Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Inorganic Chemistry
869 practice questions
Topics covered
- The Alkali Metals85 practice questions
- The Halogens86 practice questions
- Gases in the Atmosphere86 practice questions
- Reactivity Series163 practice questions
- Extraction and Uses of Metals128 practice questions
- Acids, Alkalis and Titrations83 practice questions
- Acids, Bases and Salt Preparations156 practice questions
- Chemical Tests68 practice questions
Practice questions
291–300 of 359 · Easy
Question 291
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 292
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 293
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 294
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 295
1 mark · Easy
Answer and see the solution →State why crystallisation is used instead of evaporation to dryness when preparing hydrated salts.
Question 296
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 297
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.
Question 298
1 mark · Easy
Answer and see the solution →Explain why the titration method must be used when preparing sodium salts from an acid and an alkali.
Question 299
3 marks · Easy
Answer and see the solution →A student wants to prepare pure potassium chloride crystals from potassium hydroxide solution and hydrochloric acid using titration.
(a)[1 mark]State the first step the student should carry out before adding acid.
(b)[1 mark]Describe how the student should use an indicator to find the endpoint of the reaction.
(c)[1 mark]Once the volumes have been determined, explain what the student must do to obtain pure potassium chloride crystals.
Question 300
2 marks · Easy
Answer and see the solution →Explain the role of methyl orange indicator in an acid–alkali titration to prepare potassium salts. Why does the indicator colour change at the endpoint? (2 marks)