Question

Which of the following does not evolve oxygen at anode when the electrolysis is carried out of:

• A. Dilute $H_{2}S{O}_4$ with $Pt$ electrodes
• B. Fused sodium hydroxide with $Pt$ electrodes
• C. Acidic water with $Pt$ electrodes
• D. Dilute sulphuric acid using $Cu$ electrodes

Answer 1

The correct option is D Dilute sulphuric acid using $Cu$ electrodes

$E_{ox}^{\ominus }$ of $Cu$ =$-0.34$
Using copper electrodes, copper will oxidize :
$Cu\to C{u}^{2+}+2e^{-}$
So oxygen is not evolved.