Question

How will you prepare crystals of alum? Explain.

Answer 1

Prepare a supersaturated solution of alum in a china dish by dissolving the powdered alum in water. Add the alum to the water and dissolve it until it reaches its saturation point. Heat the solution. After some time, the water starts to evaporate. Heat the solution until the entire water in the solution gets evaporated. Switch off the flame and observe. The residue of crystalline substance can be seen. Allow the dish to cool to recover the crystals of alum.