Separation techniques Chemistry 
Separation by difference in particle size:
Sieving:
- Is a way pf separating mixtures of solids, or solids and liquids with different sized particles
- The mixture is poured through a sieve and the particles smaller than the sieve pass through while the larger particles are trapped by the sieve
- The are commonly used for cooking
- E.g. a mixture of rice and water is poured through a sieve to capture rice and remove the water
Filtration
- Is a technique commonly used for mixtures of solids and liquid, particularly when solids particles are quite small and again depending on the size of the particle.
- The liquid or solution is poured into filter paper and the liquid passes through the filter and the solid or residue is trapped by the filter paper
- The liquid or solution that passes through is called the filtrate
Separation by difference in boiling point
Vaporisation
- Is most commonly used to to retrieve a solid that has being dissolved in a liquid
- For example where the is a solution
- The liquid component of the solution the solvent is converted to vapour by either boiling the solution or allowing it to evaporate leaving behind the dissolved solid the solute
- Boiling is a much quicker process than evaporation and therefore is more commonly used
- The technique is based on the large differences in boiling points of the solute and solvent
- THIS TECHNIQUE DOES NOT RECOVER THE LIQUID
Distillation or simple distillation
- This is a technique of separating two or more liquids or separating the liquid from the solids in a solution but also retrieving the liquid component
- This technique relies on a difference of at least 50ºC in boiling point between components to obtain an effective separation
- The mixture to be separated is placed in a round bottom flask and heated to boiling
- The vapour rises up the neck of the flask and then flows into the water cooler condenser
- The vapour that condensers back to a liquid is called a distillate
- If the boiling points are
Sieving:
- Is a way pf separating mixtures of solids, or solids and liquids with different sized particles
- The mixture is poured through a sieve and the particles smaller than the sieve pass through while the larger particles are trapped by the sieve
- The are commonly used for cooking
- E.g. a mixture of rice and water is poured through a sieve to capture rice and remove the water
Filtration
- Is a technique commonly used for mixtures of solids and liquid, particularly when solids particles are quite small and again depending on the size of the particle.
- The liquid or solution is poured into filter paper and the liquid passes through the filter and the solid or residue is trapped by the filter paper
- The liquid or solution that passes through is called the filtrate
Separation by difference in boiling point
Vaporisation
- Is most commonly used to to retrieve a solid that has being dissolved in a liquid
- For example where the is a solution
- The liquid component of the solution the solvent is converted to vapour by either boiling the solution or allowing it to evaporate leaving behind the dissolved solid the solute
- Boiling is a much quicker process than evaporation and therefore is more commonly used
- The technique is based on the large differences in boiling points of the solute and solvent
- THIS TECHNIQUE DOES NOT RECOVER THE LIQUID
Distillation or simple distillation
- This is a technique of separating two or more liquids or separating the liquid from the solids in a solution but also retrieving the liquid component
- This technique relies on a difference of at least 50ºC in boiling point between components to obtain an effective separation
- The mixture to be separated is placed in a round bottom flask and heated to boiling
- The vapour rises up the neck of the flask and then flows into the water cooler condenser
- The vapour that condensers back to a liquid is called a distillate
- If the boiling points are