Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Making soluble salts (except sodium, potassium and ammonium salts)
19 practice questions
Practice questions
1–8 of 8 · Easy
Question 1
1 mark · Easy
Answer and see the solution →Write a balanced chemical equation for the reaction between magnesium and dilute sulfuric acid to form magnesium sulfate.
Question 2
3 marks · Easy
Answer and see the solution →A student is making hydrated iron(II) sulfate crystals using dilute sulfuric acid and iron(II) oxide.
(a)[1 mark]State why the student adds excess iron(II) oxide to the acid.
(b)[1 mark]Describe how the student removes the unreacted iron(II) oxide from the mixture.
(c)[1 mark]Explain what the student should do next to obtain hydrated iron(II) sulfate crystals.
Question 3
2 marks · Easy
Answer and see the solution →A student tries to obtain hydrated magnesium sulfate crystals by evaporating the solution to dryness instead of crystallising it.
Explain, in two points, why this method does not produce hydrated crystals.
Question 4
2 marks · Easy
Answer and see the solution →Explain, using balanced equations, why hydrogen gas is produced when magnesium reacts with dilute sulfuric acid to make magnesium sulfate.
Question 5
3 marks · Easy
Answer and see the solution →The table shows observations during a student's preparation of hydrated copper(II) sulfate from copper(II) oxide and dilute sulfuric acid.
Step Observation Add excess copper(II) oxide to warm acid Black solid remains Filter the mixture Blue solution collected Heat solution until nearly saturated Blue crystals begin to form when cooled (a)[1 mark]What does the black solid remaining in the beaker show about the reaction?
(b)[1 mark]Why is the solution filtered at this stage?
(c)[1 mark]Explain how the appearance of blue crystals shows the solution is nearly saturated.
Question 6
1 mark · Easy
Answer and see the solution →State why crystallisation is used instead of evaporation to dryness when preparing hydrated salts.
Question 7
3 marks · Easy
Answer and see the solution →Hydrated magnesium sulfate crystals can be prepared using magnesium and dilute sulfuric acid.
(a)[1 mark]Write the balanced symbol equation for the reaction.
(b)[1 mark]State the gaseous product formed.
(c)[1 mark]Write the equation for the crystallisation reaction to form hydrated magnesium sulfate.
Question 8
2 marks · Easy
Answer and see the solution →A student uses 50 cm³ of dilute sulfuric acid in a beaker to prepare a soluble salt. Give the two reasons for heating the acid gently in this experiment.