Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
831–840 of 991
Question 831
2 marks · Hard
Answer and see the solution →Write the half-equation for the reaction at the anode during the electrolysis of molten cadmium(II) iodide ( ).
Explain why this reaction is classified as oxidation.
Question 832
1 mark · Easy
Answer and see the solution →State what is meant by: reduction, in terms of electron transfer.
Question 833
3 marks · Easy
Answer and see the solution →The diagram shows the essential parts of an apparatus for the electrolysis of molten magnesium chloride (MgCl).
(a)[1 mark]What does it mean to 'discharge' a chloride ion (Cl) at the electrode?
(b)[1 mark]State what happens to the charge of a chloride ion when it is discharged.
(c)[1 mark]Describe briefly what is formed when chloride ions are discharged at the anode.
Question 834
2 marks · Easy
Answer and see the solution →During the electrolysis of molten sodium iodide (NaI), the following half-equations occur:
For each electrode, state whether the reaction is oxidation or reduction.
(a)[1 mark]Reaction at the anode:
(b)[1 mark]Reaction at the cathode:
Question 835
2 marks · Easy
Answer and see the solution →Explain how the OILRIG mnemonic helps you decide whether a process is oxidation or reduction, using the example of an ion gaining electrons.
Question 836
3 marks · Easy
Answer and see the solution →Table 1 shows the electron profiles for three different reactions.
Table 1: Electron Transfer in Different Reactions Process Type of Particle Electron Change W Iron(III) ion gains 3 electrons X Chloride ion loses 1 electron Y Copper(II) ion gains 2 electrons (a)[1 mark]Identify the process (W, X or Y) that involves oxidation.
(b)[1 mark]State what reduction means in terms of electron transfer.
(c)[1 mark]Identify all processes (W, X or Y) that involve reduction.
Question 837
1 mark · Easy
Answer and see the solution →When an ion is 'discharged' during electrolysis, what happens to its electric charge?
Question 838
3 marks · Easy
Answer and see the solution →During the electrolysis of molten copper(II) bromide (CuBr), the following reactions occur:
(a)[1 mark]Write the half-equation for the reaction at the anode.
(b)[1 mark]State whether the anode reaction is oxidation or reduction.
(c)[1 mark]Explain your answer to (b) using electron transfer.
Question 839
2 marks · Easy
Answer and see the solution →An aluminium ion (Al) gains 3 electrons during electrolysis.
(a)[1 mark]State whether this process is oxidation or reduction.
(b)[1 mark]Explain your answer using the OILRIG mnemonic.
Question 840
2 marks · Normal
Answer and see the solution →State what is meant by:
(a)[1 mark]oxidation, in terms of electron transfer.
(b)[1 mark]reduction, in terms of electron transfer.