| (b) Crude oil |
| 4.7 know that crude oil is a mixture of hydrocarbons |
| 4.8 describe how the industrial process of fractional distillation separates crude oil into fractions |
| 4.9 know the names and uses of the main fractions obtained from crude oil: refinery gases, gasoline, kerosene, diesel, fuel oil and bitumen |
| 4.10 know the trend in colour, boiling point and viscosity of the main fractions |
| 4.11 know that a fuel is a substance that, when burned, releases heat energy |
| 4.12 know the possible products of complete and incomplete combustion of hydrocarbons with oxygen in the air |
| 4.13 understand why carbon monoxide is poisonous, in terms of its effect on the capacity of blood to transport oxygen references to haemoglobin are not required |
| 4.14 know that, in car engines, the temperature reached is high enough to allow nitrogen and oxygen from air to react, forming oxides of nitrogen |
| 4.15 explain how the combustion of some impurities in hydrocarbon fuels results in the formation of sulfur dioxide |
| 4.16 understand how sulfur dioxide and oxides of nitrogen oxides contribute to acid rain |
| 4.17 describe how long-chain alkanes are converted to alkenes and shorter-chain alkanes by catalytic cracking (using silica or alumina as the catalyst and a temperature in the range of 600–700oC) |
| 4.18 explain why cracking is necessary, in terms of the balance between supply and demand for different fractions |
