Which one of the following ions exhibits d-d transition and paramagnetism as well? (NEET 2018) (a) 2- Cr O (b) - MnO (c) 2- CrO (d) 2- MnO

2- 4 MnO exhibits d-d transition and as it has one unpaired electron therefore it is paramagnetic. Mn atom in 2- 4 MnO has +6 oxidation and has outer electronic configuration 1 3d . Mn atom has outer electronic configuration 5 2 3d 4s . Mn atom in 4 MnO has +7 oxidation and has outer electronic configuration 0 3d . It has zero unpaired electrons and is therefore diamagnetic, d-d transitions are not possible. Cr atom in 2- 4 CrO has +6 oxidation and has outer electronic configuration 0 3d . It has 0 unpaired electrons and is therefore diamagnetic, d-d transitions are not possible. Cr atom h