Question

A mixture consists of sand and an aqueous salt solution. which procedure can be used to separate the sand, salt, and water from each other? (1) evaporate the water, then filter out the salt. (2) evaporate the water, then filter out the sand. (3) filter out the salt, then evaporate the water. (4) filter out the sand, then evaporate the water.

Answer 1

4. If you evaporate the water first, then the sand and salt will be nearly impossible to separate. That eliminates 1 and 2. You can't filter salt out from an aqueous solution, so that eliminates 3. 4 works because you can filter out the sand (which doesn't dissolve) then evaporate the water away from the salt.