Question

how long will it take for a 1.5A current to coat evenly a layer of copper 0.1mm thick on both sides of a 12cm by 12cm copper plate(e.c.e of copper is 0.000331gC; density of copper 9gcm?

Answer 1

the volume of Cu deposited is 12*12*0.01 = 1.44 cm^3
Thus, the mass of Cu is 1.44 * 9 = 12.96g
Now, how many moles of Cu is that? How many electrons needed?
See what you can do with that so far...