Final answer:
Without the full molecular structures for molecules (a) and (b), it is not possible to determine which has a higher dipole moment.
The dipole moment depends on molecular geometry, bond angles, bond lengths, and electronegativity differences.
Step-by-step explanation:
The dipole moment of a molecule is the vector sum of the dipole moments of its individual bonds. When determining which molecule has a higher dipole moment between two given molecules, one must consider the molecular geometry and the direction in which the bond dipoles point.
In the given examples without specific molecular structures, it is not possible to definitively determine which molecule has a higher dipole moment as full molecular structures are not provided.
However, discussing the principles, if molecule (a) has a molecular dipole moment pointing immediately between atoms A and C, and molecule (b) has a molecular dipole moment pointing along the A-B bond toward A, the molecule with the larger net dipole moment would depend on the bond angles, bond lengths, and differences in electronegativity among atoms A, B, and C.
Dipole moments are influenced by the molecule's symmetry and the electronegativities of the atoms involved. For example,
CO₂ is a linear molecule with two polar C-O bonds that are equal in magnitude and oriented at 180° to each other, resulting in no net dipole moment. Conversely, H₂O has a bent shape, causing the bond dipoles not to cancel and resulting in a net dipole moment.