Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Acids, Bases and Salt Preparations
156 practice questions
Topics covered
- Reactions of acids18 practice questions
- Reacting acids with bases19 practice questions
- Reacting acids with carbonates19 practice questions
- Salt preparations19 practice questions
- Making soluble salts (except sodium, potassium and ammonium salts)19 practice questions
- Making sodium, potassium and ammonium salts18 practice questions
- Making insoluble salts19 practice questions
- Theories of acids and bases19 practice questions
Practice questions
11–20 of 24 · Hard
Question 11
5 marks · Hard
Answer and see the solution →You are asked to prepare a pure, dry sample of magnesium sulfate in the laboratory using insoluble magnesium carbonate and dilute sulfuric acid.
(a)[2 marks]Explain why magnesium carbonate and sulfuric acid can be used to prepare magnesium sulfate by this method.
(b)[3 marks]Describe the steps you would take to obtain a pure, dry sample of magnesium sulfate from these reactants.
Question 12
2 marks · Hard
Answer and see the solution →State the general solubility rules for carbonates and hydroxides of common metals in water.
Question 13
2 marks · Hard
Answer and see the solution →When making hydrated zinc sulfate crystals from zinc oxide and sulfuric acid, the final solution is left to cool so that crystals form. Explain, in two points, why crystallisation is used instead of evaporation to dryness to obtain hydrated salt crystals.
Question 14
5 marks · Hard
Answer and see the solution →A student prepares hydrated magnesium sulfate crystals by reacting magnesium carbonate with dilute sulfuric acid.
(a)[2 marks]Write the balanced symbol equation for the reaction between magnesium carbonate and dilute sulfuric acid.
(b)[1 mark]State the state symbols for each product.
(c)[2 marks]During the process, the solution is concentrated and then left to crystallise. Write the equation for the crystallisation step, including water of crystallisation.
Question 15
2 marks · Hard
Answer and see the solution →Describe two steps a student must carry out to obtain pure hydrated copper(II) sulfate crystals from a mixture of copper(II) oxide and dilute sulfuric acid, once the reaction has finished.
Question 16
2 marks · Hard
Answer and see the solution →Explain why methyl orange is a suitable indicator for titrations involving sodium hydroxide and hydrochloric acid. In your answer, mention what the colour change shows about the reaction mixture.
Question 17
5 marks · Hard
Answer and see the solution →A student is asked to prepare pure ammonium sulfate crystals using ammonia solution and dilute sulfuric acid in the laboratory.
(a)[2 marks]Explain why the titration method must be used instead of the excess solid method for this preparation.
(b)[2 marks]State two practical reasons why an indicator is not added to the acid and alkali mixture when making the final batch of ammonium sulfate for crystallisation.
(c)[1 mark]Describe what the student should do after mixing the correct volumes of acid and alkali, to obtain pure, dry crystals of ammonium sulfate.
Question 18
2 marks · Hard
Answer and see the solution →Give two steps the student must follow to make pure potassium chloride crystals using titration and crystallisation with potassium hydroxide and hydrochloric acid.
Question 19
2 marks · Hard
Answer and see the solution →Write the balanced ionic equation, including state symbols, for the formation of lead(II) sulfate as a precipitate from aqueous solutions.
Question 20
5 marks · Hard
Answer and see the solution →Copper(II) carbonate is an insoluble salt produced by a precipitation reaction between aqueous copper(II) sulfate and sodium carbonate.
(a)[2 marks]Write the full balanced chemical equation, including state symbols, for this reaction.
(b)[1 mark]State the formula of the spectator ions in this reaction.
(c)[2 marks]Explain why these ions are considered spectator ions.