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
71–80 of 156
Question 71
4 marks · Normal
Answer and see the solution →The table below shows the solubility of different ionic compounds in water:
Solubility of Various Ionic Compounds in Water Compound Solubility Potassium nitrate Soluble Sodium chloride Soluble Calcium sulfate Almost insoluble Lead(II) chloride Insoluble Ammonium carbonate Soluble Copper(II) hydroxide Insoluble (a)[1 mark]Name one compound from the table that is insoluble in water.
(b)[1 mark]State the general rule for the solubility of nitrates.
(c)[2 marks]Identify a compound from the table that would be suitable for making a salt by precipitation, and explain your choice.
Question 72
2 marks · Normal
Answer and see the solution →State the solubility rules for (i) all chlorides, and (ii) all hydroxides, in water.
Question 73
2 marks · Hard
Answer and see the solution →State two exceptions to the general solubility of chlorides in water. For each exception, name the insoluble chloride.
Question 74
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 75
2 marks · Hard
Answer and see the solution →State the general solubility rules for carbonates and hydroxides of common metals in water.
Question 76
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 77
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 78
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 79
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 80
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.