QQuestion
Write the reaction occurring at the cathode in the electrolysis of acidulated water using platinum electrodes. Why is acidulated water instead of pure water used for electrolysis? [1+2]
OR
Write the reactions occurring at cathode and anode in the electrolysis of the aqueous solution of CuSO4 using Cu – electrodes. What is used as anode in refining of impure copper metal by the process of electrolysis? [2+1]
✓Answer
In the electrolysis of acidulated water, the reaction occurring at the cathode (where reduction takes place) is:
2H+ + 2e−→ H2↑
Acidulated Water is Used
- Increased Conductivity: Acidulated water has more ions, improving conductivity compared to pure water.
- Faster Reaction: The presence of H+ ions accelerates hydrogen gas formation at the cathode, making electrolysis more efficient.
OR
Reactions in Electrolysis of CuSO4 with Cu Electrodes
- At the Cathode: Cu2+ + 2e − → Cu (s)
- At the Anode: Cu (s) → Cu2+ + 2e−
In the refining of impure copper, the anode used is made of impure copper metal.
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