Easy MCQ +4 / -1 PYQ · JEE Mains 2025

Preparation of potassium permanganate from $\mathrm{MnO}_2$ involves two step process in which the 1st step is a reaction with KOH and $\mathrm{KNO}_3$ to produce

  1. A $\mathrm{K}_3 \mathrm{MnO}_4$
  2. B $\mathrm{K}_4\left[\mathrm{Mn}(\mathrm{OH})_6\right]$
  3. C $\mathrm{K}_2 \mathrm{MnO}_4$ Correct answer
  4. D $\mathrm{KMnO}_4$

Solution

<p>The preparation of potassium permanganate ($\mathrm{KMnO}_4$) from manganese dioxide ($\mathrm{MnO}_2$) involves a two-step process. In the first step, $\mathrm{MnO}_2$ reacts with potassium hydroxide ($\mathrm{KOH}$) and potassium nitrate ($\mathrm{KNO}_3$) under heating. This reaction produces potassium manganate ($\mathrm{K}_2 \mathrm{MnO}_4$) as an intermediate product. The reaction can be depicted as follows:</p> <p>$ \mathrm{MnO}_2 \xrightarrow[\mathrm{KNO}_3, \mathrm{\Delta}]{\mathrm{KOH}} \mathrm{K}_2 \mathrm{MnO}_4 $</p>

About this question

Subject: Chemistry · Chapter: d and f Block Elements · Topic: Properties of Transition Metals

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