# Exercise 3 | Electrochemistry

How many hours would be required for the electroplating of 50.0 g of platinum from a solution of [PtCl6]2-, using an average current of 8.50 A at an 80.0 % electrode efficiency?

Faraday’s law of electrolysis:

m = $\frac{\mathrm{It}}{\mathrm{F}}$ x $\frac{\mathrm{M}}{{\mathrm{\nu }}_{\mathrm{e}}}$ x η

m = mass deposited as Pt (in g)
I = current (in A)
t = time (in s)
F = Faraday’s constant = 96485 C.mol-1
M = molar mass (in g.mol-1) ⇒ MPt = 195.1 g.mol-1
νe = stoichiometric coefficient of the electrons in the half reaction equation
η = electrode efficiency

Half reaction: Pt4+ (aq) + 4 e- → Pt (s)      [νe = 4]

t =

t =

t = 4.04 hours