1. Dissolve the alum in water and after mixing separate out the sand.
2.You can separate aluminum chloride from silver through the process of sublimation (Sublimation is suitable for solid mixtures containing solid substances that can vaporize directly when heated. Examples of such substances are iodine crystals, ammonium chloride, anhydrous aluminum chloride, anhydrous iron(III) chloride and benzoic acid. The vapor is cooled away from the other component(s) and collected as solid.
3. Put naphthalene and common salt in a beaker, add water, and begin heating the water. The salt will dissolve and we can use filtration to remove the water that contains the salt.