Question

a) What is a ligand?

b) Distinguish between a monodentate ligand and bidentate ligand.

Answer 1

In coordination chemistry, ligand is an ion or a molecule that binds to the central metal atom forming coordination complex. The bonding between the ligand and the metal atom or ion is called coordination bond. Here, the ligand donates the electrons to metal atom for the bond formation.

Monodentate ligand is the one which can donate only one pair of electrons to the central metal atom. F-, Cl-, CN- etc..

Bidentate ligand is the one which can donate two pairs of electrons to the metal atom simultaneously. Example - ethylene diammine.