Redox — Paper 1 · IGCSE Sciences - Co-ordinated (9-1) 0973

19 Which reaction involves both oxidation and reduction? A calcium carbonate → calcium oxide + carbon dioxide B copper oxide + carbon → copper + carbon dioxide C silver nitrate + potassium chloride → silver chloride + potassium nitrate D sulfuric acid + sodium hydroxide → sodium sulfate + water

1 marks

Answer: B

This question in 0973/11 May/June 2020

19 Which reaction involves both oxidation and reduction? A calcium carbonate → calcium oxide + carbon dioxide B copper oxide + carbon → copper + carbon dioxide C silver nitrate + potassium chloride → silver chloride + potassium nitrate D sulfuric acid + sodium hydroxide → sodium sulfate + water

1 marks

Answer: B

This question in 0973/12 May/June 2020

19 Which word equation represents a redox reaction? A carbon + copper oxide  copper + carbon dioxide B hydrochloric acid + potassium hydroxide  potassium chloride + water C magnesium carbonate  magnesium oxide + carbon dioxide D sodium sulfate + barium nitrate  barium sulfate + sodium nitrate

1 marks

Answer: A

This question in 0973/11 Oct/Nov 2020

18 The catalytic converter in the exhaust of a car brings about the reaction shown. 2NO + 2CO + 2CO, + No Which row about this reaction is correct? 0 0O WwW D> oxidation ~ « reduction «x \ x key J/ = occurs X = does not occur

1 marks

Answer: A

This question in 0973/11 May/June 2021

18 The catalytic converter in the exhaust of a car brings about the reaction shown. 2NO + 2CO + 2CO, + No Which row about this reaction is correct? 0 0O WwW > oxidation ~ «4 reduction <x \ x key J/ = occurs X = does not occur

1 marks

Answer: A

This question in 0973/12 May/June 2021

24 The diagram shows a metal being extracted from its powdered ore using carbon. a mixture of carbon and powdered ore What happens to the ore in this reaction? A It burns. B It decomposes. C It is oxidised. D It is reduced.

1 marks

Answer: D

This question in 0973/11 May/June 2022

24 The diagram shows a metal being extracted from its powdered ore using carbon. a mixture of carbon and powdered ore What happens to the ore in this reaction? A It burns. B It decomposes. C It is oxidised. D It is reduced.

1 marks

Answer: D

This question in 0973/12 May/June 2022

20 Which statement shows that methane, CH4, is oxidised when it burns? A The products of the reaction are gaseous. B The products of the reaction are water and carbon dioxide. C The reaction is exothermic. D The total number of oxygen atoms has increased during the reaction.

1 marks

Answer: B

This question in 0973/11 May/June 2023

20 Iron is extracted from its ore in the blast furnace. One of the reactions involved is shown. Fe2O3 + 3CO → 2Fe + 3CO2 Which statement is correct? A Iron(III) oxide and carbon monoxide are both oxidised. B Iron(III) oxide and carbon monoxide are both reduced. C Iron(III) oxide is oxidised and carbon monoxide is reduced. D Iron(III) oxide is reduced and carbon monoxide is oxidised.

1 marks

Answer: D

This question in 0973/12 May/June 2023

19 When petrol burns in a car engine, carbon monoxide, CO, and nitrogen monoxide, NO, are produced. These gases pass through a catalytic converter where carbon monoxide reacts with nitrogen monoxide. The equation for the reaction is shown. carbon monoxide + nitrogen monoxide → nitrogen + carbon dioxide Which statement is not correct? A Carbon monoxide is oxidised in the catalytic converter. B Carbon monoxide is produced by the complete combustion of petrol. C Nitrogen from the air is oxidised in the car engine. D Nitrogen monoxide is reduced in the catalytic converter.

1 marks

Answer: B

This question in 0973/11 Oct/Nov 2023

21 Which reactions involve oxidation? 1 C + O2  CO2 2 2NaOH + H2SO4  Na2SO4 + 2H2O 3 2Mg + O2  2MgO 4 CaCO3  CaO + CO2 A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

1 marks

Answer: A

This question in 0973/11 May/June 2024

19 The equation for the reaction between iron(III) oxide, Fe2O3, and carbon is shown. 2Fe2O3 + 3C  4Fe + 3CO2 Which statement about this reaction is correct? A C is oxidised. B CO2 is reduced. C Fe is oxidised. D Fe2O3 is oxidised.

1 marks

Answer: A

This question in 0973/12 May/June 2024

21 Which statement about oxidation is correct? A It occurs when an element or compound chemically combines with oxygen. B It occurs when an element or compound forms a mixture with oxygen. C It occurs when an element or compound is separated from a mixture with oxygen. D It occurs when a compound loses oxygen.

1 marks

Answer: A

This question in 0973/11 Oct/Nov 2024

22 Which equation shows the oxidation of a metal? A CuO + H2  Cu + H2O B CuO + Zn  Cu + ZnO C Fe2O3 + 3CO  2Fe + 3CO2 D 2ZnO + C  2Zn + CO2

1 marks

Answer: B

This question in 0973/11 May/June 2025