Question

Three arrangements are shown for the complex $\left[Co\right(en\left)\right(N{H}_3{)}_{2}C{l}_2{]}^{+}.$ Pick up the wrong statement(s)

• A. I and II are geometrical isomers
• B. II and III are optical isomers
• C. I and III are optical isomers
• D. II and III are geometrical isomers

Answer 1

Answer: (B), (C), (D)

The correct options are
B II and III are optical isomers
C I and III are optical isomers
D II and III are geometrical isomers

I and II are geometrical isomers.
In (I) two chlorine atoms are cis to each other. It is cis isomer.
In (II) two chlorine atoms are trans to each other. It is trans isomer.
Hence they are geometrical isomers of each other.
For optical isomers plane of symmertry should not be there while in (II) and (III) there is plane of symmetry.
Hence option B, C are incorrect.
Also the (II) and (III) are not geometrical isomers as both have trans Cl atom and cis $N{H}_3$ atoms.