Question

The complex ion havin minimum magnitude of ${\Delta }_0$ (CFSE)is

• A. $\left[Cr\right(CN{)}_6{]}^{3-}$
• B. $\left[Co\right(N{H}_3{)}_6{]}^{3+}$
• C. $\left[Co\right(Cl{)}_6{]}^{3-}$
• D. $\left[Cr\right(H_{2}O{)}_6{]}^{3+}$

Answer 1

The correct option is C

$\left[Co\right(Cl{)}_6{]}^{3-}$

$C{o}^{3+}-d^6$ $\text{low spin}$ ${\Delta }_o=4\times \left(0.4\right)+2(+0.6)=-0.4{\Delta }_o$
$C{S}^{3+}-d^3$ $\text{low spin}$ ${\Delta }_o=4\times \left(0.4\right)=-1.2{\Delta }_o$