Preparation of salts — Paper 2 · IGCSE Sciences - Co-ordinated (Double) 0654

20 The equation for the reaction between aqueous calcium chloride and aqueous potassium sulfate is shown. CaCl 2(aq) + K2SO4(aq) → CaSO4(s) + 2KCl (aq) Which process is not used to produce the pure salt calcium sulfate? A crystallisation of the salt from solution B filtration to collect the salt C mixing two soluble salts together D washing the salt with cold water

1 marks

Answer: A

This question in 0654/23 May/June 2017

19 Which substances react with dilute sulfuric acid to form a salt? magnesium magnesium oxide magnesium carbonate magnesium chloride

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2017

19 Which substances react with dilute sulfuric acid to form a salt? magnesium oxide magnesium carbonate magnesium chloride magnesium v v ~*~ KKK v x x v v v

1 marks

Answer: A

This question in 0654/22 Oct/Nov 2017

19 Which substances react with dilute sulfuric acid to form a salt? magnesium oxide magnesium carbonate magnesium chloride magnesium v v ~*~ KKK v x x v v v

1 marks

Answer: A

This question in 0654/23 Oct/Nov 2017

20 Hydrochloric acid and sodium hydroxide neutralise each other to form water and sodium chloride. Which method is used to make the solution crystallise? A chromatography B evaporation C filtration D fractional distillation

1 marks

Answer: B

This question in 0654/21 May/June 2019

21 Copper sulfate is made by adding an excess of copper carbonate to dilute sulfuric acid and stirring. The excess solid is removed. Most of the water is then removed. The solution is left for solid copper sulfate to form. In which order is apparatus used? A Bunsen burner, tripod and flask  filter funnel  crystallising dish B Bunsen burner, tripod and flask  crystallising dish  filter funnel C filter funnel  crystallising dish  Bunsen burner, tripod and flask D filter funnel  Bunsen burner, tripod and flask  crystallising dish

1 marks

Answer: D

This question in 0654/21 May/June 2020

20 Zinc oxide is an insoluble base. It reacts with dilute hydrochloric acid to produce zinc chloride. Zinc chloride is soluble in water. Which statement about the preparation of zinc chloride crystals is correct? A Once the reaction is complete there is no need to filter the reaction mixture. B The reaction mixture is neutral at the point that no more zinc oxide reacts. C Zinc chloride crystals are obtained by evaporation to dryness. D Zinc chloride precipitates when the solution becomes neutral.

1 marks

Answer: B

This question in 0654/22 May/June 2020

23 Which process does not produce carbon dioxide? A acid reacting with a metal B acid reacting with sodium carbonate C complete combustion of methane D respiration

1 marks

Answer: A

This question in 0654/21 Oct/Nov 2020

20 Which compound is prepared by reacting an acid with a base? A calcium oxide B copper hydroxide C hydrogen chloride D magnesium sulfate

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2020

20 Salts are made by reacting dilute hydrochloric acid with four substances. 1 magnesium 2 magnesium carbonate 3 magnesium hydroxide 4 magnesium oxide Which substances produce a gas when reacted with dilute hydrochloric acid? A 1 and 2 B 1 and 3 C 2 and 4 D 3 and 4

1 marks

Answer: A

This question in 0654/23 Oct/Nov 2020

18 Copper carbonate is insoluble in water. Which method can be used to make copper carbonate? A adding aqueous sodium carbonate to aqueous copper sulfate and filtering off the product B adding solid calcium carbonate to aqueous copper sulfate and filtering off the product C adding solid copper oxide to solid calcium carbonate and heating the mixture D heating copper metal in carbon dioxide

1 marks

Answer: A

This question in 0654/22 Feb/March 2022

14 Information about the solubility in water of some calcium compounds is listed.  Calcium hydroxide is soluble.  Calcium carbonate is insoluble.  Calcium chloride is soluble. Which method is used to prepare pure calcium chloride? A Add excess calcium hydroxide to dilute hydrochloric acid, filter, then crystallise. B Add excess calcium carbonate to dilute hydrochloric acid, filter, then crystallise. C Add excess dilute hydrochloric acid to calcium hydroxide, filter, then crystallise. D Add excess dilute hydrochloric acid to calcium carbonate, filter, then crystallise.

1 marks

Answer: B

This question in 0654/23 May/June 2022

14 A student adds excess copper oxide powder to warm dilute sulfuric acid. Aqueous copper sulfate is formed. Which method is used to remove the unreacted copper oxide? A chromatography B crystallisation C distillation D filtration

1 marks

Answer: D

This question in 0654/22 Feb/March 2023

20 Copper(II) sulfate is produced by reacting copper(II) oxide with dilute sulfuric acid. The stages in the process to produce pure dry crystals are listed. 1 Leave to crystallise in a cool place. 2 Filter the reaction mixture. 3 Press the crystals between dry filter papers. 4 Add copper(II) oxide until it is in excess. 5 Heat the filtrate to concentrate it. 6 Heat the dilute sulfuric acid. What is the correct order for these stages? A 6  4  2  5  3  1 B 6  4  1  2  5  3 C 6  4  2  5  1  3 D 4  6  2  1  5  3

1 marks

Answer: C

This question in 0654/22 May/June 2023

20 Crystals of copper(II) sulfate, a soluble salt, are made by reacting excess copper(II) oxide with dilute sulfuric acid. After filtering off the unreacted copper(II) oxide, the solution is heated until it is saturated. It is then left to cool. Which statements about this preparation are correct? 1 Excess copper(II) oxide is used in order to ensure a high yield is obtained. 2 After filtering, the solution is heated to evaporate some of the water. 3 When the saturated solution cools, crystals of copper(II) sulfate begin to appear. 4 After cooling, the water is rapidly removed by evaporation. A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

1 marks

Answer: C

This question in 0654/23 May/June 2023

21 All Group I metal compounds and all Group II metal chlorides are soluble in water. All Group II metal carbonates and barium sulfate are insoluble. Which method is used to prepare barium sulfate using barium carbonate? A direct combination of solid barium carbonate and dilute sulfuric acid B reaction of solid barium carbonate and hydrogen chloride gas, followed by reaction with dilute sulfuric acid C reaction of aqueous barium carbonate with dilute hydrochloric acid, followed by reaction with aqueous sodium sulfate D reaction of solid barium carbonate with dilute hydrochloric acid, followed by reaction with aqueous sodium sulfate

1 marks

Answer: D

This question in 0654/21 Oct/Nov 2024

20 Cobalt(II) chloride, cobalt(II) nitrate, and cobalt(II) sulfate are soluble in water. Cobalt(II) oxide and cobalt(II) carbonate are insoluble in water. Which method can be used to prepare a sample of solid cobalt(II) sulfate? A Mix aqueous sodium sulfate and aqueous cobalt(II) nitrate, then filter. B Mix excess aqueous sulfuric acid and aqueous cobalt(II) chloride, then filter and evaporate the filtrate. C Mix dilute sulfuric acid and an excess of cobalt(II) oxide, then distil. D Mix dilute sulfuric acid and an excess of cobalt(II) carbonate, then filter and evaporate the filtrate.

1 marks

Answer: D

This question in 0654/23 Oct/Nov 2024

17 Limestone contains calcium carbonate, CaCO3. It is used to neutralise nitric acid, HNO3. What is the balanced ionic equation for the reaction between calcium carbonate and nitric acid? A Ca2+ + CO3 2– + H+ + NO3 –  CaNO3 + H2O + CO2 B Ca2+ + CO3 2– + 2H+ + 2NO3 –  Ca(NO3)2 + H2O + CO2 C CO3 2– + 2H+  H2O + CO2 D CaCO3 + 2HNO3  Ca(NO3)2 + H2O + CO2

1 marks

Answer: C

This question in 0654/23 May/June 2025

20 Zinc sulfate is made by adding zinc oxide to dilute sulfuric acid. The steps used to obtain zinc sulfate crystals are listed. 1 Filter the solution to remove excess zinc oxide. 2 Warm the zinc sulfate solution. 3 Add excess zinc oxide and stir. 4 Filter and dry the crystals. What is the correct order of the steps? A 1  3  4  2 B 2  1  3  4 C 3  1  2  4 D 3  2  1  4

1 marks

Answer: C

This question in 0654/23 May/June 2025

19 Zinc sulfate is a soluble salt. Zinc sulfate is prepared by reacting zinc with dilute sulfuric acid. Which statement about this preparation is correct? A Excess dilute sulfuric acid is used and after the reaction has finished the unreacted acid is removed by evaporation. B Excess dilute sulfuric acid is used and after the reaction has finished the unreacted acid is removed by adding an aqueous base. C Excess zinc is used and after the reaction has finished the unreacted zinc is removed by filtration. D Excess zinc is used and after the reaction has finished the zinc sulfate is purified by distillation.

1 marks

Answer: C

This question in 0654/21 Oct/Nov 2025

25 The word equation shown is incomplete. acid + alkali  X + water What is X? A base B carbon dioxide C hydrogen D salt

1 marks

Answer: D

This question in 0654/22 Oct/Nov 2025