Fractional Distillation: Fractional Distillation is used to separate two liquids based on their boiling points.
An example would be separating ethanol from water. Ethanol has a lower boiling water than water (at about 780C), therefore, the heating is monitored (using the thermometer) to ensure that the temperature does not reach 1000C (the boiling point of water). Anyways, the ethanol would turn into a vapour and travel out of the flask. It would then condense into its liquid form with the help of the cooling water and fall into the beaker.