Question

State whether given statement is true or false:
An alternating current cannot be used for electroplating.
A. True.
B. False.

Answer 1

Hint: Electroplating is done by sacrificing either one electrode, or an electrolyte in the solution. When connected to a circuit, this electric field will move charges, giving rise to a current, and hence electricity. Applying AC would be charging the battery in one half of the cycle, and discharging it in the other half - the net effect is zero.

Complete answer:
We know in case of alternating current, the direction of current keeps changing every 0.01 a second. Due to changing direction of the current, the metallic ions in the electrolyte keeps shunting between the electrodes that keep changing polarity. Hence AC current cannot be used in electroplating.
Hence the given statement is true.

So, the correct answer is “Option A”.

Note:
In both battery charging and electrolysis, an electric field applied across the electrolytic solution or paste causes a chemical change.
For the battery, the change is reversible, such that when the external electric field is removed, the newly formed chemicals will set up an opposite electric field. Applying AC would be charging the battery in one half of the cycle, and discharging it in the other half - the net effect is zero.
For electrolysis, AC can be used, but it won't achieve the result you want. Electrolysis is usually used to split a compound into two components or elements. We would probably want to collect one or both of these at each electrode in its purest form. With AC, we'll get a mixture of both resultant compounds at both ends!
AC won't work, for the same reason as battery charging above. If the latter, it's possible, but it can cause problems depending on how it’s set up. The best that can happen is both electrodes get electroplated.