Filtration and crystallisation

• What techniques can separate solids from liquids?

  Filtration, evaporation, and crystallization
• What is a mixture of a liquid and an insoluble solid called?

  A mixture
• What do we call a liquid with a soluble solid dissolved in it?

  A solution
• In a solution, what is sodium chloride referred to as?

  Solute
• What is the role of water in a solution of sodium chloride?

  Solvent
• How does filtration work in separating solids from liquids?

  It uses filter paper to trap solids
• What is the purpose of filter paper in filtration?

  To allow liquids to pass through
• What happens when a soluble solid is dissolved in a liquid?

  It forms a solution
• What are the two options for separating a soluble solid from a liquid?

  Evaporation or crystallization
• What equipment is used for evaporation in separating solids?

  Evaporating dish or crucible
• What is the effect of heating a solution in evaporation?

  It causes the solvent to evaporate
• What is a potential issue with evaporation for some solids?

  They may undergo thermal decomposition
• What is the first step in crystallization?

  Place the solution in an evaporation dish
• How should the solution be heated during crystallization?

  Gently, possibly using a water bath
• What happens as the solution cools during crystallization?

  More crystals start to form
• What is the final step after filtering crystals from the solution?

  Dry the crystals
• What can be done to dry the crystals after filtering?

  Leave them somewhere warm or use an oven
• What are the steps involved in the process of crystallization?

  1. Place solution in an evaporation dish
  2. Heat gently (use water bath)
  3. Stop heating when crystals form
  4. Filter out crystals from solution
  5. Dry the crystals