The main constituent of natural gas is methane= CH4
Describe petroleum as…
- A mixture of hydrocarbons … and its separation into useful fractions by fractional distillation
- different hydrocarbons have different carbon chain lengths, with longer chain carbon chains having higher boiling points
- their different boiling points means petroleum can be separated by fractional distillation:
○ a large fraction column with petroleum is heated
○ different hydrocarbons boil and rise up as gases, which can then be collected separately
Describe the properties of molecules within a fraction
- ● Some properties of hydrocarbons depend on the size of their molecules. These properties influence their use as fuels.
- ● The shorter the molecules, the lower the temperature at which that fraction evaporates or condenses – and the lower its boiling point.
- ● Shorter the molecules, the less viscous it is. (more runny)
Name the uses of the fractions as:
- ● Refinery gas for bottled gas for heating and cooking
- ● Gasoline fraction for fuel (petrol) in cars
- ● Naphtha fraction for making chemicals
- ● Kerosene/paraffin fraction for jet fuel
- ● Diesel oil/gas oil for fuel in diesel engines
- ● Fuel oil fraction for fuel for ships and home heating systems
- ● Lubricating fraction for lubricants, waxes and polishes
- ● Bitumen for making roads