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Question
Why is AC current used instead of DC in measuring the electrolytic conductance?
Solution
1. AC current to prevent electrolysis of the solution.
2. If we apply DC current to the cell the positive ions will be attracted to the negative plate and the negative ions to the positive plate. This will cause the composition of the electrolyte to change while measuring the equivalent conductance.
3. So DC current through the conductivity cell will lead to the electrolysis of the solution taken in the cell. To avoid such electrolysis, we have to use AC current for measuring equivalent conductance.
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