Technetium vs Actinium
| Property | Tc Technetium | Ac Actinium |
|---|---|---|
| Atomic number | 43 | 89 |
| Symbol | Tc | Ac |
| Name | Technetium | Actinium |
| Category | transition-metal | actinide |
| Standard Atomic Weight | 98 u | 227 u |
| Period | 5 | 7 |
| Group | 7 | N/A |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [Kr]5s24d5 | [Rn]7s26d1 |
| Oxidation states | [-3, -1, 1, 2, 3, 4, 5, 6, 7] | [3] |
| Electronegativity (Pauling) | 1.9 | 1.1 |
| Electron affinity | 0.55 eV | 0.35 eV |
| Density | 1.100000e+4 kg/m³ | 1.007000e+4 kg/m³ |
| Melting point | 2156.85 °C | 1050.85 °C |
| Boiling point | 4264.85 °C | 3197.85 °C |
| Discovery year | 1937 | 1899 |