Physical and chemical changes — Paper 1 · IGCSE Science - Combined 0653

23 Which of the reactions shown is a thermal decomposition? A calcium carbonate → calcium oxide + carbon dioxide B methane + air → carbon dioxide + water C sodium carbonate + hydrochloric acid → sodium chloride + water + carbon dioxide D sodium hydroxide + hydrochloric acid → sodium chloride + water

1 marks

Answer: A

This question in 0653/11 Oct/Nov 2005

23 When glucose, C6H12O6, is heated in a test-tube, it can form carbon and water. This change is an example of A combustion. B decomposition. C distillation. D evaporation.

1 marks

Answer: B

This question in 0653/11 May/June 2006

22 Which equation shows the thermal decomposition of a compound? A CaCO3 → CaO + CO2 B 2H2 + O2 → 2H2O C NaOH + HNO3 → NaNO3 + 2H2O D 3H2 + N2 → 2NH3

1 marks

Answer: A

This question in 0653/11 May/June 2007

23 Which word equation shows a thermal decomposition? A ammonia + nitric acid → ammonium nitrate B hydrogen + oxygen → water C magnesium carbonate → magnesium oxide + carbon dioxide D potassium chloride + silver nitrate → potassium nitrate + silver chloride

1 marks

Answer: C

This question in 0653/11 Oct/Nov 2007

17 What does a word equation show? the changes that the speed of occur in a reaction a reaction A v v B v x Cc x v D x x

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2008

25 What happens to a piece of magnesium when it burns in air? A oxidation and combustion B oxidation and thermal decomposition C reduction and combustion D reduction and thermal decomposition

1 marks

Answer: A

This question in 0653/12 May/June 2010

24 The equations for two reactions are shown. X PbCO3 → PbO + CO2 Y CH4 + 2O2 → CO2 + 2H2O Which types of reaction are X and Y? X Y A combustion neutralisation B combustion thermal decomposition C thermal decomposition combustion D thermal decomposition neutralisation

1 marks

Answer: C

This question in 0653/11 Oct/Nov 2010

26 The equations for two reactions are shown. X PbCO3 → PbO + CO2 Y CH4 + 2O2 → CO2 + 2H2O Which types of reaction are X and Y? X Y A combustion neutralisation B combustion thermal decomposition C thermal decomposition combustion D thermal decomposition neutralisation

1 marks

Answer: C

This question in 0653/12 Oct/Nov 2010

24 The equations for two reactions are shown. X PbCO3 → PbO + CO2 Y CH4 + 2O2 → CO2 + 2H2O Which types of reaction are X and Y? X Y A combustion neutralisation B combustion thermal decomposition C thermal decomposition combustion D thermal decomposition neutralisation

1 marks

Answer: C

This question in 0653/13 Oct/Nov 2010

23 Which chemical equation represents a thermal decomposition reaction? A CH4 + 2O2 → CO2 + 2H2O B HCl + NaOH → NaCl + H2O C H2 + Cl 2 → 2HCl D MgCO3 → MgO + CO2

1 marks

Answer: D

This question in 0653/11 May/June 2011

24 Which chemical equation represents a thermal decomposition reaction? A CH4 + 2O2 → CO2 + 2H2O B HCl + NaOH → NaCl + H2O C H2 + Cl 2 → 2HCl D MgCO3 → MgO + CO2

1 marks

Answer: D

This question in 0653/12 May/June 2011

15 Which reaction involves combustion? A calcium carbonate → calcium oxide + carbon dioxide B methane + oxygen → carbon dioxide + water C sodium carbonate + hydrochloric acid → sodium chloride + water + carbon dioxide D sodium hydroxide + hydrochloric acid → sodium chloride + water

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2013

15 Which reaction involves combustion? A calcium carbonate → calcium oxide + carbon dioxide B methane + oxygen → carbon dioxide + water C sodium carbonate + hydrochloric acid → sodium chloride + water + carbon dioxide D sodium hydroxide + hydrochloric acid → sodium chloride + water

1 marks

Answer: B

This question in 0653/12 Oct/Nov 2013

16 Which word equation shows a thermal decomposition? A ammonia + nitric acid → ammonium nitrate B hydrogen + oxygen → water C magnesium carbonate → magnesium oxide + carbon dioxide D potassium chloride + silver nitrate → potassium nitrate + silver chloride

1 marks

Answer: C

This question in 0653/13 Oct/Nov 2014

17 The diagram shows the apparatus used for the electrolysis of lead(II) bromide using inert electrodes X and Y. Lead is formed at electrode Y. lamp electrode X electrode Y lead Which statement about the electrolysis is correct? A A green gas is given off at electrode X. B Electrode Y is the anode. C Only a physical change takes place when a current is passed. D The electrolyte is in the molten state.

1 marks

Answer: D

This question in 0653/12 May/June 2016

26 Which reaction involves combustion? A calcium carbonate → calcium oxide + carbon dioxide B methane + oxygen → carbon dioxide + water C sodium carbonate + hydrochloric acid → sodium chloride + water + carbon dioxide D sodium hydroxide + hydrochloric acid → sodium chloride + water

1 marks

Answer: B

This question in 0653/12 May/June 2016

26 Which reaction involves combustion? A calcium carbonate → calcium oxide + carbon dioxide B methane + oxygen → carbon dioxide + water C sodium carbonate + hydrochloric acid → sodium chloride + water + carbon dioxide D sodium hydroxide + hydrochloric acid → sodium chloride + water

1 marks

Answer: B

This question in 0653/13 May/June 2016

16 Which process is a physical change? A the combustion of methane B the electrolysis of aqueous copper chloride C the melting of ice D the reaction of sodium with water

1 marks

Answer: C

This question in 0653/12 Oct/Nov 2016

18 What does a word equation show? the changes that the speed of occur in a reaction a reaction A Jv Jv B Jv x Cc x v D x x

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2016

20 Solid ammonium nitrate is soluble in water. When a large quantity of ammonium nitrate is added to water, the water freezes. Which statement describes this change? A an endothermic chemical change B an endothermic physical change C an exothermic chemical change D an exothermic physical change

1 marks

Answer: B

This question in 0653/12 Feb/March 2017

15 Which process produces a chemical change? A adding ethanol to water B adding sodium to water C boiling water D melting ice

1 marks

Answer: B

This question in 0653/11 May/June 2017

15 Which process is a physical change? A adding zinc to dilute sulfuric acid B bubbling carbon dioxide through limewater C electrolysing molten lead bromide D separating petroleum by fractional distillation

1 marks

Answer: D

This question in 0653/12 May/June 2017

15 Which process is a physical change? A adding zinc to dilute sulfuric acid B bubbling carbon dioxide through limewater C electrolysing molten lead bromide D separating petroleum by fractional distillation

1 marks

Answer: D

This question in 0653/13 May/June 2017

16 Which row describes chemical changes and physical changes? chemical changes physical changes A the mass of the products is always new substances are made the same as the mass of the reactants B the mass of the products is always there is no mass change the same as the mass of the reactants C the mass of the products is sometimes new substances are made more or less than the mass of the reactants D the mass of the products is sometimes there is no mass change more or less than the mass of the reactants

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2017

16 What is a physical change? A carbon dioxide turning limewater milky B the crystallisation of copper sulfate from solution C the electrolysis of molten lead(II) bromide D the thermal decomposition of calcium carbonate

1 marks

Answer: B

This question in 0653/12 Oct/Nov 2017

16 Which row describes the type of change for each process? sodium reacting melting ice with water A chemical physical B chemical chemical C physical physical D physical chemical

1 marks

Answer: D

This question in 0653/13 Oct/Nov 2017

16 Some changes are listed. 1 boiling 2 decomposing 3 evaporating 4 oxidising Which changes are physical changes? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

1 marks

Answer: B

This question in 0653/11 May/June 2018

26 Which chemical reactions produce carbon dioxide? hydrochloric hydrochloric acid acid complete + + combustion | respiration calcium sodium of methane carbonate hydroxide A Jv x Jv WA B Jv x Jv x Cc Jv x x Jv D x Jv Jv WA

1 marks

Answer: A

This question in 0653/11 May/June 2018

16 Which process involves a physical change? A adding magnesium to nitric acid B burning methane C evaporating petroleum D rusting iron

1 marks

Answer: C

This question in 0653/12 May/June 2018

16 Which process involves a physical change? A adding magnesium to nitric acid B burning methane C evaporating petroleum D rusting iron

1 marks

Answer: C

This question in 0653/13 May/June 2018

18 The temperature of aqueous copper sulfate is measured. After three minutes, magnesium is stirred into the solution. The temperature of the mixture is recorded every minute. The results are shown. 60 50 40 temperature / °C 30 20 10 0 0 3 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 time / minutes Which description of the chemical reaction is correct? A endothermic then exothermic B endothermic only C exothermic then endothermic D exothermic only

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2018

14 Four processes are listed. 1 melting of ice 2 electrolysis of molten lead(II) bromide 3 combustion of carbon 4 rusting of iron Which processes are chemical changes? A 1 and 3 only B 1, 2 and 3 C 2 and 4 only D 2, 3 and 4

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2019

14 Four changes are listed. 1 solid carbon dioxide → carbon dioxide gas 2 the rusting of iron 3 the electrolysis of molten sodium chloride 4 the fractional distillation of crude oil Which row identifies the chemical changes and physical changes? chemical change physical change A 1 and 2 3 and 4 B 1 and 4 2 and 3 C 2 and 3 1 and 4 D 3 and 4 1 and 2

1 marks

Answer: C

This question in 0653/12 Oct/Nov 2019

14 Four changes are listed. 1 solid carbon dioxide → carbon dioxide gas 2 the rusting of iron 3 the electrolysis of molten sodium chloride 4 the fractional distillation of crude oil Which row identifies the chemical changes and physical changes? chemical change physical change A 1 and 2 3 and 4 B 1 and 4 2 and 3 C 2 and 3 1 and 4 D 3 and 4 1 and 2

1 marks

Answer: C

This question in 0653/13 Oct/Nov 2019

16 Which processes are physical changes? 1 burning methane gas 2 dissolving sugar in water 3 evaporating ethanol 4 melting an ice cube 5 rusting of iron A 1, 3 and 4 B 1, 4 and 5 C 2, 3 and 4 D 2, 3 and 5

1 marks

Answer: C

This question in 0653/12 Oct/Nov 2020

15 What is an example of a physical change? A carbon dioxide turning limewater milky B the crystallisation of copper(II) sulfate from solution C the electrolysis of molten lead(II) bromide D the thermal decomposition of calcium carbonate

1 marks

Answer: B

This question in 0653/11 May/June 2021

14 What is an example of a physical change? A carbon dioxide turning limewater milky B the crystallisation of copper(II) sulfate from solution C the electrolysis of molten lead(II) bromide D the thermal decomposition of calcium carbonate

1 marks

Answer: B

This question in 0653/12 May/June 2021

15 What is an example of a physical change? A carbon dioxide turning limewater milky B the crystallisation of copper(II) sulfate from solution C the electrolysis of molten lead(II) bromide D the thermal decomposition of calcium carbonate

1 marks

Answer: B

This question in 0653/13 May/June 2021

16 Which process is not a chemical change? A electrolysis of molten lead bromide B fractional distillation of petroleum C oxidation of copper D rusting of iron

1 marks

Answer: B

This question in 0653/11 Oct/Nov 2021

17 Potassium reacts with water in an exothermic reaction. potassium + water  … X … + … Y … What are substances X and Y? X Y A potassium oxide hydrogen B potassium hydroxide hydrogen C potassium oxide oxygen D potassium hydroxide oxygen

1 marks

Answer: B

This question in 0653/12 Feb/March 2022

15 Which row describes a chemical change? test result A one end of a piece of aluminium is heated the other end gets hot B calcium carbonate is heated carbon dioxide is made C a piece of iron is heated it becomes more malleable D a beaker of water is heated steam is made

1 marks

Answer: B

This question in 0653/11 May/June 2022

15 Three changes are listed. 1 Dilute hydrochloric acid is reacted with aqueous sodium hydroxide. 2 The mixture formed is then heated until all of the water is evaporated. 3 The solid that is formed is then heated until it melts. Which row describes changes 1, 2 and 3? 1 2 3 A chemical chemical physical B chemical physical physical C physical physical chemical D physical chemical chemical

1 marks

Answer: B

This question in 0653/12 May/June 2022

15 When solid sodium carbonate is added to dilute hydrochloric acid, it dissolves and carbon dioxide is given off. Which statement is correct? A This is a chemical change because sodium carbonate dissolves. B This is a chemical change because the acid reacts with sodium carbonate. C This is a physical change because sodium carbonate dissolves. D This is a physical change because the acid reacts with sodium carbonate.

1 marks

Answer: B

This question in 0653/13 May/June 2022

17 When solid sodium carbonate and dilute hydrochloric acid are mixed, a reaction occurs. During this reaction, carbon dioxide is released and the temperature of the mixture increases. Which chemical terms describe this reaction? 1 exothermic 2 neutralisation 3 thermal decomposition 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 0653/12 Oct/Nov 2023

15 Which processes are physical changes? 1 burning methane gas 2 dissolving sugar in water 3 evaporating ethanol 4 melting an ice cube 5 rusting of iron A 1, 3 and 4 B 1, 4 and 5 C 2, 3 and 4 D 2, 3 and 5

1 marks

Answer: C

This question in 0653/11 May/June 2024

14 Four processes are listed. 1 melting of ice 2 electrolysis of molten lead(II) bromide 3 combustion of carbon 4 rusting of iron Which processes are chemical changes? A 1, 2 and 3 B 1 and 3 only C 2, 3 and 4 D 2 and 4 only

1 marks

Answer: C

This question in 0653/11 Oct/Nov 2024

15 Some changes are listed. 1 boiling 2 decomposing 3 evaporating 4 oxidising Which changes are physical changes? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

1 marks

Answer: B

This question in 0653/12 Oct/Nov 2024

15 Some changes are listed. 1 boiling 2 decomposing 3 evaporating 4 oxidising Which changes are physical changes? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

1 marks

Answer: B

This question in 0653/13 Oct/Nov 2024

17 Which process is a physical change? A electrolysis B melting C oxidation D polymerisation

1 marks

Answer: B

This question in 0653/12 Feb/March 2025

19 The evaporation of ethanol is an example of a … 1 … change because … 2 … . Which words complete gaps 1 and 2? 1 2 A chemical a gas is produced B chemical no new compound is formed C physical a gas is produced D physical no new compound is formed

1 marks

Answer: D

This question in 0653/11 May/June 2025

20 Which statement indicates that a chemical change occurs? A Energy is absorbed. B There is a change in colour. C There is a change of state. D There is no change in mass.

1 marks

Answer: B

This question in 0653/12 May/June 2025

19 Which process results in a chemical change? A Heat liquid water to form steam. B Mix powdered carbon and iron filings. C Melt iron filings. D Heat sulfur in air to make sulfur dioxide.

1 marks

Answer: D

This question in 0653/13 May/June 2025

16 Which process involves a chemical change? A condensation B evaporation C melting D oxidation

1 marks

Answer: D

This question in 0653/11 Oct/Nov 2025