The least soluble component will crystallize out first, leaving the other components in solution. By controlling the temperature, it is sometimes possible to remove each component in turn. Fractional Distillation Fractional distillation is similar to distillation, but uses an additional piece of apparatus called a fractionating column. A fractionating column contains glass rings or balls which provide a large surface area for condensation and re-evaporation. The vapour of the liquid with the lowest boiling point reaches the top of the column first.
Fractional distillation is used to separate liquids with close boiling points.
Fractionating Column A fractionating column is added before the condenser in fractional distillation and contains glass rings or balls which provide a large surface area for condensation and re-evaporation. The Frasch Process is a method of obtaining sulphur from underground deposits using a tube consisting of three concentric pipes. Superheated steam is passed down the outer pipe to melt the sulphur, which is then forced up through the intermediate pipe by compressed air from the inner tube. The steam in the outer casing keeps the sulphur molten in the pipe. Free Radical A Free radical is an atom, or group of atoms, which normally exist only in combination with other atoms, but which may exist independently for short periods during the course of a chemical reaction or for longer periods under special conditions.