Ncert Exercises & Solutions

3.14 How much electricity is required in coulomb for the oxidation of

(i) 1 mol of H₂O to O₂?

(ii) 1 mol of FeO to Fe₂O₃?

Hint: Use Faraday’s Laws of Electrolysis

(i) According to the question,

H_{2} O \to H_{2} + \frac{1}{2} O_{2}

Now, we can write:

O^{2 -} \to \frac{1}{2} O_{2} + 2 e^{-}

Electricity required for the oxidation of 1 mol of

H_{2} O

O_{2}

=2 F

= 2 x 96487 C

= 192974 C

(ii) According to the question,

{Fe}^{2 +} \to {Fe}^{3 +} + e^{- 1}

Electricity required for the oxidation of 1 mol of FeO to

{Fe}_{2} O_{3}

= 1 F

=96487 C