Fractional Distillation

1. Crude Oil is heated strongly to evaporate it

2. Hot vapours are led into the bottom of the fractionating column. The hottest at the bottom and becomes cooler towards the top.

3. The vapours cool down as they rise though it.

4. When the vapour reaches a part of the column that is cool enough they condense.

5. The liquid falls into a tray and is piped out

Long Chain Alkanes → Bottom of column, High Boiling point, High Viscosity, Low Volatility point, Low flammability.

Short Chain Alkanes → Top of Column, Low boiling point, Low Viscosity, High Volatility, High Flamability.

Distillation - Boiling Points

Viscosity - How runny it is.

Volatility - How esaily it evaporates.

Flammability - How easy it is to ignite.

Long Chain Alkanes make poor fuels.

- They are solid at room temperature, not very         

flammable and are difficult to ignite.

Short Chain Alkanes are good fuels.

- Gases at room temperature, ignite easily

- Bulky to store, stored under pressure as

liquids