Cobalt vs Thallium
| Property | Co Cobalt | Tl Thallium |
|---|---|---|
| Atomic number | 27 | 81 |
| Symbol | Co | Tl |
| Name | Cobalt | Thallium |
| Category | transition-metal | post-transition-metal |
| Standard Atomic Weight | 58.933194 u | 204.3835 u |
| Period | 4 | 6 |
| Group | 9 | 13 |
| Block | s | p |
| Phase at STP | solid | solid |
| Electron configuration | [Ar]4s23d7 | [Xe]6s24f145d106p1 |
| Oxidation states | [-3, -1, 0, 1, 2, 3, 4, 5] | [-5, -2, -1, 1, 2, 3] |
| Electronegativity (Pauling) | 1.88 | 1.62 |
| Electron affinity | 0.661 eV | 0.377 eV |
| Density | 8860 kg/m³ | 1.180000e+4 kg/m³ |
| Melting point | 1494.85 °C | 303.85 °C |
| Boiling point | 2926.85 °C | 1472.85 °C |
| Discovery year | 1735 | 1861 |