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Question
Air is an important inexhaustible natural resource. It is essential for the survival of human beings, microbes, plants, and animals. The following table shows the percentage of various gases in the air.
| Contents of air | Percentage (by volume) |
| Nitrogen | 78 |
| Oxygen | 21 |
| Other (carbon dioxide, inert gases, water vapours, etc.) | 1 |
In 800 m3 of air, calculate the approximate quantities of nitrogen, oxygen, and other gases.
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Solution
Nitrogen in air = 78%, Oxygen = 21%, Others = 1%
Quantity of air = 800 m3
∴ Quantity of nitrogen in it = 800 of 78%
= `800xx78/100"m"^3`
= 624 m3
∴ Quantity of oxygen = 800 of 21%
= `800xx21/100"m"^3`
= 168 m3
∴ Quantity of other gases = 800 of 1%
= `800xx1/100"m"^3`
= 8 m3
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