Electrolysis — Paper 1 · IGCSE Chemistry (9-1) 0971

9 What is observed at each electrode when molten lead(II) bromide is electrolysed using platinum electrodes? negative electrode positive electrode A bubbles of a colourless gas bubbles of a brown gas B bubbles of a colourless gas bubbles of a colourless gas C shiny grey liquid bubbles of a brown gas D shiny grey liquid bubbles of a colourless gas

1 marks

Answer: C

This question in 0971/11 May/June 2018

10 Four substances are electrolysed using inert electrodes. Which row describes the electrode products? substance anode product cathode product A concentrated aqueous sodium chloride hydrogen chlorine B concentrated hydrochloric acid chlorine oxygen C dilute sulfuric acid oxygen hydrogen D molten lead bromide lead bromine

1 marks

Answer: C

This question in 0971/11 May/June 2019

10 The apparatus used for electrolysis is shown. power supply electrodes electrolyte Which statement is correct? A Copper forms at the anode in some electrolysis reactions. B Hydrogen forms at the cathode in some electrolysis reactions. C Oxygen forms at the cathode in some electrolysis reactions. D The negative electrode is called the anode.

1 marks

Answer: B

This question in 0971/12 Oct/Nov 2019

9 Which products are formed when dilute sulfuric acid undergoes electrolysis? at the anode at the cathode A oxygen hydrogen B hydrogen oxygen C sulfur dioxide hydrogen D oxygen sulfur dioxide

1 marks

Answer: A

This question in 0971/11 May/June 2020

9 Dilute sulfuric acid is electrolysed using carbon electrodes. Which row shows the products formed at each electrode? anode cathode A hydrogen oxygen B hydrogen sulfur C oxygen hydrogen D oxygen sulfur

1 marks

Answer: C

This question in 0971/12 May/June 2020

13 Universal indicator solution is added to a neutral solution of concentrated aqueous sodium chloride. The solution, which contains H+ (hydrogen), Na+ (sodium), Cl – (chloride) and OH– (hydroxide) ions, is electrolysed. The product at the cathode is hydrogen gas and the product at the anode is chlorine gas. What happens to the colour of the indicator in the solution during electrolysis? A The colour changes from blue to green. B The colour changes from blue to red. C The colour changes from green to blue. D The colour changes from green to red.

1 marks

Answer: C

This question in 0971/12 Oct/Nov 2020

10 In separate experiments, electricity was passed through concentrated aqueous sodium chloride and molten lead(II) bromide. What would happen in both experiments? A A halogen would be formed at the anode. B A metal would be formed at the cathode. C Hydrogen would be formed at the anode. D Hydrogen would be formed at the cathode.

1 marks

Answer: A

This question in 0971/11 May/June 2021

10 Iron can be electroplated with zinc to make it resistant to corrosion. Which row about electroplating iron with zinc is correct? positive electrode negative electrode electrolyte (anode) (cathode) A iron zinc iron nitrate B iron zinc zinc nitrate C zinc iron iron nitrate D zinc iron zinc nitrate

1 marks

Answer: D

This question in 0971/12 Oct/Nov 2021

26 Which row describes the method of extraction of aluminium and iron from their ores? aluminium iron A electrolysis electrolysis B electrolysis reduction with carbon C reduction with carbon electrolysis D reduction with carbon reduction with carbon

1 marks

Answer: B

This question in 0971/12 Oct/Nov 2021

10 The diagram shows the electrolysis of concentrated hydrochloric acid and concentrated aqueous sodium chloride using carbon electrodes. + – + – electrode 1 electrode 2 electrode 3 electrode 4 concentrated concentrated aqueous hydrochloric acid sodium chloride At which electrodes is hydrogen produced? A electrode 1 only B electrodes 1 and 3 C electrode 2 only D electrodes 2 and 4

1 marks

Answer: D

This question in 0971/11 May/June 2022

10 The diagram shows the electrolysis of concentrated hydrochloric acid and concentrated aqueous sodium chloride using carbon electrodes. + – + – electrode 1 electrode 2 electrode 3 electrode 4 concentrated concentrated aqueous hydrochloric acid sodium chloride At which electrodes is hydrogen produced? A electrode 1 only B electrodes 1 and 3 C electrode 2 only D electrodes 2 and 4

1 marks

Answer: D

This question in 0971/12 May/June 2022

10 The electrolysis of concentrated aqueous sodium chloride and molten sodium chloride is shown. + – electrode 1 + – + – electrode 2 concentrated aqueous molten sodium chloride sodium chloride What are the products at electrodes 1 and 2? electrode 1 electrode 2 A chlorine chlorine B hydrogen chlorine C hydrogen sodium D sodium sodium

1 marks

Answer: B

This question in 0971/12 Oct/Nov 2022

9 Concentrated aqueous sodium chloride is electrolysed using inert electrodes. Gases X and Y are produced at the electrodes shown. X Y concentrated aqueous sodium chloride – + – + What are X and Y? X Y A chlorine hydrogen B hydrogen chlorine C hydrogen oxygen D oxygen hydrogen

1 marks

Answer: B

This question in 0971/11 May/June 2023

9 Dilute sulfuric acid is electrolysed using inert electrodes. The apparatus is set up as shown. dilute sulfuric acid graphite graphite cathode anode – + 30 cm3 of a gas is collected at the cathode. A different gas is collected at the anode. Which row is correct? volume of gas gas at gas at collected at anode cathode anode / cm3 A hydrogen oxygen 15 B hydrogen oxygen 30 C oxygen hydrogen 15 D oxygen hydrogen 30

1 marks

Answer: A

This question in 0971/12 May/June 2023

11 Which statement about electrolysis is correct? A Bromine and hydrogen are formed during the electrolysis of molten lead(II) bromide. B Metals are formed at the positive electrode. C Molten covalent compounds are broken down by electricity. D Platinum is used as an inert electrode.

1 marks

Answer: D

This question in 0971/12 Oct/Nov 2023

10 Dilute sulfuric acid and lead(II) bromide are electrolysed separately. Which statements are correct? 1 Colourless gases are produced when dilute sulfuric acid is electrolysed. 2 Lead(II) bromide can be electrolysed when molten. 3 Lead is formed at the positive electrode when lead(II) bromide is electrolysed. 4 Sulfate ions are produced at the negative electrode when dilute sulfuric acid is electrolysed. A 1 and 2 B 1 and 3 C 2 and 3 D 3 and 4

1 marks

Answer: A

This question in 0971/11 May/June 2024

13 In an experiment, a molten compound is broken down using electricity. Which row identifies the negative electrode and the general name for the molten compound being broken down? general name for negative the molten electrode compound A anode electrolysis B anode electrolyte C cathode electrolyte D cathode electrolysis

1 marks

Answer: C

This question in 0971/12 May/June 2024

11 Three substances are listed. 1 solid copper 2 aqueous sodium bromide 3 solid lead(II) bromide Which substances conduct electricity? A 1, 2 and 3 B 1 and 2 only C 1 and 3 only D 2 and 3 only

1 marks

Answer: B

This question in 0971/12 Oct/Nov 2024

13 Molten sodium sulfide, Na2S, is electrolysed using inert electrodes. Which row identifies the product at each electrode? cathode anode A sodium sulfur B sulfur sodium C hydrogen sulfur D sodium hydrogen

1 marks

Answer: A

This question in 0971/12 Oct/Nov 2024

11 Concentrated aqueous sodium chloride is electrolysed using inert electrodes. What is the main product formed at the positive electrode (anode)? A chlorine B hydrogen C oxygen D sodium

1 marks

Answer: A

This question in 0971/11 May/June 2025

12 The diagram shows a simple electrolytic cell for an electrolysis experiment. X + – Y Z Three parts of the electrolytic cell are labelled X, Y and Z. Which row shows the correct labels to replace X, Y and Z in the diagram? X Y Z A anode cathode aqueous salt B anode cathode solid salt C cathode anode aqueous salt D cathode anode solid salt

1 marks

Answer: A

This question in 0971/12 May/June 2025

12 What is the product at each electrode when molten silver iodide is electrolysed using inert electrodes? cathode anode A hydrogen iodine B iodine silver C silver iodine D silver oxygen

1 marks

Answer: C

This question in 0971/12 Oct/Nov 2025

13 Which row describes a product at each electrode when dilute sulfuric acid is electrolysed using inert electrodes? product at anode product at cathode A 10 cm3 of a colourless gas 10 cm3 of a brown gas B 10 cm3 of a colourless gas 20 cm3 of a colourless gas C 20 cm3 of a colourless gas 10 cm3 of a colourless gas D 20 cm3 of a brown gas 10 cm3 of a colourless gas

1 marks

Answer: B

This question in 0971/12 Oct/Nov 2025