Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
The Halogens
86 practice questions
Topics covered
Practice questions
11–20 of 35 · Normal
Question 11
3 marks · Normal
Answer and see the solution →Explain why chlorine can displace bromine from potassium bromide solution, but bromine cannot displace chlorine from potassium chloride solution. In your answer, refer to the reactivity trend of halogens.
Question 12
4 marks · Normal
Answer and see the solution →The results below show the observed colour changes when halogen solutions are mixed with different potassium halide solutions.
Observed colour change when halogen solutions are added to potassium halide solutions. Added halogen solution Potassium halide solution Observation Chlorine (Cl2) Potassium bromide (KBr) orange Bromine (Br2) Potassium iodide (KI) brown Iodine (I2) Potassium chloride (KCl) no change (a)[1 mark]Which halogen is the most reactive? Give evidence from the table.
(b)[1 mark]Write a balanced chemical equation for the reaction between bromine solution and potassium iodide solution.
(c)[2 marks]Predict the result if chlorine solution is added to potassium iodide solution. Explain your answer.
Question 13
1 mark · Normal
Answer and check →Which mixture will result in a visible colour change, indicating a displacement reaction?
- A.Chlorine solution and potassium bromide solution
- B.Iodine solution and potassium chloride solution
- C.Bromine solution and potassium chloride solution
- D.Iodine solution and potassium bromide solution
Question 14
2 marks · Normal
Answer and see the solution →Write the balanced equation for the reaction between chlorine and potassium bromide. State the colour change seen during the reaction.
Question 15
4 marks · Normal
Answer and see the solution →A student investigates halogen displacement reactions.
(a)[1 mark]Describe what the student would see when bromine solution is added to potassium chloride solution.
(b)[1 mark]Explain your answer to part (a).
(c)[1 mark]Write a balanced equation for the reaction (if any) between iodine solution and potassium bromide solution.
(d)[1 mark]State the order of reactivity of chlorine, bromine and iodine.
Question 16
3 marks · Normal
Answer and see the solution →A student adds chlorine water to 40.0 cm³ of potassium iodide solution and observes the solution turns brown because iodine is produced. Assume the following equation:
The concentration of the potassium iodide solution is 0.20 mol/dm³.
(a)[1 mark]Calculate the number of moles of potassium iodide present in 40.0 cm³ of the solution. Give your answer to 2 significant figures.
(b)[1 mark]Using the equation above, calculate the maximum number of moles of iodine that can be produced from this amount of potassium iodide. Give your answer to 2 significant figures.
(c)[1 mark]State the observation you would expect if bromine water was added to potassium chloride solution instead of chlorine water to potassium iodide solution.
Question 17
2 marks · Normal
Answer and see the solution →Write the ionic equation, with state symbols, for the displacement reaction between bromine water and potassium iodide solution.
Question 18
4 marks · Normal
Answer and see the solution →Chlorine water is added to a solution of potassium bromide.
(a)[1 mark]State what you would see when chlorine water is added to potassium bromide solution.
(b)[2 marks]Explain why this reaction is an example of a redox reaction. Refer to oxidation and reduction in your answer.
(c)[1 mark]Name the oxidising agent in this reaction.
Question 19
3 marks · Normal
Answer and see the solution →Explain, in terms of electron transfer, why iodine does not displace bromine from a solution of potassium bromide. Include references to oxidation and reduction in your answer.
Question 20
4 marks · Normal
Answer and see the solution →The table shows observations from adding different halogen solutions to various potassium halide solutions:
Results of mixing halogen solutions and potassium halide solutions Halogen solution Potassium halide solution Observation Chlorine Potassium iodide Brown solution formed Bromine Potassium chloride No change Iodine Potassium bromide No change Chlorine Potassium bromide Orange solution formed (a)[1 mark]Identify which pairs in the table show a displacement reaction.
(b)[2 marks]For one of the pairs that show a displacement, write the ionic equation for the reaction.
(c)[1 mark]Explain why no change is observed in the reaction between bromine and potassium chloride.