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प्रश्न
Differentiate between:
pure and impure substances
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उत्तर
Pure substances —
- Pure substances have definite composition and definite physical and chemical properties.
- They are all homogeneous i.e. their composition is uniform throughout the bulk.
- Examples: Elements and compounds.
Impure substances —
- Impure substances are made up of two or more pure substances mixed together in any proportion.
- They may be homogeneous or hetergeneous i.e. their composition is not uniform throughout the bulk.
- They are all mixtures.
Examples: air, sea water, petroleum, a solution of sugar in water are all impure substances.
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