8. The best way to obtain pure, solid household salt from a solid mixture of household salt and sand is to:
A: add water, stir and leave the solution to completely evaporate
B: filter, add water, stir and then evaporate the filtrate
C: add water, stir, filter and evaporate the filtrate
D: heat the mixture, add water, stir and leave the solution to form crystals

The best way to obtain pure, solid household salt from a solid mixture of household salt and sand is to "add water, stir, filter and evaporate the filtrate".

Option: C

Explanation:

The salt and sand can be separated on the basis of solubility, as we know the salt is chemically known as sodium chloride, which have good solubility in water. The most general method is the mixture is taken into a flask or beaker and water is added with stirring, where salt get dissolved and sand remain as it is, because NaCl is capable enough to form hydrogen bonding with water, while sand have absence of such property. Then this solution containing insoluble sand is filtered by using filter paper. The sand is received in filter paper while filtrate in beaker is evaporated by boiling it in order to receive salt as residue.