Distillation of Water

Purifying water by distillation

• If something is dissolved in water then it can be extracted by evaporating it and then condensing the vapour, leaving the solute behind.
• Distillation is required if the water is mixed with another liquid.
• Distillation involves separating liquids according to their boiling points.
• If you heat a mixture of liquids to the boiling point of one of the liquids, you know the liquid coming off at that temperature is the one whose boiling point it is.
• Eg: If you mix ethanol and and water and heat it to 78°C, then the vapour coming off must contain alcohol, as 78°C is the boiling point of ethanol.

Simple distillation-2 liquids, different b.p.

Fractionating column - More than 2 liquids