In galvanization, a protective zinc coating is applied to steel or iron. The pro
ID: 991816 • Letter: I
Question
In galvanization, a protective zinc coating is applied to steel or iron. The process for making the molten zinc used for galvanization is complex, but we will consider a simplified version for this problem: In order to prepare the zinc metal for galvanization, electrolysis is performed on an aqueous ZnSO4 solution, causing zinc metal to deposit at the cathode and oxygen to form at the anode.
What is the minimum voltage required to drive this reaction under standard conditions?
If you wish to produce 1.0 kg of zinc metal from an aqueous ZnSO4 solution, how long would you need to run a cell with a current of 3,000 A?
Explanation / Answer
from faraday first law
w = zit
z = E/F
E = equivalent weight of Zn = 65.38/2 = 32.69 g/eq
1000 = (32.69/96500)*3000*t
t = 984 sec = 16.4 min