Central heating boilers can also burn kerosene.
Kerosene is produced from crude oil in a fractionating column using fractional distillation.
In the first step, crude oil is heated and hydrocarbon vapours are formed.
Explain how kerosene is produced from these hydrocarbon vapours.

Fractional distillation is a process used to separate crude oil, which is a complex mixture of hydrocarbons, into simpler, more useful mixtures called fractions. 1. **Heating:** The crude oil is heated to a high temperature (around 350°C), causing most of the hydrocarbons to evaporate and turn into a gas (vapour). 2. **Fractionating Column:** This mixture of vapours is pumped into the bottom of a tall fractionating column. The column has a temperature gradient – it is very hot at the bottom and gradually gets cooler towards the top. 3. **Separation:** The hot vapours rise up the column. As they rise, they cool down. Hydrocarbons have different chain lengths and therefore different boiling points. - Hydrocarbons with long chains have high boiling points. They condense back into a liquid at lower levels in the column where it is still hot. - Hydrocarbons with short chains have low boiling points. They continue to rise further up the column to where it is cooler before they condense. 4. **Collection:** Kerosene consists of hydrocarbons with medium chain lengths and medium boiling points. Therefore, the kerosene vapours will rise part-way up the column and condense into liquid on trays in the middle section, where the temperature matches their boiling point range. They are then piped off.