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Is Matter Around Us Pure? — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceIs Matter Around Us Pure?3 Marks
Question
Is air a mixture or a compound? Give three reasons for your answer.
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Answer

Air is a mixture because:
  1. Air can be separated into its constituents like oxygen, nitrogen, etc. by physical process of fractional distillation.
  2. Air shows the properties of all the gases present in it.
  3. Liquid air does not have a fixed boiling point.

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