Directions: In the following questions, A statement of Assertion (A) i...
In MX6 & MX5 complexes there are four ligands in the same plane and all are identical ligands linked to the metal atom, so they don't show geometrical isomerism.
Thus, the assertion statement is correct.
Reason: In reason it is given that complexes with coordination number 6 will not show geometrical isomerism. Reason is wrong here as compounds with coordination number 6 have octahedral geometry and they can show geometrical isomerism.
So, the reason is false.
Hence, assertion is true but reason is false.
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Directions: In the following questions, A statement of Assertion (A) i...
Assertion (A): Complexes of MX6 and MX5L type do not show geometrical isomerism.
- Understanding Complexes: Complexes of the form MX6 (where M is a metal and X is a ligand) and MX5L (where L is a unidentate ligand) typically have a coordination number of 6 or 5.
- Geometrical Isomerism: Geometrical isomerism arises when ligands can be arranged in different spatial orientations around the central metal atom. Common in coordination number 4 (e.g., tetrahedral or square planar complexes) and 6 (octahedral), the presence of different ligand types (e.g., bidentate) can lead to isomerism. However, in MX6 complexes with six identical ligands, geometrical isomers cannot form.
Reason (R): Geometrical isomerism is not shown by complexes of coordination number 6.
- Coordination Number 6: While it is true that many complexes with a coordination number of 6 do not show geometrical isomerism, this is not universally applicable. For instance, octahedral complexes with different types of ligands (like in fac-mer isomerism) can show geometrical isomerism.
- Specificity of A: The assertion specifically addresses the MX6 and MX5L types, where MX6 has identical ligands and therefore cannot exhibit geometrical isomerism.
Conclusion
- Correct Evaluation: The assertion is true in the context of MX6 and MX5L complexes. However, the reason is misleading as it suggests that all coordination number 6 complexes lack geometrical isomerism, which is incorrect. Therefore, the correct choice is:
Option B: A is true but R is false.