QJEEM23Chbf32: JEE Main 2023 Chemistry - Class 12 JEEM23Chbf32 Solution: Which halogen is known to cause the reaction given below :

The given reaction describes the formation of a copper(II) halide and the corresponding diatomic halogen molecule. Not all halogens will cause this reaction to occur.

This reaction is known to occur with iodine (I) because the formation of $\mathrm{I}_{2}$ (a diatomic iodine molecule) is easier due to the relatively low bond energy of the $\mathrm{I}-\mathrm{I}$ bond.

On the other hand, the bond energies of $\mathrm{Cl}-\mathrm{Cl}$ and $\mathrm{Br}-\mathrm{Br}$ are higher, making it more difficult for these diatomic halogen molecules to form. Thus, these halogens would not typically cause this reaction to occur.

Therefore, the correct answer is:

Option B : Only Iodine.