question_answer 30)

A solution of Ni(NO3)2 is electrolysed between platinum electrodes using a current of 5 amperes for 20 minutes. What mass of Ni is deposited at the cathode?

Answer:

The electrolysis of Ni(NO3)2 may be represented as : Ni(NO3)2   Ni2+ +   or Ni2+ + 2e?   Ni 2 mole           1 mole       F (2 x 96500 C) Quantity of electricity passed = Current in amperes (I) x time in second (t)       or Q = It = 5 x 20 x 60 = 6000C [ t = 20 x 60 sec.]  2 x 96500 C of electricity deposit Ni = 58.5 g  6000 C of electricity deposit Ni