Separation Techniques

Separation Techniques

1. Immiscible = the liquids don't mix properly and one floats on top of the other = like pouring oil onto water.

2. Miscible = Mixes properly = like putting milk in a cup of tea.

3. SEPARATING FUNNEL

   • Two immiscible liquids are shaken together. when they are left to stand, the liquids separate into two layers. the denser liquid sinks to the bottom and the less dense floats to the top. the tap at the bottom of the separating funnel is opened and lets some of the bottom layer out into a beaker.

4. FRACTIONAL DISTILLATION

   • The miscible liquids must have different boiling points for this to work so they condense at different temperatures so can be collected separately.
     • Liquid air = filter the air to remove dust. Cool the air to around -200 degrees C to make it condense into a miscible mixture of liquids. during cooling, water vapour condenses and is removed. Carbon dioxide freezes and is then removed. the liquefied air then enters the fractionating column and is heated slowly. the remaining gases are separated by fractional distillation. oxygen and argon come out together so another column is needed for that.