Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
As fuels
19 practice questions
Practice questions
1–10 of 19
Question 1
1 mark · Easy
Answer and see the solution →State the name of the process used to separate crude oil into fractions based on their different boiling points.
Question 2
3 marks · Easy
Answer and see the solution →Methane is a hydrocarbon fuel. Answer the following questions about its combustion.
(a)[1 mark]Write a word equation for the complete combustion of methane.
(b)[1 mark]Give the names of the two products formed in this reaction.
(c)[1 mark]Explain why methane releases energy when it burns completely in air.
Question 3
2 marks · Easy
Answer and see the solution →Incomplete combustion of hydrocarbons can take place when there is insufficient oxygen available. Explain, using your knowledge of combustion, why incomplete combustion of hydrocarbons does not produce as much energy as complete combustion.
Question 4
3 marks · Easy
Answer and see the solution →The table below shows approximate boiling points for some fractions separated from crude oil using fractional distillation. Complete the table by filling in the missing fraction names.
Fraction Approximate Boiling Point (C) Refinery gases <40 ___ 40–180 Kerosene 180–260 ___ >350 Question 5
1 mark · Easy
Answer and see the solution →State one product, other than carbon dioxide, formed during the incomplete combustion of a hydrocarbon fuel.
Question 6
3 marks · Easy
Answer and see the solution →The diagram shows a simplified fractional distillation column for crude oil. The temperature at three different positions is marked.
Fractionating column (simplified, labelled) The temperature at the bottom is 370 C, in the middle is 220 C, and at the top is 40 C.
(a)[1 mark]State what happens to the hydrocarbons as their vapours rise up the column.
(b)[1 mark]Name the fraction collected at the top of the column.
(c)[1 mark]Explain why some hydrocarbons are collected at the bottom instead of higher up.
Question 7
2 marks · Easy
Answer and see the solution →Crude oil is separated in a fractionating column. A crude oil sample produces 100 kg of gasoline, 60 kg of kerosene, and 30 kg of diesel oil after fractional distillation. The total mass of these fractions is collected.
Calculate the percentage by mass of the gasoline fraction in the sample. Give your answer to 1 decimal place.
Question 8
2 marks · Easy
Answer and see the solution →A hydrocarbon burns in exactly 20 g of oxygen during complete combustion. Calculate the mass of carbon dioxide produced if all the oxygen is converted into carbon dioxide. (Assume all atoms from oxygen go into making carbon dioxide; ignore water formation for this calculation. Relative atomic masses: C = 12, O = 16)
Question 9
2 marks · Normal
Answer and see the solution →State the name of the process used to separate crude oil into useful fractions and give one reason why crude oil must be separated in this way.
Question 10
4 marks · Normal
Answer and see the solution →This question is about combustion of hydrocarbons.
(a)[1 mark]Write the word equation for the complete combustion of propane.
(b)[1 mark]State the two main products formed during complete combustion of a hydrocarbon.
(c)[2 marks]Explain, using your knowledge of incomplete combustion, why burning a hydrocarbon in a limited supply of air may produce a dangerous gas.