Question

During electrolysis of aqueous copper (II) sulphate using copper electrodes a current of 0.2 amperes was passed through the cell for 5 hours. Determine the change in mass of the cathode that occurred as a result of the electrolysis process. (Cu = 64, IF = 96500 coulombs).

Answer 1

Q = It
= 0.2 x 5 x 60 x 60
= 360ºC
Cu2+ + 2e- Cu
64g→ 2 x 9650ºC
y →36ºC
y = 36º x 64 = 1.194g
2 x 9650º
The cathode increased in mass by 1.194g.