Chemistry - Coordination Chemistry Question with Solution | TestHub

The number of rings formed by a chelating ligand depends on its denticity. Triethylenetetraamine (trien) is a tetradentate ligand, meaning it has four donor atoms. When it coordinates to a central metal ion, it can form three five-membered chelate rings, which is the maximum among the given options.

1. Triphenyl phosphine ($PP{h}_3$): Monodentate, forms 0 rings.

2. Diethylenetriamine (dien): Tridentate, forms 2 rings.

3. Triethylenetetraamine (trien): Tetradentate, forms 3 rings.

4. Acetylacetonate (acac): Bidentate, forms 1 ring.