Question

Copper sulphate soln. is electrolysed using copper electrodes as seen in diagram.

(i) Which electrode to your left or right is known as the oxidising electrode and why?
(ii) Write the equation representing the reaction that occurs.
(iii) State two appropriate observations for the above electrolysis reaction.

August 8, 2024

Answer

(i) The electrode connected to the positive terminal of the battery (i.e., electrode on the left) is the oxidizing electrode as anions donate excess electrons to the anode and are oxidized to neutral atoms.

(ii) Cu – 2e^– ⟶ Cu²⁺

(iii) Copper anode shows a loss in mass. The blue colour of aq. copper sulphate soln. remains unchanged.

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