Question

A (Light pink colour complex) $\underset{\Delta }{\stackrel{P{b}_3{O}_4/dil.HN{O}_3}{\to }}HMn{O}_4\stackrel{H_{2}S/H^{+}}{\to }A$ (Light pink colour complex).
Calculate $CFSE$ value in light pink colour complex.

Answer 1

$\Rightarrow$ Pink coloured complex: $\left[Mn\right(H_{2}O{)}_6{]}^{2+}$
$M{n}^{2+}\left(3d^5\right)$ in $\left[Mn\right(H_{2}O{)}_6{]}^{++},{\Delta }_o<P$
CFSE of the pink coloured complex:
$=3\times (-\frac{2}{5}{\Delta }_c)+2\times \left[\frac{3}{5}{\Delta }_o\right]=0$