Question

$[Cr{{(N{{H}_{3}})}_{6}}]$ $[Cr{{(SCN)}_{6}}]$ and $[Cr{{(N{{H}_{3}})}_{2}}{{(SCN)}_{4}}]$ $[Cr{{(N{{H}_{3}})}_{4}}{{(SCN)}_{2}}]$ are examples of what type of isomerism?
A) Ionisation isomerism
B) Linkage isomerism
C) Coordination isomerism
D) Solvate isomerism

Answer 1

Hint: The answer to this question is based on the concept of isomerism that has the definition in the coordination chemistry part and this gives you the correct answer. Isomers are the molecules that have the same molecular formula and differ by arrangement of elements in them.

Complete answer:
We have studied about the different types of isomerism in our lower classes of chemistry which is included in the inorganic chemistry chapters. Here, let us see the basic concept about isomerism and their types which helps us to figure out the correct answer.
- Isomerism is nothing but the phenomenon in which more than one compound is having the same chemical formula but different chemical structures.
- The two main types of isomerism are structural isomers and constitutional isomerism.
- Apart from these two main types of isomerism, there are also several others which also includes coordination isomerism, linkage isomerism, ionisation isomerism etc., of which the names given are based on the type of arrangement of atoms in a molecule.
Now, if we see the given molecule, the two original molecules that is$[Cr{{(N{{H}_{3}})}_{6}}]$ and $[Cr{{(SCN)}_{6}}]$ has all the atoms attached are same but the isomerised form has an exchanged ligands which basically is by the coordination of these two complexes that is $[Cr{{(N{{H}_{3}})}_{2}}{{(SCN)}_{4}}]$ and $[Cr{{(N{{H}_{3}})}_{4}}{{(SCN)}_{2}}]$

Therefore, based on these above facts we can say that the correct answer is option C) Coordination isomerism.

Note: Note that coordination isomerism is the isomerism in which the composition of the coordination complex varies but there are no changes in the oxidation state of the central metal atom.