Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Gases in the Atmosphere
86 practice questions
Topics covered
Practice questions
81–86 of 86
Question 81
7 marks · Normal
Answer and see the solution →This question is about the reactions and environmental impact of oxides and carbon dioxide.
(a)[3 marks]Describe what happens when copper(II) carbonate is heated strongly in a test tube, include the name and properties (acidic or basic) of the solid product.
(b)[1 mark]Write a balanced chemical equation for the thermal decomposition of copper(II) carbonate.
(c)[3 marks]Explain how the carbon dioxide gas formed from this reaction can contribute to global warming.
Question 82
6 marks · Normal
Answer and see the solution →This question is about the nature of oxides and the greenhouse effect.
(a)[2 marks]Magnesium and sulfur are burned separately in oxygen. State the type of oxide each element forms (acidic or basic) and explain your choice for each.
(b)Carbon dioxide is released by burning fossil fuels and contributes to the greenhouse effect.
(i)[2 marks]Describe how an increase in atmospheric carbon dioxide can affect global temperatures, according to the greenhouse effect.
(ii)[2 marks]Calculate the mass of CO₂ formed when 5.0 g of calcium carbonate are completely decomposed by heating. (Relative atomic masses: Ca = 40, C = 12, O = 16)
Question 83
6 marks · Normal
Answer and see the solution →This question is about the properties of oxides and the production of carbon dioxide from metal carbonates.
(a)[2 marks]Copper(II) carbonate is a green solid. When it is heated, a black solid and a gas are formed.
State the type of oxide produced and give one property that supports your answer.
(b)[1 mark]Write a chemical equation for the thermal decomposition of copper(II) carbonate, using symbols.
(c)[1 mark]The gas produced in this reaction is released to the atmosphere. Describe one environmental effect of increased carbon dioxide levels.
(d)[2 marks]Calcium oxide formed from heating calcium carbonate is placed in water.
What is the nature of the solution formed and how does it relate to the type of oxide?
Question 84
7 marks · Hard
Answer and see the solution →This question is about the composition of air and the environmental impact of greenhouse gases.
(a)[1 mark]State the approximate percentage by volume of oxygen in dry air.
(b)[2 marks]Explain, using your knowledge of greenhouse gases, why increasing the amount of carbon dioxide in the atmosphere matters.
(c)[2 marks]A student claims that the Earth’s atmosphere could safely be made up almost entirely of carbon dioxide, so long as there is still about 21% oxygen for breathing. Explain, using scientific reasons, whether you agree with this statement.
(d)[2 marks]State one major human activity that increases the amount of carbon dioxide in the atmosphere and explain how it contributes to environmental change.
Question 85
7 marks · Hard
Answer and see the solution →This question is about experiments to measure oxygen in air and the formation of carbon dioxide from metal carbonates.
(a)[3 marks]Describe how an experiment using wet iron filings can be used to determine the percentage of oxygen in air. Include the main steps and how the data is used.
(b)A student heats 1.50 g of copper(II) carbonate and collects 275 cm³ of gas at room temperature and pressure. (i) Name the gas collected. (ii) Write a balanced equation for the reaction. (iii) Explain why the solid left at the end of the experiment has a different colour to the original solid.
(i)[1 mark]Name the gas collected.
(ii)[1 mark]Write a balanced equation for the reaction.
(iii)[1 mark]Explain why the solid left at the end of the experiment has a different colour to the original solid.
(c)[1 mark]State and explain one precaution that should be taken when interpreting the percentage of oxygen obtained from the iron experiment.
Question 86
8 marks · Hard
Answer and see the solution →The table below shows the main gases present in dry, unpolluted air:
Approximate composition of dry air Gas Percentage by volume (%) Nitrogen 78 Oxygen 21 Argon 1 Carbon dioxide 0.04 Read the data carefully. Then refer to the information provided to answer the following questions about atmospheric composition and environmental impact.
(a)[2 marks]State the two most abundant gases in dry air and their approximate percentages by volume.
(b)[1 mark]Suggest a reason for the very low percentage of carbon dioxide, even though its environmental impact is significant.
(c)[3 marks]Describe, with reference to an experiment involving copper, how you could show that air contains about one-fifth oxygen by volume.
(d)[2 marks]Explain what is meant by the term 'greenhouse gas', and why carbon dioxide is an important greenhouse gas.