MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

A homoleptic complex has only one type of ligand attached to the central metal atom or ion. A heteroleptic complex has more than one type of ligand attached to the central metal atom or ion. Pentacarbonyliron(0) is [Fe(CO)_5], which has only CO ligands (homoleptic). Triamminetrinitrocobalt(III) is [Co(NH_3)_3(NO_2)_3], which has two different types of ligands, NH_3 and NO_2^ - (heteroleptic). Tetraamminecopper(II) ion is [Cu(NH_3)_4]^ 2+ , which has only NH_3 ligands (homoleptic). Tetracyanonickelate(II) ion is [Ni(CN)_4]^ 2- , which has only CN^ - ligands (homoleptic). Thus, Triamminetrinitrocobalt(III) is the heteroleptic complex.