Oxygen vs Astatine
| Property | O Oxygen | At Astatine |
|---|---|---|
| Atomic number | 8 | 85 |
| Symbol | O | At |
| Name | Oxygen | Astatine |
| Category | nonmetal | halogen |
| Standard Atomic Weight | 15.9994 u | 210 u |
| Period | 2 | 6 |
| Group | 16 | 17 |
| Block | p | p |
| Phase at STP | gas | solid |
| Electron configuration | [He]2s22p4 | [Xe]6s24f145d106p5 |
| Oxidation states | [-2, -1, 0, 1, 2] | [-1, 1, 3, 5, 7] |
| Electronegativity (Pauling) | 3.44 | 2.2 |
| Electron affinity | 1.4611 eV | 2.391 eV |
| Density | 1.429 kg/m³ | 7000 kg/m³ |
| Melting point | -218.79 °C | 301.85 °C |
| Boiling point | -182.95 °C | -273.15 °C |
| Discovery year | 1771 | 1940 |