Question

The line notation for the galvanic cell is:

Ni | NiSO4 (aq) || CuCl2 (aq) | Cu

a) write reduction half-reactions for each electrode.

b) what is the standard potential for the cell?

c) what is the equilibrium constant for the cell?

d) if the cell delivers a constant current of 19.0mA for 6.00 hours, how many grams of nickel will be consumed?

Answer 1

a)

Cu⁺²   + 2e^- -------------> Cu reduction half cell

b) E⁰_cell   = E_R - E_L

E⁰_cell   = 0.34 - (-0.25)

E⁰_cell   = 0.59 V

c)  E⁰_cell   = = 0.059 / n logK

0.59 = 0.059 / 2 logKc

20 = logKc

Kc = 1.0 x 10²⁰

d) first calculate the charge

Charge in columbs = current in A x time in s

Charge = 0.019 A x 6 x 60 x 60

charge = 410.4 C

now according to reaction

2 x 96487 C charge consumes 58.7 g Ni

410.4 C charge consumes 410.4 x 58.7 / 2 x 96487 = 24090.48 / 192974 = 0.125 g Ni

answer = 0.125 g Ni