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Question
A mixture has a variable composition. Give three other reasons why air is considered a mixture and not a compound.
Solution
Air is a mixture because :
- Air has no formula, a mixture has no formula whereas the compound has a formula.
- No energy changes are involved to form air from various gases.
- When air is formed out of its constituents no change in mass nor change in volume takes place.
- Properties of air vary from place to place and from time to time. i.e. there is more CO2 in towns as compared to villages where more oxygen prevales as compared to towns.
- Components of air can be separated by simple physical methods.
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