Why evaporation is done before crystallization?

Evaporation is performed before crystallization to concentrate the solution and remove excess solvent, which helps in the formation of pure crystals. By reducing the volume of the solution, the solute becomes supersaturated, promoting the nucleation and growth of crystals. This process also increases the efficiency of crystallization, as it allows for better control over the conditions under which crystals form. Overall, evaporation sets the stage for successful crystallization by optimizing the solute concentration.