Electroloysis. tpack at kibasila sec school

LESSON PLAN

• The topic will be ionic theory and electrolysis• The Sub topic is electrolysis of copper (ii) sulphate

solution using carbon electrodes.• Presentation: the power point show will cover the

concept of formation of ions in copper (ii) sulphate solution, formation of copper deposits on cathode and evolution of hydrogen gas from the anode.

• The copper deposits will be accompanied with the red coat on the surface of cathode where as the oxygen gas by formation of bubbles from surface of anode.

Students activity

• Students will be arranged in a group of three or four.

• They will be provided with relevant materials to carry out experiment at the end of demonstration.

• They will be argued to observe and prove the previous demonstrated phenomena

Class activity• Student will carry out an experiment.• In a group of four they will have to arrange the

apparatus as shown in the diagram• Connect the cells with the electrodes• Immerse the electrodes in the solution• Connect the switch.• Observe what happens at the electrodes and

compare with the demonstration in the animation• Explain it in relation to what they see in the

slides presentation

Electrolysis of Copper(ii)Sulphate solution

using carbon electrodes • Apparatus needed

-Beaker– Carbon electrodes– Copper(ii)Sulphate solution– Switch– Battery and wire

Copper (ii) Sulphate solution

Ions present

Ions present by equations

• CuSO4 (aq) -------------> Cu2+ (aq) + SO4

2- (aq)

• H2O (l) --------------> H+ (aq) + OH-

(aq)

Apparatus set up

DC SOURCE

ANODE

CATHODE

Complete Electrolytic Cell

Migration of Ions

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Conclusion

Copper depositedOxygen gas evolved

Conclusion

• Discuss your results with the help of equations

• Explain the reaction at the cathode

• Explain the reaction at the anode

• What are your conclusions?

• What have you understood about electrolysis?