What mass of nickel could be electroplated from a solution of nickel(II) chloride by a current of 0.480 A flowing for 12 hours?

Question

| General Chemistry 3

Accepted Answer

Faraday’s law of electrolysis:

m = $\frac{It}{F}$ x $\frac{M}{ν_{e}}$

m = mass deposited as Ni (in g)
I = current (in A)
t = time (in s) ⇒ 12 hours = 4.32 x 10⁴ s
F = Faraday’s constant = 96485 C.mol^-1
M = molar mass (in g.mol^-1) ⇒ M_NiCl2 = 129.6 g.mol^-1
ν_e = stoichiometric coefficient of the electrons in the half reaction equation

Half reaction: Ni²⁺ (aq) + 2 e^- → Ni (s) [ν_e = 2]

m =

\frac{It}{F}

x

\frac{M}{ν_{e}}

m =

\frac{0.48 \times 4.32 \times 10^{4}}{96485} \times \frac{129.6}{2}

m = 6.31 g of NiCl₂

Exercise 2 | Electrochemistry

General Chemistry 3 - Exercise 2