Question

Match Column-I (Type of isomerism) with Column-II (Examples): \[ \begin{array}{ll} \textbf{Column-I} & \textbf{Column-II} \\ A.\ \text{Linkage isomerism} & 1.\ [Co(NH_3)_5SO_4]Br/[Co(NH_3)_5Br]SO_4 \\ B.\ \text{Ionisation isomerism} & 2.\ [Co(NH_3)_5(NO_2)]Cl_2/[Co(NH_3)_5(ONO)]Cl_2 \\ C.\ \text{Coordination isomerism} & 3.\ [Co(NH_3)_6][Cr(CN)_6]/[Cr(NH_3)_6][Co(CN)_6] \end{array} \]

• A. A-2, B-1, C-3
• B. A-1, B-2, C-3
• C. A-3, B-2, C-1
• D. A-2, B-3, C-1

Hint:

Remember these common examples: \[ \boxed{ \begin{aligned} NO_2^-,\;SCN^- &\rightarrow \text{Linkage isomerism}\\ \text{Counter ion exchange} &\rightarrow \text{Ionisation isomerism}\\ \text{Ligand exchange between complexes} &\rightarrow \text{Coordination isomerism} \end{aligned} } \] These examples are among the most frequently asked in Coordination Chemistry.

Answer 1

The Correct Option is A

Chain isomers share a molecular formula but differ in the branching of the carbon skeleton (e.g., n-butane vs isobutane); positional isomers differ in the location of a substituent or functional group on the same skeleton; functional isomers have different functional groups with the same formula (e.g., alcohol vs ether). Optical and geometric isomers are stereoisomers differing in spatial arrangement.