Which molecule has dipole-dipole intermolecular forces?

Question

1. BCl₃
2. P₄
3. CCl₄
4. BH₃
5. PCl₃

Answer 1

PCl3. The Lewis structure and VSEPR theory predicts a tetrahedral electron pair geometry and a trigonal pyramidal molecular structure. The P-Cl bond is polar, and the trigonal pyramidal structure has an overall dipole moment which leads to dipole-dipole intermolecular forces.