Q. On the basis of electrochemical theory of aqueous corrosion, the reaction occurring at the cathode is
A) $O_{2}(g) + 4H^{+}(aq) + 4e^{-} \rightarrow 2H_{2}O(l)$
B) $H_{2}(g) + 2{OH}^{-}(aq) \rightarrow 2H_{2}O(l) + 2e^{-}$
C) $Fe(s) \rightarrow {Fe}^{2 +}(aq) + 2e^{-}$
D) ${Fe}^{2 +}(aq) \rightarrow {Fe}^{3 +}(aq) + e^{-}$
Explanation
(a)
At cathode $2H^{+}(aq) + 2e^{-} \rightarrow 2H$
$2H + \frac{1}{2}\ O_{2} \rightarrow H_{2}O$
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$2H^{+} + \frac{1}{2}O_{2} + 2e^{-} \rightarrow H_{2}O$
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Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.