Question

Among the following the inner orbital complex is

• A. $[CuC{l}_4{]}^{2-}$
• B. $\left[Ni\right(H_{2}O{)}_6{]}^{2+}$
• C. $\left[Co\right(CN{)}_6{]}^{3-}$
• D. $(NiC{l}_4{)}^{2-}$

Answer 1

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

Inner orbital complexes are coordinate compounds having a central metal atom that undergoes hybridization of atomic orbitals including the inner d orbitals.

$\left[Co\right(CN{)}_6{]}^{3-}$
Oxidation state $\Rightarrow x+6(-1)=-3$
$\Rightarrow x=+3$
$Co\left(27\right)=1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{2}3d^7$$C{N}^{-}$ is a strong field ligand and causes pairing.
$\therefore \left[Co\right(CN{)}_6{]}^{3-}$ is an inner orbital complex and all other complexes are outer orbital complexes. Hence option (c) is correct.