Two hydrocarbons, J and K, are present in vapours entering a fractionating column below the middle outlet.
The middle and upper outlets collect liquids that condense in the section immediately below each outlet.
| Hydrocarbon | Boiling point in ∘C^\circ\text{C}∘C |
|---|---|
| J | 185 |
| K | 100 |
A cooling fault changes the temperatures at the outlets.
| Outlet | Temperature during normal operation in ∘C^\circ\text{C}∘C | Temperature during the cooling fault in ∘C^\circ\text{C}∘C |
|---|---|---|
| Middle | 170 | 200 |
| Upper | 80 | 110 |
Explain how the outlet at which each hydrocarbon is collected changes during the cooling fault.
91 exam-style questions on AQA GCSE Chemistry 7.1 Carbon compounds as fuels and feedstock, covering 7.1.1 Crude oil, hydrocarbons and alkanes, 7.1.2 Fractional distillation and petrochemicals, 7.1.3 Properties of hydrocarbons, and 7.1.4 Cracking and alkenes. Each one has a worked solution and a mark scheme showing where the marks go.