These are the options for the question :. KMnO4 is coloured due to:
a. d-d transitions
b. charge transfer from ligand to metal
c. unpaired electrons in d orbital of Mn
d. charge transfer from metal to ligand
The correct answer is -b. charge transfer from ligand to metal
The Mn atom in KMnO4 has +7 oxidation state with electron configuration
[Ar]3d 04s0 Since no unpaired electrons are present, d−d transitions are not
possible. The molecule should, therefore, be colourless.
Its intense purple due to L→M (ligand to metal) charge transfer 2p(L) of O to
3d(M) of Mn.
