Which of the following is a heteroleptic complex?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → \([Co(NH_3)_4Cl_2]\)
In \( \ce{[Co(NH3)4Cl2]} \) cobalt carries two kinds of ligands, four \( \ce{NH3} \) molecules and two \( \ce{Cl-} \) ions, so it is heteroleptic.
Why the other options are incorrect
Option (1) \([Cr(NH_3)_6]^{3+}\) — Incorrect. All six ligands are \( \ce{NH3} \): homoleptic.
Option (2) \([Fe(NH_3)_6]^{3+}\) — Incorrect. All six ligands are \( \ce{NH3} \): homoleptic.
Option (4) \([Mn(CN)_6]^{4-}\) — Incorrect. All six ligands are \( \ce{CN-} \) ions: homoleptic.
NCERT (2026-27 edition):
Homoleptic and Heteroleptic Complexes
