JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
Given below are two statements: Statement \((I)\) : Fusion of \(\mathrm{MnO}_2\) with \(\mathrm{KOH}\) and an oxidising agent gives dark green \(\mathrm{K}_2 \mathrm{MnO}_4\). Statement \((II)\) : Manganate ion on electrolytic oxidation in alkaline medium gives permanganate ion. In the light of the above statements, choose the correct answer from the options given below.
- A Both Statement \(I\) and Statement \(II\) is true
- B Both Statement \(I\) and Statement \(II\) is false
- C Statement \(I\) is true but Statement \(II\) is false
- D Statement \(I\) is false but Statement \(II\) is true
Answer & Solution
Correct Answer
(A) Both Statement \(I\) and Statement \(II\) is true
Step-by-step Solution
Detailed explanation
\(\mathrm{MnO}_2+4 \mathrm{KOH}+\mathrm{O}_2 \xrightarrow{\text { fused }} 2 \mathrm{~K}_2 \mathrm{MnO}_4+2 \mathrm{H}_2 \mathrm{O}\) Dark green Electrolytic oxidation in alkaline medium : At anode : \(\mathrm{MnO}_4^{2-} \rightarrow \mathrm{MnO}_4^{-}+\mathrm{e}^{-}\)
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