Easy INTEGER +4 / -1 PYQ · JEE Mains 2023

In alkaline medium, the reduction of permanganate anion involves a gain of __________ electrons.

Answer (integer) 3

Solution

<p>In alkaline medium, the reduction of permanganate anion involves a gain of <strong>3 electrons</strong>.</p> <p>The balanced chemical equation for the reduction of permanganate anion in alkaline medium is:</p> $ \begin{equation} \ce{MnO4^{-}(aq) + 3 e^{-} + 2 H2O(l) -> MnO2(s) + 4 OH^{-}(aq)} \end{equation}$<p>In this reaction, the permanganate anion (MnO<sub>4</sub><sup>-</sup>) is reduced to manganese dioxide (MnO<sub>2</sub>) by gaining 3 electrons. The water molecules (H<sub>2</sub>O) are oxidized by losing 2 electrons. The hydroxide ions (OH<sup>-</sup>) are spectator ions that do not participate in the redox reaction.</p> <p>The reduction of permanganate anion in alkaline medium is a useful reaction for a variety of analytical and synthetic purposes. For example, it can be used to quantitatively determine the concentration of an analyte in a solution, or to synthesize a variety of organic compounds.</p>

About this question

Subject: Chemistry · Chapter: Redox Reactions · Topic: Oxidation States

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