Question

Explain why kmno4 is a stronger oxidising agent in an acidic medium than in an alkaline medium?

Answer 1

1. The half reaction sin acidic as well as basic medium are as follows:

Acidic Medium:

MnO_​4^- + 8H⁺ + 5e^- $\to$ Mn²⁺ + 4 H₂O

Basic medium:

MnO₄^- + e^- $\to$ MnO₄^2-

2. Change in oxidation states:

In acidic medium: +7 to +2
In basic medium: +7 to +6

3. Thus, we see that in acidic medium Mn reduces more, thus it is a stronger oxidising agent in acidic medium.