Question

Amongst the following, the total number of species which are diamagnetic is _______.
$K_{4}\left[Fe \left(CN\right)_{6}\right],K_{3}\left[Cr \left(CN\right)_{6}\right],K_{3}\left[Co \left(CN\right)_{6}\right],$ $K_{2}\left[Ni \left(CN\right)_{4}\right],\left(\left[Co \left(\left(NH\right)_{3}\right)_{6}\right]\right)^{3 +},K_{2}\left[\left(TiF\right)_{6}\right],\left(\left[Pt \left(\left(NH\right)_{3}\right)_{4}\right]\right)^{2 +}$

Answer 1

$\left(\left[Fe \left(CN\right)_{6}\right]\right)^{4 -},\left(\left[Co \left(CN\right)_{6}\right]\right)^{3 -}$
$\left(\left[Ni \left(CN\right)_{4}\right]\right)^{2 -},\left(\left[Co \left(\left(NH\right)_{3}\right)_{6}\right]\right)^{3 +},\left(\left[\left(TiF\right)_{6}\right]\right)^{2 -}$
$\left(\left[Pt \left(\left(NH\right)_{3}\right)_{4}\right]\right)^{2 +}$ all are diamagnetic due to absence of unpaired electrons.
$K_{4}\left[Fe \left(CN\right)_{6}\right]hast_{2 g}^{6},e_{g }^{0}configuration,K_{3}\left[Cr \left(CN\right)_{6}\right]hast_{2 g}^{3},e_{g }^{0}configuration,K_{3}\left[Co \left(CN\right)_{6}\right]hast_{2 g}^{6},e_{g }^{0}configuration.Similarly,K_{2}\left[Ni \left(CN\right)_{4}\right]has\left(dsp\right)^{2}hybridisation,\left(\left[Co \left(\left(NH\right)_{3}\right)_{6}\right]\right)^{3 +}hast_{2 g}^{6},e_{g }^{0}configuration,K_{2}\left[\left(TiF\right)_{6}\right]hasd^{0}configurationand\left(\left[Pt \left(\left(NH\right)_{3}\right)_{4}\right]\right)^{2 +}is\left(dsp\right)^{2}hybridised.$