Krypton vs Astatine
| Property | Kr Krypton | At Astatine |
|---|---|---|
| Atomic number | 36 | 85 |
| Symbol | Kr | At |
| Name | Krypton | Astatine |
| Category | noble-gas | halogen |
| Standard Atomic Weight | 83.798 u | 210 u |
| Period | 4 | 6 |
| Group | 18 | 17 |
| Block | p | p |
| Phase at STP | gas | solid |
| Electron configuration | [Ar]4s23d104p6 | [Xe]6s24f145d106p5 |
| Oxidation states | [0, 1, 2] | [-1, 1, 3, 5, 7] |
| Electronegativity (Pauling) | 3 | 2.2 |
| Electron affinity | -1 eV | 2.391 eV |
| Density | 3.733 kg/m³ | 7000 kg/m³ |
| Melting point | -157.36 °C | 301.85 °C |
| Boiling point | -153.42 °C | -273.15 °C |
| Discovery year | 1898 | 1940 |