Nitrogen vs Oxygen
Together they are 99% of every breath — yet one is lazy at making bonds and the other is greedy for them.
Side by side
| Property | Nitrogen | Oxygen |
|---|---|---|
| Symbol | N | O |
| Atomic number (Z) | 7 | 8 |
| Atomic mass | 14.007 u | 15.999 u |
| Category | Nonmetal | Nonmetal |
| Group | 15 | 16 |
| Period | 2 | 2 |
| Phase at room temp | gas | gas |
| Electron configuration | [He] 2s^2 2p^3 | [He] 2s^2 2p^4 |
| Valence electrons | 5 | 6 |
| Atomic radius | 56 pm | 48 pm |
| Electronegativity | 3.04 | 3.44 |
| First ionisation energy | 1402 kJ/mol | 1314 kJ/mol |
The verdicts
- Bigger atom: Nitrogen — the lower an element sits in its group, the more shells it wears.
- Greedy electron-taker: Oxygen — higher electronegativity means it pulls shared electrons harder.
- Heavier: Oxygen — compare the atomic masses in the table above.
Want the visual version with bars for radius, electronegativity and ionisation energy? Open the interactive compare tool with this pair already loaded.