Correct Answer: 6
Part X: [Pt(NH3)(H2O)BrCl]
Platinum(II) complexes are square planar. Since all four ligands are different, the complex shows two geometrical isomers (cis and trans).
X = 2
Part Y: [CrCl2(ox)2]3−
This is an octahedral complex with two bidentate oxalate (ox) ligands.
It shows:
• One cis form → optically active (Δ and Λ forms)
• One trans form → optically inactive
Number of optically inactive isomers = 1
Y = 1
Part Z: [Co(NH3)3(NO2)3]
This is an octahedral MA3B3 type complex.
Such complexes show two geometrical isomers:
• fac
• mer
Z = 2
Final Calculation
X + Y + Z = 2 + 1 + 2 = 6
Updated for JEE Main 2026: This PYQ is important for JEE Mains, JEE Advanced and other competitive exams. Practice more questions from this chapter.