Hydrogen vs Oxygen
| Property | H Hydrogen | O Oxygen |
|---|---|---|
| Atomic number | 1 | 8 |
| Symbol | H | O |
| Name | Hydrogen | Oxygen |
| Category | nonmetal | nonmetal |
| Standard Atomic Weight | 1.007975 u | 15.9994 u |
| Period | 1 | 2 |
| Group | 1 | 16 |
| Block | s | p |
| Phase at STP | gas | gas |
| Electron configuration | 1s1 | [He]2s22p4 |
| Oxidation states | [-1, 1] | [-2, -1, 0, 1, 2] |
| Electronegativity (Pauling) | 2.2 | 3.44 |
| Electron affinity | 0.75419 eV | 1.4611 eV |
| Density | 0.08988 kg/m³ | 1.429 kg/m³ |
| Melting point | -259.34 °C | -218.79 °C |
| Boiling point | -252.87 °C | -182.95 °C |
| Discovery year | 1766 | 1771 |