Question

Which one of the following cyano complexes would exhibit the lowest value of paramagnetic behavior?

• A. $\left[Co\right(CN{)}_6{]}^{3-}$
• B. $\left[Fe\right(CN{)}_6{]}^{3-}$
• C. $\left[Mn\right(CN{)}_6{]}^{3-}$
• D. $\left[Cr\right(CN{)}_6{]}^{3-}$

Answer 1

The correct option is A $\left[Co\right(CN{)}_6{]}^{3-}$

$C{N}^{-}$ is a strong field ligand.


In case of $\left[Co\right(CN{)}_6{]}^{3-}$, there is no unpaired electron. Hence it has lowest value of paramagnetic behaviour.