Question

In the complexes $\left[Fe\right(H_{2}O{)}_6{]}^{3+},\left[Fe\right(CN{)}_6{]}^{3-},\left[Fe\right(C_2{O}_4{)}_3{]}^{3-}$ and $[FeC{l}_6{]}^{3-}$ most stable is:

• A. $\left[Fe\right(H_{2}O{)}_6{]}^{3+}$
• B. $\left[Fe\right(CN{)}_6{]}^{3-}$
• C. $\left[Fe\right(C_2{O}_4{)}_3{]}^{3-}$
• D. $[FeC{l}_6{]}^{3-}$

Answer 1

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

Among the given complexes the most stable is $\left[Fe\right(CN{)}_6{]}^{3-}$ because only this complex is forming a inner orbital complex because of the presence of a strong field ligand and its hybridization is $d^{2}s{p}^3$ while rest of the complexes forms a outer orbital complex which are less stable in comparison.