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

Options

A. `[Fe(CO)_5]`
B. `[Fe(CN)_6]^(3-)`
C. `[Fe(C_2O_4)_3]^(3-)`
D. `[Fe(H_2O)_6]^(3+)`

Answer

C

Explanation

Chelation (formation of cycle by linkage between metal ion and ligand) stabilises the coordination compound. The ligand which chelates the metal ion are known as chelating ligand.
Here, only `[Fe(C_2O_4)_3]^(3-)` is a coordination compound which contains oxalate ion as a chelating ligand. Hence, it stabilises coordination compound by chelating `Fe^(3+)` ion.