WORKSHEET ON CHAP 10- ELECTROLYSIS
1.a. Solid sodium chloride is dissolved in water. The sodium chloride solution is electrolysed in the apparatus
shown in Figure 8.
iii) Molten lead bromide can be electrolysed to form molten lead and bromine gas. Explain how a student could
modify the apparatus shown in Figure 8 to carry out this electrolysis.
(2)
2 (a) This question is about electrolysis. Draw one line from the electrolysis keyword to the correct definition.
(4)
(b) Ionic compounds are capable of being electrolysed under certain conditions.
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
1
WORKSHEET ON CHAP 10- ELECTROLYSIS
Use words from the box to complete the sentences.
(3)
3.a.
b. Describe what you would have to do to lead chloride so it acts as an electrolyte.
Give a reason for your answer
(2)
c. Copper(II) chloride solution is electrolysed.
Write the half equation for the reaction that happens at the anode
(2)
d. Explain why reduction happens at the cathode.
Use the movement of electrons in your answer.
(2)
(Q1-Q3 Edexcel GCSE)
4. a. This question is about copper and its compounds.
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
2
WORKSHEET ON CHAP 10- ELECTROLYSIS
Copper is a metal used for electrical wiring. Explain why copper is a good conductor of electricity.
(2)
b. This apparatus is used to investigate the electrolysis of copper(II) sulfate solution with graphite
electrodes.
Copper forms at the negative electrode and oxygen forms at the positive electrode.
i) State what would be observed at each electrode.
negative electrode .................................................................................................................. positive electrode
....................................................................................................................
(2)
ii) The ionic half‐equation for the reaction at the negative electrode is Cu2+ + 2e– → Cu. State why this is a
reduction reaction
(1)
iii) Explain why the copper(II) sulfate solution becomes paler blue during the electrolysis.
(2)
5.a. A teacher uses this apparatus in a fume cupboard to demonstrate the electrolysis of lead(II) bromide.
The lead(II) bromide is heated until it melts. When the lead(II) bromide melts, the lamp lights. One of the
products of this electrolysis is lead.
i) State why solid lead(II) bromide does not conduct electricity.
(1)
ii) Bromine is formed by the oxidation of bromide ions at the positive electrode. Complete the ionic halfequation for the oxidation of bromide ions.
(1)
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
3
WORKSHEET ON CHAP 10- ELECTROLYSIS
iii. iii) Explain why lead metal forms at the negative electrode.
(2)
iv) The teacher stops heating the mixture and allows it to solidify. Suggest why the lamp stays alight. (1)
6.a. The diagram shows how hydrogen gas and chlorine gas can be prepared in the laboratory by
electrolysis of a concentrated solution of sodium chloride.
i) Give a test for hydrogen gas
(1)
ii) Give a test for chlorine gas.
(2)
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
4
WORKSHEET ON CHAP 10- ELECTROLYSIS
iv) Suggest why the volume of chlorine collected during this electrolysis is less than the volume of
hydrogen collected.
(1)
(c) In the chemical industry, chlorine can be produced by the electrolysis of molten sodium chloride. The
overall equation for this reaction is
2NaCl (l) → 2Na (l) + Cl (g)
Explain why sodium chloride needs to be molten rather than solid for electrolysis to occur.
(2)
7.a. The teacher then sets up a circuit in a fume cupboard using the pure, dry sample of lead(II) bromide.
Explain why the lamp does not light when the lead(II) bromide is solid.
(2)
b. The teacher heats the lead(II) bromide. When the lead(II) bromide is molten, the lamp lights and
bromine forms at the positive electrode.
i) State what observation would be made at the positive electrode.
(1)
ii) Explain how bromide ions in the molten lead(II) bromide become bromine molecules at the positive
electrode.
(4)
c. Write an ionic half-equation for the reaction that occurs at the negative electrode. Include state symbols
in your equation.
(2)
8.a. Describe, in terms of electrons and with the help of suitable equations, what happens during the
electrolysis of molten sodium chloride.
(4)
b. The products of electrolysis of molten sodium chloride are different to those of aqueous sodium chloride.
Explain the different products from the electrolysis of aqueous sodium chloride.
(2)
(Q4 – Q8 Edexcel IGCSE)
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
5
WORKSHEET ON CHAP 10- ELECTROLYSIS
ANSWERS
1.a.
2.
3.
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
6
WORKSHEET ON CHAP 10- ELECTROLYSIS
4.
5.a.
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
7
WORKSHEET ON CHAP 10- ELECTROLYSIS
6.a.
b.
7.
b.
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
8
WORKSHEET ON CHAP 10- ELECTROLYSIS
c.
8.a.
b.
MAQSUDUR RAHMAN
SENIOR PHYSICS AND CHEMISTRY TEACHER
MOB- 01323883243, WHATSAPP- 01914428287
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
9
WORKSHEET ON CHAP 10- ELECTROLYSIS
COPYRIGHT © 2024 MAQSUDUR RAHMAN 01323883243
10