Question

The cathodic reaction in electrolysis of dilute $H_{2}S{O}_4$ with platinum electrode is:

• A. oxidation
• B. reduction
• C. both oxidation and reduction
• D. neutralization

Answer 1

The correct option is B reduction

$Pt$ electrodes are inert. They won't play any part in the reaction at either electrodes. Dil-$H_2{SO}_4$ implies that both $H_2{SO}_4$ and $H_{2}O$ are involved in the electrolyte. $H^{+}$ from $H_2{SO}_4$ and $H^{+}$ from $H_{2}O$ will be attracted to the cathode.

${2H}^{+}+{2e}^{-}\to H_2$

This is a gain of electrons and so, the reaction is reduction.

$\Rightarrow$ Cathodic reaction in electrolytes of dil.$H_2{SO}_4$ with $Pt$ electrodes is reduction.

Option B is correct.