Hafnium vs Astatine
| Property | Hf Hafnium | At Astatine |
|---|---|---|
| Atomic number | 72 | 85 |
| Symbol | Hf | At |
| Name | Hafnium | Astatine |
| Category | transition-metal | halogen |
| Standard Atomic Weight | 178.49 u | 210 u |
| Period | 6 | 6 |
| Group | 4 | 17 |
| Block | s | p |
| Phase at STP | solid | solid |
| Electron configuration | [Xe]6s24f145d2 | [Xe]6s24f145d106p5 |
| Oxidation states | [-2, 0, 1, 2, 3, 4] | [-1, 1, 3, 5, 7] |
| Electronegativity (Pauling) | 1.3 | 2.2 |
| Electron affinity | 0.178 eV | 2.391 eV |
| Density | 1.330000e+4 kg/m³ | 7000 kg/m³ |
| Melting point | 2232.85 °C | 301.85 °C |
| Boiling point | 4602.85 °C | -273.15 °C |
| Discovery year | 1911 | 1940 |