Crystallisation and Evaporation


Crystallisation is a separation technique used to separate a solvent from a solution, producing solid crystals. When the solution is heated, some of the solvent evaporates, which leaves behind a more concentrated solution

First. it is important to understand what solvent, solute and a solution are.

  • Solute – The solid which will be dissolved
  • Solvent – The liquid that the solid will be dissolved into
  • Solution – The mixture that is formed

In crystallisation, the solvent is evaporated, leaving the solute behind.

Evaporation is used to separate soluble solids from a solution

  1. A mixture is placed in the evaporating basin
  2. A Bunsen burner is used to heat the mixture in the basin
  3. The liquid begins to evaporate, reducing its amount and the solid begins to be visible around the basin
  4. Stop the heat before all the solid has evaporated
  5. When the remaining solution has cooled, pour away or filter the excess liquid
  6. After all the water has evaporated, solid crystals will be left behind
  7. Dry the crystals in air or a warm oven