Why does the solution decolorize on standing after the equivalence point has been reached?

The potassium permanganate slowly fades in color as it is dissolved in the water.

Explanation:

Hello,

Perhaps, your talking about a titration that was carried out by using potassium permanganate as the titrant, thus, bringing to bear the fact that the equivalence point of a titration is equal to its stoichiometric equivalents of analyte and titrant, one could state that as the titration is carried out, the potassium permanganate slowly fades in color as it is dissolved in the water after the equivalence point is reached since the formed species become colorless as well.

Best regards.