Question

Why is the color of potassium permanganate pink?

Answer 1

Hint: We need to know that the potassium permanganate is in inorganic salt which is pink in color having chemical formula \[KMn{O_4}\].Potassium permanganate is widely used in chemical industry and laboratories as a strong oxidizing agent, and also as a medication for dermatitis and for cleaning wounds.

Complete answer:
We have to know that the color of \[KMn{O_4}\] is due to transitions of charge transfer by the absorption of visible light. Metal ions possess the electron in \[KMn{O_4}\] and thus the transition of charge takes place from \[{O^-}\] to \[M{n^ + }\].Undiluted permanganate potassium has a striking purple tint, but pink should be a diluted solution. Potassium permanganate must be filtered because burns can be caused by an undiluted solution. The color of \[KMn{O_4}\] is due to charge transfer transitions by absorption of visible light. \[KMn{O_4}\] has a deep purple color. The metal ions in \[KMn{O_4}\] contains d electron and, therefore, charge transfer occurs from \[{O^-}\] to \[M{n^ + }\]. In fact, the lowest energy \[L \to M\] charge transfer is due to the transition of a nonbonding 2p oxygen electron to the unoccupied molecular orbital level of a tetrahedral compound. As the positive charge on a metal ion increases, its electro negativity also increases. Therefore, a transfer of charge from \[{O^-}\] to \[M{n^ + }\] ions may occur in the lower energy region (visible region).

Note:
We have to know that the dilute solutions of \[KMn{O_4}\] convert alkenes into diols (glycols). This behavior is also used as a qualitative test for the presence of double or triple bonds in a molecule, since the reaction decolorizes the initially purple permanganate solution and generates a brown precipitate \[\left( {Mn{O_2}} \right)\]. Manganese belongs to the d block element that is a transition metal.