Helium vs Lead
| Property | He Helium | Pb Lead |
|---|---|---|
| Atomic number | 2 | 82 |
| Symbol | He | Pb |
| Name | Helium | Lead |
| Category | noble-gas | post-transition-metal |
| Standard Atomic Weight | 4.002602 u | 207.2 u |
| Period | 1 | 6 |
| Group | 18 | 14 |
| Block | s | p |
| Phase at STP | gas | solid |
| Electron configuration | 1s2 | [Xe]6s24f145d106p2 |
| Oxidation states | [0] | [-4, -2, -1, 0, 1, 2, 3, 4] |
| Electronegativity (Pauling) | N/A | 2.33 |
| Electron affinity | -0.5 eV | 0.364 eV |
| Density | 0.1785 kg/m³ | 1.134200e+4 kg/m³ |
| Melting point | -272.2 °C | 327.46 °C |
| Boiling point | -268.93 °C | 1748.85 °C |
| Discovery year | 1868 | 2021 |