Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
281–290 of 785
Question 281
5 marks · Easy
Answer and see the solution →Crude oil is very important in modern life. It is separated into fractions for different uses.
(a)[1 mark]State what crude oil is mainly made of.
(b)[1 mark]Crude oil is separated into fractions. Give one example of a product obtained from a fraction of crude oil and state its use.
(c)[2 marks]Describe how the viscosity and colour of hydrocarbon liquids change as the size of their molecules increases.
(d)[1 mark]Explain why larger hydrocarbon molecules have higher boiling points than smaller ones.
Question 282
5 marks · Easy
Answer and see the solution →Burning fuels from crude oil can cause air pollution and environmental problems. These fuels can be separated into different fractions with different properties and uses.
(a)[2 marks]Explain how burning fuels from crude oil can contribute to acid rain. State one pollutant involved.
(b)[1 mark]Give one way in which using fractions with larger hydrocarbon molecules can increase air pollution compared to using fractions with smaller molecules.
(c)[2 marks]State one property and one use of the gasoline fraction from crude oil.
Question 283
5 marks · Easy
Answer and see the solution →The oil in underground rocks forms over a long time and is separated into fractions by boiling.
(a)[1 mark]State how crude oil forms from ancient sea plants and animals.
(b)[1 mark]A crude oil fraction boils at 350°C. A second fraction boils at 120°C. Calculate the difference in boiling points.
(c)[2 marks]Suggest what you can conclude about the size of hydrocarbon molecules in these two fractions, based on their boiling points.
(d)[1 mark]Give one reason why smaller hydrocarbons are more useful as fuels than larger molecules.
Question 284
5 marks · Easy
Answer and see the solution →Hydrocarbons in crude oil are separated into different groups, called fractions, for different uses. These fractions have different properties.
(a)[1 mark]State what a hydrocarbon is.
(b)[1 mark]State one reason why crude oil is called a non-renewable resource.
(c)[2 marks]Describe one way the boiling point and one way the colour of a hydrocarbon fraction would change as its molecules get bigger.
(d)[1 mark]Explain why smaller hydrocarbon fractions are often used as fuels.
Question 285
6 marks · Normal
Answer and see the solution →Crude oil is separated into different fractions in an oil refinery. Some of these fractions are used as fuels in daily life.
(a)[2 marks]Describe briefly how crude oil is separated into fractions in a refinery.
(b)[2 marks]Name two main fractions obtained from fractional distillation and state one typical use for each.
(c)[1 mark]Refinery gases are an important by-product at a refinery. State one use of refinery gases.
(d)[1 mark]Give the main use of gasoline in modern society.
Question 286
6 marks · Normal
Answer and see the solution →Combustion reactions of hydrocarbons from different fractions have important uses.
(a)[1 mark]State two products formed when a hydrocarbon fuel undergoes complete combustion.
(b)[1 mark]Write a word or symbol equation for the complete combustion of methane.
(c)[2 marks]Explain why carbon monoxide is formed during incomplete combustion of hydrocarbons and why it is dangerous.
(d)[2 marks]Gasoline is commonly used as a fuel in cars. Explain why gasoline is suitable for this use.
Question 287
6 marks · Normal
Answer and see the solution →The properties and uses of fuels produced from crude oil can affect both technology and human health.
(a)[3 marks]Explain why incomplete combustion of fuels can be more harmful to health than complete combustion.
(b)[2 marks]Suggest one reason why gasoline is preferred over diesel or kerosene as a fuel for most cars.
(c)[1 mark]Apart from car fuel, state one other use of the gasoline fraction.
Question 288
6 marks · Normal
Answer and see the solution →Crude oil is separated into fractions by fractional distillation in an oil refinery. The lowest boiling point fraction is 'refinery gases', which contains a mixture of small hydrocarbons. Some of these gases are used domestically as liquefied petroleum gas (LPG).
Gasoline, another fraction, is mainly used as a fuel in cars.
(a)[2 marks]A refinery processes 50 tonnes of crude oil and produces 3 tonnes of refinery gases. Calculate the percentage by mass of refinery gases obtained from the crude oil. Give your answer to two significant figures.
(b)[4 marks]A house uses 18 kg of refinery gases (LPG) per week for heating and cooking.
Assuming the refinery gases produced in part (a) are supplied entirely for use as LPG, calculate the maximum number of houses that could be supplied for 1 year. (Take 1 year = 52 weeks).
Question 289
7 marks · Hard
Answer and see the solution →Fuels made from crude oil are widely used for transport and heating. The environmental impacts of using these fuels are an important concern.
(a)[3 marks]Explain how burning fuels obtained from crude oil can contribute to the formation of acid rain. In your answer, refer to any gases released and their effects.
(b)[2 marks]Name one use of kerosene and explain why air pollution from this use might be a concern in large cities.
(c)[2 marks]Describe one way that reducing the use of kerosene as a fuel could help the environment.
Question 290
7 marks · Hard
Answer and see the solution →Crude oil is essential to our way of life and one of its products, kerosene, is widely used.
(a)[3 marks]State what crude oil is mainly composed of, and explain what hydrocarbons are.
(b)[2 marks]Describe two properties of hydrocarbon molecules found in kerosene that make them suitable for use as fuel in jet engines.
(c)[2 marks]Give one typical use of kerosene.