3.15     A solution of  Ni(No_{3})_{2}is electrolysed between platinum electrodes using a current of 5 amperes for 20  minutes. What mass of Ni is deposited at the cathode?

Answers (1)

We are given: 

                          I  =  5A 

and                    t  =  20(60)  = 1200 sec.

So total charge =  5(1200)  =  6000 C.

The equation for nickel deposition will be:- 

                                 Ni^{+2}\ +\ 2e^-\ \rightarrow\ Ni

Thus, from 2F charge 58.7 g of nickel deposition takes place.

i.e.,                    2(96487)\ C \rightarrow 58.7\ g\ Ni   

So for 6000 C charge total nickel deposition will be:- 

                                       = \frac{58.7}{2\times96487}\times6000

or                                    = 1.825\ g

Hence 1.825 g Ni will be deposited in the given conditions.