Helium vs Chromium
| Property | He Helium | Cr Chromium |
|---|---|---|
| Atomic number | 2 | 24 |
| Symbol | He | Cr |
| Name | Helium | Chromium |
| Category | noble-gas | transition-metal |
| Standard Atomic Weight | 4.002602 u | 51.9961 u |
| Period | 1 | 4 |
| Group | 18 | 6 |
| Block | s | s |
| Phase at STP | gas | solid |
| Electron configuration | 1s2 | [Ar]3d54s1 |
| Oxidation states | [0] | [-4, -2, -1, 0, 1, 2, 3, 4, 5, 6] |
| Electronegativity (Pauling) | N/A | 1.66 |
| Electron affinity | -0.5 eV | 0.675 eV |
| Density | 0.1785 kg/m³ | 7150 kg/m³ |
| Melting point | -272.2 °C | 1906.85 °C |
| Boiling point | -268.93 °C | 2670.85 °C |
| Discovery year | 1868 | 1797 |