Statement 1 : Permanganate titrations in presence of hydrochloric acid are unsatisfactory.
Statement 2: Hydrochloric acid is oxidized to chlorine by MnO₄⁻.

Question

Statement 1 : Permanganate titrations in presence of hydrochloric acid are unsatisfactory. Statement 2: Hydrochloric acid is oxidized to chlorine by MnO₄⁻.

TestHub · Accepted Answer

Statement 1 is true because MnO₄⁻ is a strong oxidizing agent. Statement 2 is also true and correctly explains Statement 1. MnO₄⁻ oxidizes Cl⁻ ions from HCl to Cl₂ gas, consuming the permanganate and leading to inaccurate titration results.

The relevant half-reactions are:

Oxidation: $2 C l^{-} (a q) \to C l_{2} (g) + 2 e^{-}$

Reduction: $M n O_{4}^{-} (a q) + 8 H^{+} (a q) + 5 e^{-} \to M n^{2 +} (a q) + 4 H_{2} O (l)$

Chemistry - Redox Reactions Question with Solution | TestHub

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