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a)The set up below was used during electrolysis of aqueous copper (II) sulphate using inert electrodes.

a)The set up below was used during electrolysis of aqueous copper (II) sulphate using inert electrodes.

i) Name a suitable pair of electrodes for this experiment.
ii) Identify the ions and cations in the solution.
iii) On the diagram label the cathode.
iv) Write ionic equations for the reactions that took place at the anode
v) Explain the change that occurred to the Copper (II) Sulphate solution during the experiment.
vi) During the electrolysis a current of 2 amperes was passed through the solution for 4 hours. Calculate the volume of the gas produced at the anode. (1 Faraday = 96500 coulombs and volume of gas at room temperature is 24000cm₃ )
b) i) Draw a diagram to show how an impure copper lump can be refined through electrolysis.
ii) State one other use of electrolysis other than the one shown in b (ii) above.

Answers

(a) (i) Platinum/Graphite (Carbon) Any

(v) The concentration of copper (II) ions in solution decreases and the blue colour of the Copper (II)
Sulphate solution becomes pale and finally colourless.

(ii) – Electroplating
- Extraction of reactive metals
- Cathodic protection

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sharon kalunda answered the question on March 19, 2019 at 13:44

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