Question

The product obtained at anode when $50\%H_{2}S{O}_4$ aqueous solution is electrolysed using platinum electrodes is :

• A. $H_{2}S{O}_3$
• B. $H_2{S}_2{O}_8$
• C. $O_2$
• D. $H_2$

Answer 1

Answer: (B)

$H_2{S}_2{O}_8$

Hydrogen peroxide can be produced by electrolysis of sulfuric acid. At the anode the following reaction takes place:
$H_{2}S{O}_4^{-}\to S_2{O}_8^{2-}+2H^{+}+2e^{-}$
The reaction of this ion with water serves as a commercial preparation of hydrogen peroxide:
$S_2{O}_8^{2-}\left(aq\right)+H_{2}O\to H_2{O}_2\left(aq\right)+2HS{O}_4^{-}$