Question

$KMn{{O}_ {4}} $ in acidic medium is always reduced to $M{{n}^ {2+}} $.
(a) true
(b) false

Answer 1

Hint: Acidic medium is also termed as acid catalyzation. Some reactions such as esterification, aldol condensation etc. become spontaneous when catalysed under specific acids. These acids oxidized the reactant for completion of reaction.

Complete step by step answer:
We have been provided $KMn{{O}_ {4}} $,
Potassium permanganate is an inorganic compound with the chemical formula $KMn{{O}_ {4}} $ and composed of ${{K}^ {+}} $and$Mn{{O}_ {4}} ^ {-} $. It is a purplish-black crystalline solid that dissolves in water to give intensely pink or purple solutions.
The oxidizing effect of $KMn{{O}_ {4}} $ is maximum in acidic medium and least in basic medium as in acidic medium the reduction in oxidation state of Mn is max while it is the least in basic medium. Hence, acidic medium is used when you want strong oxidation and basic when very mild oxidation is required.
In acidic solution, $KMn{{O}_ {4}} (Mn{{O}_ {4}} ^ {-}) $gets reduced to the colourless $M{{n}^ {2+}} $ion:
     \[8{{H}^ {+}} +Mn{{O}_ {4}} ^ {-} +5{{e}^ {-}} \to M{{n}^ {2+}} +4{{H}_ {2}} O\]

$KMn{{O}_ {4}} $ is a strong oxidizing agent with Mn in +7 state. In acidic medium there is a change of 5 electrons whereas in neutral and basic medium it will act as an oxidising agent.
So, we can say that $KMn{{O}_ {4}} $ in acidic medium is always reduced to $M{{n}^ {2+}} $.
So, the correct answer is “Option A”.

Note: Potassium permanganate is used as a wet dressing for wounds on your skin's surface that are blistered or oozing pus. Athlete's foot and impetigo. Potassium permanganate can help to treat both bacterial and fungal skin infections such as athlete's foot and impetigo.