Question

In which of the following coordination entities, the magnitude of ${\Delta }_{\circ }$ [CFSE in octahedral field] will be maximum?

• A. $\left[Co\right(CN{)}_6{]}^{3-}$
• B. $\left[Co\right(N{O}_2{)}_6{]}^{3-}$
• C. $[Co{F}_6{]}^{3-}$
• D. $\left[Co\right(N{H}_3{)}_6{]}^{3+}$

Answer 1

The correct option is A

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

In each case, the central metal is $C{o}^{3+}$ and thus the stronger field ligand will effect the higher octahedral Crystal field splitting energy ${\Delta }_{\circ }$.

Hence, the correct answer is:

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