Question

The six structures (I-VI) of molecules where $X,Y,Z$ are atoms of different elements with different electronegativities, are shown below. The molecules are regular tetrahedral species. Assume the bond lengths in all the structures to be the same.
Identify the pair(s) of structures of molecules in which both the members have the same magnitude of dipole moment.

• A. I and III
• B. II and V
• C. IV and VI
• D. I and V

Answer 1

Answer: (B)

II and V

The option (B) is the correct answer.
In structures II and V both the members have the same magnitude of dipole moment. Both structures have two $Z-X$ bonds and two $Z-Y$ bonds. In other words, they have identical structures.