Question

The stabilisation of coordination compounds due to chelation is called the chelate effect. Which of the following is the most stable complex species?

• A. $\left[Fe\right(CO{)}_5]$
• B. $\left[Fe\right(CN{)}_6{]}^{3-}$
• C. $\left[Fe\right(C_2{O}_4{)}_3{]}^{3-}$
• D. $\left[Fe\right(H_{2}O{)}_6{]}^{3+}$

Answer 1

The correct option is C $\left[Fe\right(C_2{O}_4{)}_3{]}^{3-}$

Formation of a cycle by linkage between a metal ion and ligand is known as chelation. Chelation stabilizes the coordinate compound. The ligand which chelates the metal ion are known as chelating ligand. Here, only $\left[Fe\right(C_2{O}_4{)}_3{]}^{3-}$ is a coordination compound which contains oxalate ion as a chelating ligand. Hence, it stabilizes coordinate compound by chelating $F{e}^{3+}$ ion.