Which of the following is not a heteroleptic complex?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → [Co(NH3)6]3+
A complex in which the metal is bound to only one kind of ligand is homoleptic; one with more than one kind is heteroleptic.
Option (1) [Co(NH3)6]3+ — Not a heteroleptic complex (homoleptic). All six ligands are \( \ce{NH3} \).
Option (2) [Co(NH3)4Cl2]+ — A heteroleptic complex. Two kinds of ligand: NH3 and Cl−.
Option (3) [Co(H2O)3Cl3] — A heteroleptic complex. Two kinds of ligand: H2O and Cl−.
Option (4) [CoF3(H2O)3] — A heteroleptic complex. Two kinds of ligand: F− and H2O.
NCERT (2026-27 edition):
Homoleptic and Heteroleptic Complexes
