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प्रश्न
What are the characteristic properties of a pure substance? Why do we need them?
उत्तर
Pure substance : Pure substances have a definite set of properties such as boiling point, melting point, density, etc. They are all homogeneous i.e., their composition is uniform throughout the bulk. Both elements and compounds are pure substances.
Pure substances are needed to :
- Manufacture medicines.
- To prepare chemicals in industry.
- For scientific purposes.
- To maintain the good health of human beings.
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