Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Reversible Reactions and Equilibria
144 practice questions
Topics covered
- Reversibility and dynamic equilibria19 practice questions
- Reversible reactions in a sealed container18 practice questions
- The position of equilibrium20 practice questions
- Changing the pressure19 practice questions
- Changing the temperature19 practice questions
- Adding a catalyst19 practice questions
- The effect of concentration19 practice questions
Practice questions
1–10 of 144
Question 1
1 mark · Easy
Answer and see the solution →State one characteristic of a system at dynamic equilibrium.
Question 2
3 marks · Easy
Answer and see the solution →The thermal decomposition of calcium carbonate is shown below:
(a)[1 mark]Identify the symbol in the equation that shows the reaction is reversible.
(b)[1 mark]Write the name of the product formed as a gas in this reaction.
(c)[1 mark]Rewrite the equation to represent this reaction as a reversible reaction.
Question 3
2 marks · Easy
Answer and see the solution →At dynamic equilibrium in a sealed container, the rate of the forward reaction is 0.12 mol/min. Calculate the rate of the backward reaction. State your answer and give a reason.
Question 4
2 marks · Easy
Answer and see the solution →Explain why the concentration of reactants does not change once a reversible reaction has reached dynamic equilibrium in a sealed container.
Question 5
3 marks · Easy
Answer and see the solution →The table below shows the amount of solid and gas present in a sealed container at different times during a chemical reaction.
Amounts in a sealed reaction vessel over time Time (min) Solid (g) Gas (g) 0 5.0 0.0 2 4.2 0.8 4 3.9 1.1 6 3.9 1.1 (a)[1 mark]Between which times does the reaction reach equilibrium?
(b)[1 mark]Give one piece of evidence from the table for your answer to (a).
(c)[1 mark]Write a word or chemical equation for the reversible reaction that could be occurring.
Question 6
1 mark · Easy
Answer and see the solution →State the condition required for a reversible reaction to reach dynamic equilibrium.
Question 7
3 marks · Easy
Answer and see the solution →A reversible reaction between two gases in a sealed container reaches dynamic equilibrium.
(a)[1 mark]State what happens to the concentration of each gas at equilibrium.
(b)[2 marks]Explain why the concentrations behave this way at dynamic equilibrium.
Question 8
2 marks · Easy
Answer and see the solution →The dehydration of hydrated copper(II) sulfate crystals is a reversible reaction:
If 0.50 mol of is heated, how many moles of water are produced? Show your working.
Question 9
2 marks · Normal
Answer and see the solution →Hydrated cobalt(II) chloride can be heated to produce anhydrous cobalt(II) chloride and water. The process is reversible.
State the chemical equation for this reversible reaction, using the correct symbol, and explain what the symbol means.
Question 10
4 marks · Normal
Answer and see the solution →The reversible reaction between hydrogen and iodine to form hydrogen iodide can reach dynamic equilibrium in a sealed tube.
(a)[2 marks]State what is meant by dynamic equilibrium.
(b)[2 marks]Describe two conditions necessary for dynamic equilibrium to occur in this reaction.