Explanation:
It is known that common salt is NaCl and it is ionic in nature. As all ionic substances are able to dissolve in water because like dissolves like.
Hence, salt will easily dissolve in water.
On the other hand, sand is insoluble in water. Therefore, when sand is added to water then it will not dissolve in water.
Thus, we can conclude that when water is added to a sand-salt mixture then sane being insoluble will not dissolve and it will settle at the bottom after some time. Whereas salt being able to dissolve in water will readily dissolve.
