Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Chapter
Electrolysis
198 practice questions
Topics covered
- Why things conduct electricity17 practice questions
- Passing electricity through compounds: electrolysis20 practice questions
- The electrolysis of molten compounds19 practice questions
- Electrolysis and redox19 practice questions
- The electrolysis of other molten substances19 practice questions
- The electrolysis of aqueous solutions18 practice questions
- The electrolysis of sodium chloride solution19 practice questions
- The electrolysis of copper(ii) sulfate solution using inert electrodes18 practice questions
- The electrolysis of some other solutions using inert electrodes19 practice questions
- What would happen with non-electrolytes?19 practice questions
Practice questions
11–20 of 198
Question 11
4 marks · Normal
Answer and see the solution →(a)[2 marks]The table shows the results from testing four substances for electrical conductivity:
Substance State Conducts electricity? Potassium bromide Solid No Potassium bromide Molten Yes Glucose Solution in water No Potassium bromide Solution in water Yes Use the data to identify the substance(s) that conduct electricity and describe the conditions in which conduction occurs.
(b)[2 marks]Suggest a reason why potassium bromide conducts electricity in its molten state and in aqueous solution, but not as a solid.
Question 12
1 mark · Normal
Answer and check →Which statement best explains why sodium chloride solution conducts electricity?
- A.It contains ions that are free to move.
- B.It contains free electrons that carry charge.
- C.It contains molecules that can move around.
- D.It contains atoms that are free to move.
Question 13
4 marks · Normal
Answer and see the solution →(a)[2 marks]Explain why molten zinc chloride can conduct electricity but solid zinc chloride cannot.
(b)[2 marks]Describe what must be present in a substance for it to conduct electricity.
Question 14
2 marks · Normal
Answer and see the solution →Explain why solid sodium chloride does not conduct electricity, but molten sodium chloride does.
Question 15
2 marks · Hard
Answer and see the solution →Explain why pure, solid silver chloride does not conduct electricity, but when dissolved in water, it does.
Question 16
5 marks · Hard
Answer and see the solution →A teacher tests the electrical conductivity of four substances in different states. The results are shown in the table below.
Conductivity of substances in different states Substance State Conducts electricity? Potassium nitrate Solid No Potassium nitrate Aqueous Yes Sulfur dioxide Liquid No Lead(II) bromide Molten Yes (a)[1 mark]Identify which of the substances in the table are ionic compounds.
(b)[2 marks]Explain why potassium nitrate conducts electricity when dissolved in water but not as a solid.
(c)[2 marks]Suggest why sulfur dioxide does not conduct electricity, even when liquid. Use your knowledge of bonding.
Question 17
2 marks · Hard
Answer and see the solution →Explain, with reference to structure and particles, why molten lead(II) bromide can conduct electricity.
Question 18
1 mark · Easy
Answer and see the solution →State the name of the liquid or solution that undergoes electrolysis and contains ions.
Question 19
3 marks · Easy
Answer and see the solution →The diagram shows an apparatus for electrolysis.
(a)[1 mark]Name the positively charged electrode.
(b)[1 mark]Name the negatively charged electrode.
(c)[1 mark]Give the term for the solution or molten compound that contains ions in this process.
Question 20
2 marks · Easy
Answer and see the solution →How many positive ions and how many negative ions are present in the formula unit of magnesium bromide ()? State the name for each type of ion.