Question

How many molecules of chlorine should be deposited from molten sodium chloride in one minute by a current of 300 milliamperes?

Answer 1

The electrolysis of the chlorine will takes place as follows :
Cl ^- + 1e ^- → 1/2 Cl₂
Amount of Cl₂ gas released; w = E It /F
I = 300 x 10^-3 A
t = 60 s
F = 96500(for transfer of 1e^-)
E = 35.5 g
w = 35.5 g x ​300 x 10^-3 A x 60 s / 96500
= 0.0066 g
Molar mass of Cl₂ = 71 g
Moles of Cl₂ deposited = 0.0066/71 g
= 9.32 x 10^-5 moles
Molecules of Cl₂ deposited = moles of Chlorine x N_A
= 9.32 x 10^-5 x 6.022 x 10²³
= 5.61 x 10¹⁹