Actinium vs Curium
| Property | Ac Actinium | Cm Curium |
|---|---|---|
| Atomic number | 89 | 96 |
| Symbol | Ac | Cm |
| Name | Actinium | Curium |
| Category | actinide | actinide |
| Standard Atomic Weight | 227 u | 247 u |
| Period | 7 | 7 |
| Group | N/A | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Rn]7s26d1 | [Rn]7s25f76d1 |
| Oxidation states | [3] | [3, 4, 5, 6] |
| Electronegativity (Pauling) | 1.1 | 1.3 |
| Electron affinity | 0.35 eV | 0.277 eV |
| Density | 1.007000e+4 kg/m³ | 1.351000e+4 kg/m³ |
| Melting point | 1050.85 °C | 1344.85 °C |
| Boiling point | 3197.85 °C | 3126.85 °C |
| Discovery year | 1899 | 1944 |