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प्रश्न
Describe a method to separate a mixture of common salt and sand.
उत्तर
Separation of common salt and sand from a mixture involves the processes of filtration, followed by evaporation.
Sand can be separated from a mixture of sand and salt solution (salt dissolved in water) by filtration. After filtration, sand remains on the filter paper as a residue. Common salt can now be obtained from the filtrate by boiling it. Boiling causes all the water to evaporate and salt is left behind. This process is called evaporation.
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