Question
Write down the composition of three main gases present in air by volume.
✓
Answer
| Composition of air by volume | |
| Nitrogen | 78% |
| Oxygen | 21% |
| Carbon dioxide | 0.03-0.04% |
| Inert gases | 0.9% |
| Water vapours | Variable |
| Bust particles | Variable |
| Other impurities | Variable |
| Gases | Percentage | Figure |
| Nitrogen | 78% |  |
| Oxygen | 21% | |
| Carbon dioxide | 0.03-0.04% | |
| Inert gases | 0.9% | |
| Water vapours | Variable | |
| Bust particles | Variable | |
| Other impurities | Variable |
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