Question

The average potential energy of two rotating polar molecules that are separated by a distance r has 1/r3 dependence.

Answer 1

False

Answer 2

The average potential energy between two rotating polar molecules (Keesom forces) is inversely proportional to the sixth power of the distance between them ($1/r^6$). This is due to the thermal averaging of dipole orientations. The statement claims a $1/r^3$ dependence, which is characteristic of stationary dipoles, not rotating ones.