³ | 2.870000e+4 kg/m³ |
| Melting point | -273.15 °C | -273.15 °C |
| Boiling point | -273.15 °C | -273.15 °C |
| Discovery year | 1982 | 1994 |