In electrolytic deposition, which quantity is directly proportional to the total charge passed through the circuit?

• A. Current
• B. Time
• C. Current × Time
• D. Voltage

Answer: (C)

In electrolytic deposition, how much material gets deposited is governed by the total electric charge that passes through the circuit. This follows Faraday’s law: the deposited amount is proportional to the total charge Q delivered. The total charge is defined as the integral of current over time; when the current is constant, Q = I t. So the quantity that directly tracks the total charge is the product of current and time (I × t), since that product equals the total charge that has flowed. Voltage drives the reaction but does not by itself determine how much material deposits, and current or time alone don’t capture the total charge unless you know the other variable.