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Assertion (A): The purple colour of KMnO4 arises from a charge-transfer transition. Reason (R): In the MnO4- ion the manganese has no electrons in its d-orbitals. Choose the correct option.

1. (A) if both (A) and (R) are true and (R) is the correct explanation of (A)
2. (B) if both (A) and (R) are true but (R) is not correct explanation of (A)
3. (C) if (A) is true but (R) is false
4. (D) if (A) is false and (R) is true

Correct answer: (A) if both (A) and (R) are true and (R) is the correct explanation of (A)

Solution

In MnO4- the Mn is +7 (d0), so no d-d transition is possible; the intense purple colour is due to O-to-Mn ligand-to-metal charge transfer, making R the correct explanation of A.

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