Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
The Halogens
86 practice questions
Topics covered
Practice questions
11–15 of 15 · Hard
Question 11
5 marks · Hard
Answer and see the solution →This question is about explaining halogen reactivity in terms of electronic configuration.
(a)[1 mark]State, in terms of electron shells, the difference in the position of the outer electrons of a chlorine atom and a bromine atom.
(b)[2 marks]Explain, in terms of electronic configuration, why a chlorine atom is more reactive than a bromine atom.
(c)[1 mark]A chlorine atom reacts to form a chloride ion. Write the electron configuration for the chloride ion.
(d)[1 mark]Using your answers and knowledge of shells, describe what happens, in terms of electrons, when bromine forms a bromide ion.
Question 12
2 marks · Hard
Answer and see the solution →Astatine is the element below iodine in Group 7 of the Periodic Table.
Predict the colour and state of astatine at room temperature. Justify your predictions using group trends.
Question 13
7 marks · Hard
Answer and see the solution →This question is about the properties and reactions of halogens.
(a)[2 marks]State the physical state and colour of bromine and iodine at room temperature (20 °C).
(b)Aqueous chlorine is added to a solution containing potassium iodide. The solution changes colour.
(i)[2 marks]Write the ionic equation, including state symbols, for the reaction that takes place.
(ii)[2 marks]Explain why chlorine can displace iodine from potassium iodide solution but not the other way around.
(iii)[1 mark]Identify the oxidising agent and the substance that is reduced in this reaction.
Question 14
7 marks · Hard
Answer and see the solution →This question is about halogens and redox processes in their reactions.
(a)[2 marks]Describe the appearance and physical state of chlorine and iodine at room temperature.
(b)Bromine water is added to a solution of potassium iodide. The following reaction occurs:
(i)[2 marks]In terms of oxidation and reduction, explain which species is reduced and which is oxidised in the reaction.
(ii)[3 marks]State the colour change that is observed during this reaction. Explain the reason for this change.
Question 15
8 marks · Hard
Answer and see the solution →This question is about the reactions between halogens and halide ions.
(a)[2 marks]Chlorine water is added to a solution of sodium bromide.
Write the ionic equation for the reaction that takes place.
(b)[2 marks]Explain why chlorine is able to displace bromine from sodium bromide solution but not the other way around.
(c)The reaction between chlorine and sodium bromide is a redox reaction.
For this reaction:
(i)[2 marks]Identify which species is oxidised and which is reduced.
(ii)[2 marks]Use your knowledge of electron transfer to explain your answer to part (c)(i).