Question

Which of the following mixture cannot be separated by using water as the solvent ?
(a) copper sulphate and sand
(b) sand and potash alum
(c) sand and sulphur
(d) sugar and sand

Answer 1

(A) copper sulphate and sand
After adding water leave the solution for some time . The sand particles settle down ( sedimentation) and pour the rest of the solution in another container ( decantation) . Smaller sand particles can be separated by filtration. You can separate the copper sulphate by crystallisation.