process of fractional distillation

• where is fractional distillation carried out?

  in a fractionating column
• where is it hottest in a fractionating column?

  the bottom of the column
• what happens in the fractionating column?

  crude oil is heated + vapourised
• what happens to the vapours of hydrocarbons with high boiling points?

  they condense at the bottom of the column
• what happens to the vapours of hydrocarbons with lower boiling points?

  they rise up the column and condense at the top