JEE Advanced 2013 · Paper 1 · Chemistry Q31

ChemistryMultiple correct+4 / -1Question 31 of 60

The pair(s) of coordination complexes/ions exhibiting the same kind of isomerism is(are)

\ce{[Cr(NH3)5Cl]Cl2}

and

\ce{[Cr(NH3)4Cl2]Cl}

\ce{[Co(NH3)4Cl2]+}

and

\ce{[Pt(NH3)2(H2O)Cl]+}

\ce{[CoBr2Cl2]^{2-}}

and

\ce{[PtBr2Cl2]^{2-}}

\ce{[Pt(NH3)3(NO3)]Cl}

and

\ce{[Pt(NH3)3Cl]Br}

Answer and worked solution

Official answer: B, D

(A) $\ce{[Cr(NH3)5Cl]Cl2}$ shows no geometrical isomerism (MA₅B), while $\ce{[Cr(NH3)4Cl2]Cl}$ shows cis/trans. Different.
(B) Octahedral $\ce{[Co(NH3)4Cl2]+}$ (MA₄B₂) and square-planar $\ce{[Pt(NH3)2(H2O)Cl]+}$ (MA₂BC) both show cis/trans isomerism. Same. ✓
(C) Tetrahedral $\ce{[CoBr2Cl2]^{2-}}$ shows none; square-planar $\ce{[PtBr2Cl2]^{2-}}$ shows cis/trans. Different.
(D) Both can exchange the ligand inside with the counter-ion (NO₃⁻/Cl⁻ and Cl⁻/Br⁻): ionisation isomerism. Same. ✓

(B), (D)

Topics:Isomerism in complexes

JEE Advanced 2013 · Paper 1, Chemistry question 31