Which of the following is the most stable species?
Answer & explanation
Correct answer: option 3
[Fe(C2O4)3]3- is the most stable among the given complexes as it contains three bidentate ligands (C2O42-: oxalato) forming rings giving chelate effect.
Other complexes contain monodentate ligands such as NH3, CN–, H2O. Monodentate ligands does not provide chelate effect.