Question

The isomerism exhibited by the octahedral complex $[\mathrm{Co(NH_3)_4Br_2}]Cl$ is:

• A. Geometrical
• B. Optical
• C. Linkage
• D. Coordination
• E. Ionisation

Hint:

In octahedral complexes, cis-trans isomerism is common when two identical ligands are adjacent or opposite to each other.

Answer 1

The Correct Option is A

Step 1: Analyze the geometry of the complex.
The given complex is: \[ [\mathrm{Co(NH_3)_4Br_2}]Cl \] This complex is octahedral, as cobalt has six coordination sites (four from \( \mathrm{NH_3} \) and two from \( \mathrm{Br^-} \)).

Step 2: Identify the type of isomerism.
For an octahedral complex like \( [\mathrm{Co(NH_3)_4Br_2}] \), if the two \( \mathrm{Br^-} \) ligands occupy different positions (such as adjacent or opposite), the complex will show geometrical isomerism.

Step 3: Final conclusion.
Since the ligands \( \mathrm{Br^-} \) can occupy different spatial arrangements, the complex shows geometrical isomerism.
Thus, the correct answer is: \[ \boxed{(1)\ \text{Geometrical}} \]