Chemistry - Coordination Chemistry Question with Solution | TestHub

Statement A is incorrect because carbon monoxide (CO) is a monohapto (${\eta }^1$) ligand that binds through a single carbon atom, meaning both complexes do not consist exclusively of trihapto (${\eta }^3$) ligands.

Statement C is incorrect because a standard terminal carbonyl (CO) ligand always acts as a 2-electron donor via its carbon lone pair, not a 3-electron donor.

Statement B is correct as the transformation involves a change in oxidation states or electron count, making it a classic organometallic redox reaction.

Statement D is correct because transition metal carbonyl complexes inherently involve synergic bonding through $\sigma$-donation and $\pi$-backdonation.