Question

3. What mass of copper could be deposited from a copper(II) Sulphate solution using a current of 5.0 A over 100 seconds? ( F =96,500C,Charge of Cu in CuSO4 = +2)​

Answer 1

Mass of copper : 0.165 g

Further explanation

Given

5.0 A over 100 seconds

Required

Mass of copper

Solution

Faraday's law:

The mass of the substance formed at each electrode is proportional to the electric current flowing in the electrolysis

$\tt W=\dfrac{e.i.t}{96500}$

e = Ar / valence = eqivalent weight

i = current

t = time

W = weight

CuSO₄ ----> Cu²⁺ + SO₄²⁻

Cu ----> Cu²⁺ + 2e

e = Ar/2

= 63,5/2 = 31,75

$\tt W=\dfrac{31.75\times 5\times 100}{96500}=0.165~g$