Hydrogen vs Thallium
| Property | H Hydrogen | Tl Thallium |
|---|---|---|
| Atomic number | 1 | 81 |
| Symbol | H | Tl |
| Name | Hydrogen | Thallium |
| Category | nonmetal | post-transition-metal |
| Standard Atomic Weight | 1.007975 u | 204.3835 u |
| Period | 1 | 6 |
| Group | 1 | 13 |
| Block | s | p |
| Phase at STP | gas | solid |
| Electron configuration | 1s1 | [Xe]6s24f145d106p1 |
| Oxidation states | [-1, 1] | [-5, -2, -1, 1, 2, 3] |
| Electronegativity (Pauling) | 2.2 | 1.62 |
| Electron affinity | 0.75419 eV | 0.377 eV |
| Density | 0.08988 kg/m³ | 1.180000e+4 kg/m³ |
| Melting point | -259.34 °C | 303.85 °C |
| Boiling point | -252.87 °C | 1472.85 °C |
| Discovery year | 1766 | 1861 |