How much current is needed to pass for 1 sec for depositing a metal with a mass equal to double of its electrochemical equivalent?

2 amp

The correct answer is Option (2) → 2 amp

According to Faraday’s first Law of Electrolysis: 

The amount of chemical reaction which occurs at any electrode during electrolysis by a current is proportional to the quantity of electricity passed through the electrolyte (solution or melt).

 m = Zit 

where, m = mass of substance deposited

Z = electrochemical equivalent 

I = current in ampere

t = time in secs 

To deposit a metal with mass equal to double of its electrochemical equivalent,

it is given 

m = 2 × Z 

t = 1 sec 

substituting these values in equation

 m = Zit

 2 × Z = Z × I × 1

Solving this we get, I (current needed) = 2 amp