AIIMS 2019 Chemistry Nomenclature of Coordination Compounds MCQ Question

The IUPAC name of [Co(NO₂)(NH₃)₅]Cl₂ is Pentaammine nitrito-O⁻cobalt(III) chloride because the nitrite ion (NO₂⁻) is coordinated to the cobalt ion through the oxygen atom, which is indicated by the "O⁻" in the name. In contrast, option A incorrectly suggests that the nitrite is coordinated through nitrogen (N⁻), while options C and D incorrectly assign the oxidation state of cobalt as (II) instead of (III). Understanding the coordination of ligands and their binding sites is crucial for accurate nomenclature in coordination chemistry.