Question

Two isomers of a compound $\left[Co\right(N{H}_3{)}_{3}C{l}_3]$ $(M{A}_3{B}_3$ type) are shown in the figures. The isomers can be classified as:

• A. (i) fac-isomers (ii) mer-isomer
• B. (i) optical-isomer (ii) trans-isomer
• C. (i) mer-isomer (ii) fac-isomer
• D. (i) trans-isomer (ii) cis-isomer.

Answer 1

The correct option is A (i) fac-isomers (ii) mer-isomer

In fac-isomer, three $Cl$ atoms are present on one face of the octahedron. Similarly, 3 ammonia molecules are present on one face of the octahedron. All 3 same ligands have ${90}^o$ bond angle between them.

In mer-isomer, there is a ${90}^o;{90}^o;{180}^o$ bond angle between three same ligands.