In the electrolysis of aqueous sodium chloride solution which of the half cell reaction will occur at anode?

Options

A. `Na^(+) (aq) +e^(-) to Na(s) , E_("Cell")^(Theta) = -2.71V`
B. `2H_(2)O (l) to O_(2) (g) +4H^(+) (aq) +4e, E_("Cell")^(Theta)=1.23V`
C. `H^(+) (aq) +e^(-) to (1)/(2) H_(2) (g) , E_("Cell")^(Theta) =0.00V`
D. `Cl^(-)(aq) to (1)/(2) Cl_(2) (g) +e^(-) , E_("Cell")^(Theta) =1.36V`

Answer

D

Explanation

Oxidation occurs at anode. Oxidation at anode should be favoured in case of reaction (b) because of its higher value of oxidation potential (- 1.23V) as compared to reaction (d) `E_("ox")^(Theta)=-1.36V`. However, reaction (d) is favoured because of overvoltage.