Question

The complex ion which shows geometrical isomerism is

• A. $\left[\mathrm{Cr}\right(H_{2}O{)}_4{\mathrm{Cl}}_2{]}^{+}$
• B. $\left[\mathrm{Pt}\right({\mathrm{NH}}_3{)}_3\mathrm{Cl}]$
• C. $\left[\mathrm{Co}\right({\mathrm{NH}}_3{)}_6{]}^{3+}$
• D. $\left[\mathrm{Co}\right(\mathrm{CN}{)}_5\left(\mathrm{NC}\right){]}^{3–}$

Answer 1

The correct option is A $\left[\mathrm{Cr}\right(H_{2}O{)}_4{\mathrm{Cl}}_2{]}^{+}$

As we know , $\left[Cr\right(H_{2}O{)}_{4}C{l}_2{]}^{+}$ is the only compound in the given options which is in the form of $M{A}_4{B}_2$. This form can be represented in terms of cis-isomer and tran-isomer.
Whereas for the rest of the options, they cannot show geometrical isomerism as they do not show variation in structures.