Suppose you need to produce 25.0 g of pure copper by electrolysis of a solution of cuso, (aq), by the reduction, cu2+ (aq) + 2 e- + cu(s). how much time will it take with a current of 3.00 a? coulombs amps x seconds. faraday's constant is 9.65 x 104 c/(mol e-) and the molecular weight of cu is 63.5 g/mol