Question

Which of the following complex is an outer orbital complex?

• A. $\left[Ni\right(N{H}_3{)}_6{]}^{2+}$
• B. $\left[Mn\right(CN{)}_6{]}^{4-}$
• C. $\left[Co\right(N{H}_3{)}_6{]}^{3+}$
• D. $\left[Fe\right(CN{)}_6{]}^{4-}$

Answer 1

Answer: (A)

$\left[Ni\right(N{H}_3{)}_6{]}^{2+}$

The central metal ions in $\left[Ni\right(N{H}_3{)}_6{]}^{2+},\left[Mn\right(CN{)}_6{]}^{4-},\left[Co\right(N{H}_3{)}_6{]}^{3+}and\left[Fe\right(CN)6{]}^{4-}$ 8, 5, 6 and 6 d electrons respectively.

The central metal atom in the complexes $\left[Mn\right(CN{)}_6{]}^{4-},\left[Co\right(N{H}_3{)}_6{]}^{3+}and\left[Fe\right(CN)6{]}^{4-}$ undergoes $d^{2}s{p}^3$ hybridization to form inner orbital or low spin or spin paired complex.

The central metal atom in $\left[Ni\right(N{H}_3{)}_6{]}^{2+}$ undergoes $s{p}^3{d}^2$ hybridization to form outer orbital or high spin or spin paired complex.

Hence the correct option is A.