Which molecule/s contain/snet dipoles?

• A. e
• B. f
• C. both of e and f
• D. none of them

Answer: (A)

Verified step by step guidance

1. Identify the molecular geometry of each molecule. For PBr₃, the central phosphorus atom is bonded to three bromine atoms and has one lone pair, resulting in a trigonal pyramidal shape. For CO₂, the carbon atom is double-bonded to two oxygen atoms, resulting in a linear shape.
2. Determine the electronegativity differences between the atoms in each molecule. Bromine is more electronegative than phosphorus, and oxygen is more electronegative than carbon.
3. Analyze the dipole moments in each molecule. In PBr₃, the dipole moments do not cancel out due to the asymmetrical trigonal pyramidal shape, resulting in a net dipole moment. In CO₂, the dipole moments of the C=O bonds are equal and opposite, canceling each other out due to the linear shape, resulting in no net dipole moment.
4. Conclude that PBr₃ has a net dipole moment because of its molecular geometry and the presence of polar bonds, while CO₂ does not have a net dipole moment due to its linear geometry and the cancellation of dipole moments.
5. Based on the analysis, determine that the molecule with a net dipole is PBr₃, corresponding to option e.