Question

Which of the following complexes exhibit geometrical isomerism?
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• A. I, II & III only
• B. II, III & IV only
• C. I, II & IV only
• D. II & III only

Hint:

Geometrical isomerism is common in square planar and octahedral complexes, especially when ligands differ in position.

Answer 1

The Correct Option is C

Step 1: Identify geometrical isomerism
Geometrical isomerism occurs in complexes where ligands can be arranged differently in space around the central atom. Step 2: Analyze each option
\begin{itemize} \item I. \ce{[Co(en)(NH3)2Cl2]Cl}: Octahedral with two different ligands — exhibits geometrical isomerism (cis/trans). \item II. \ce{[Co(NH3)4Cl2]Cl}: Octahedral, square planar-like — exhibits geometrical isomerism. \item III. \ce{[Co(en)3]Cl3}: Tris-chelate complex with symmetrical bidentate ligands — does not show geometrical isomerism. \item IV. \ce{[Co(en)2Cl2]Br}: Octahedral with two Cl ligands — exhibits geometrical isomerism. \end{itemize}