Question

Number of geometrical isomers of ${\left[ {Pt\left( {NH_3} \right)\left( {NO_2} \right)Py\left( {NH_2OH} \right)} \right]^+}$ is
A. 2
B. 3
C. 4
D. 5

Answer 1

Hint: In the given question we have to recognize the isomeric structures of the given complex of geometrical form. When a restricted rotation is present somewhere in a molecule it is said to be a geometrical isomerism and the compound is called a geometrical isomer.

Complete step by step solution:
Isomers are those molecules which have the same molecular formula whereas have a different array of the atoms in space. That contains any different arrangements which are simply due to the rotation of molecules as a whole, or rotation of particular bonds.
In the given complex ${\left[ {Pt\left( {NH_3} \right)\left( {NO_2} \right)Py\left( {NH_2OH} \right)} \right]^+}$ Pt is the central atom and is connected with four different ligand or we call groups therefore it will have 3 different structure according to their functional group attached to it. These are known to be their geometrical isomers of the complex.
Therefore, there are 3 geometrical isomers of the given complex.
 

Hence, option (B) is a correct answer.

Note: Geometric isomerism is also known as cis-trans isomerism or E-Z isomerism. The geometrical isomers occur where they have a restricted rotation somewhere in a molecule. To recognize the possibility of a geometric isomerism we obviously need to detect or have a restricted rotation somewhere in the complex of a molecule.