Question

The total number of possible isomers for the complex compound [CuII(NH3)4][PtIICl4] are
A . 3
B . 4
C . 5
D . 6

Answer 1

Hint: In this question we have to use the concept of isomers of a coordination compound and find out the number of isomers in [CuII(NH3)4][PtIICl4].
Isomers are two or more distinct substances with the same chemical formula but different physical and chemical characteristics. Despite having the same formula, they come in many colors.

Complete answer:When it comes to coordination compounds, there are primarily two types of isomerism:
In coordination compounds, there is stereoisomerism and structural isomerism.
Stereoisomers are isomers that have identical atoms and set of bonds but differ only in how these bonds are oriented relative to one another. These are further separated into:
Geometric isomerism: Tetrahedral complexes cannot be geometrically isomers, although square, planar, and octahedral complexes can.
Optical isomerism: While not conceivable for square and planar complexes, this isomerism is possible for tetrahedral and octahedral complexes.

Structural isomers are isomers with the same molecular formula but different atomic arrangements and bonding patterns.
For [CuII(NH3)4][PtIICl4] the total number of possible isomers is 4.
[Cu(NH3)4​][PtCl4​]
[Cu(NH3​)3​Cl][PtCl3​NH3​]
[Cu(NH3)Cl3​][PtCl(NH3​)3​]
[Cu(Cl)4​][Pt(NH3​)4​]

The correct answer is B.

Additional Information:
Subdivisions of structural isomerism include:
Coordination isomerism: In this case, the compounds have interchanged certain ligands from the cationic to the anionic sections, resulting in complex anionic and cationic components.
Ionization isomerism: In this case, isomers arise when several ions combine in a solution.
Hydrate Isomerism - This isomerism is a type of ionization isomerism in which the compounds differ by the number of solvent molecules directly bonded to the metal ion.

Note: Cis - [Cu(NH3)2Cl2​][PtCl2(NH3​)2​] and trans - [Cu(NH3)2Cl2​][PtCl2(NH3​)2​] might be added as an isomer but these two structures do not exist due to the unsatisfied charge on complex. The charge on both coordination spheres is zero.