Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
The electrolysis of other molten substances
19 practice questions
Practice questions
1–8 of 8 · Easy
Question 1
1 mark · Easy
Answer and see the solution →State which element forms at the anode during the electrolysis of molten magnesium oxide.
Question 2
3 marks · Easy
Answer and see the solution →The electrolysis of molten zinc(II) chloride produces two substances at the electrodes.
(a)[1 mark]Write the ionic half-equation for the reaction at the cathode.
(b)[1 mark]Write the ionic half-equation for the reaction at the anode.
(c)[1 mark]State which type of particle (cation or anion) moves towards the cathode.
Question 3
2 marks · Easy
Answer and see the solution →Balance the following ionic half-equation for the electrolysis of molten calcium chloride so that both atoms and charges balance:
Question 4
2 marks · Easy
Answer and see the solution →Explain why sodium, and not chlorine, is formed at the cathode during the electrolysis of molten sodium chloride.
Question 5
3 marks · Easy
Answer and see the solution →A student studies the electrolysis of three molten ionic compounds.
Results of Electrolysis Compound Element at Cathode Element at Anode Magnesium fluoride ? Fluorine Lead(II) bromide Lead ? Potassium iodide ? Iodine (a)[1 mark]Complete the table by naming the element formed at the cathode for magnesium fluoride.
(b)[1 mark]Name the element formed at the anode for lead(II) bromide.
(c)[1 mark]Name the element formed at the cathode for potassium iodide.
Question 6
1 mark · Easy
Answer and see the solution →How many electrons are required to balance the following ionic half-equation for the reduction of potassium ions during the electrolysis of molten potassium chloride?
Question 7
3 marks · Easy
Answer and see the solution →This question is about the electrolysis of molten lithium bromide.
(a)[1 mark]Name the particle that moves towards the anode.
(b)[1 mark]State the element formed at the cathode.
(c)[1 mark]Explain, using ions, how you know which element forms at the cathode.
Question 8
2 marks · Easy
Answer and see the solution →Write the balanced ionic half-equation for oxygen formation at the anode during the electrolysis of molten aluminium oxide.