Which one of the following Coordination entities exhibits Facial and Meridional isomerism?

Step-by-step solution

Facial (fac) and Meridional (mer) isomerism is a type of geometric isomerism observed in octahedral complexes of the type [MA₃B₃] . In the complex [ Co ( H ₂ O )₃ ( NO ₂ )₃ ] , the central metal ion Co is coordinated to three water ligands and three nitrite ligands. This corresponds to the general formula [MA₃B₃] . When the three identical ligands occupy the corners of one triangular face of the octahedron, it is called the facial (fac) isomer. When the three identical ligands occupy positions around the meridian o