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Question
State three reasons why you think air is a mixture and water is a compound.
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Solution
Air is a mixture because:
- It contains two or more pure substances.
- It can be separated into simpler substances by physical processes.
- Its composition is not fixed.
Water is a compound because:
- Water cannot be separated into its constituents i.e., hydrogen and oxygen by physical methods.
- Properties of water are entirely different from those of its constituents.
- The composition of water is fixed.
- Its constituents are present in fixed proportion by mass. Water has a definite formula (H2O).
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