Question

Neglect overpotential and determine the minimum potential required to electrolyze molten CuCl₂.

---Select--- 0.80 V 1.1 V 1.4 V 1.7 V 2.0 V 2.3 V

How grams of Cu would be deposited and how many liters of Cl₂ gas would be produced at 185 ^oC and 3.20 atm by passing a current of 22.0 A for 12.0 hrs?

What is the average current passing through a solution of NiSO₄ if 3.83 g of Ni were deposited in 5.81 hours?

How many minutes would a solution of Fe³⁺ have to be electrolyzed with a 3.290 A current to plate out 1.58 g of Fe?

Answer 1

1)

Cu ------------> Cu2+ + 2e-

Cl2 + 2e-   ------------> 2 Cl-

potential = Eored + EOoxidation

          = 1.36 + 0.34

          = 1.70 V

2)

current = 22.0 A , time = 12.0 hrs = 43200 sec

W = E x i x t / 96485

    = 31.77 x 22 x 43200 / 96485

   = 312.97 g

mass of Cu deposited = 313 g

moles of Cl2 = 4.924 mol

P V = n R T

3.20 x V = 4.92 x 0.0821 x 458

V = 57.9

volume of Cl2 = 57.9 L

3)

equivalent weight of Ni = 29.35

3.83 = 29.35 x i x 5.81 x 3600 / 96500

i = 0.602 A

current = 0.602 A

4)

time = 41.5 min