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प्रश्न
Two drops of dilute sulphuric acid were added to 1 g of copper sulphate powder and then small amount of hot water was added to dissolve it (step I). On cooling, beautiful blue coloured crystals got separated (step II). Step I and Step II are:
विकल्प
physical and chemical changes respectively.
chemical and physical changes respectively.
both physical changes.
both chemicals change.
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उत्तर
both physical changes.
Explanation:
Dissolution of copper sulphate powder in water in presence of sulphuric acid is a physical change. On cooling this hot solution, the crystals of copper sulphate are separated. This is also a physical change.
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