Both geometrical and optical isomerism are exhibited by

Options

A. Dichlorobis (ethylenediamine) cobalt (III) ion
B. Pentaamminechlorocobalt (III)
C. Triamminotrichlorocobalt (III) ion
D. Tetraamminedichlorocobalt (III) ion

Answer

A

Explanation

Complex of the type `[M( A A)_2X_2] or [M ( A A)_2 XY]` exhibit optical activity . `[CoCl_2 (e n)_2]^+ ` forms geometrical isomers (cis and trans form). It is interesting to note that trans form does not show optical isomerism, i.e. it cannot be resolved into optical isomers. The reason is that the molecule has plane of symmetry. On the other hand, the cis– isomer is unsymmetrical and can be resolved into optical isomers