Which of the following are electrostatic interactions of permanent dipoles in polar molecules?

a. ion-dipole forces

b. hydrogen bonding

c. dipole-dipole forces

d. london dispersion forces

Answer;

C. Dipole-dipole forces

Explanation;Dipole-dipole forces are electrostatic interactions of permanent dipoles in molecules; includes hydrogen bonding. These interactions align the molecules to increase the attraction.Molecules that contain dipoles are called polar molecules and are very abundant in nature. For example, a water molecule (H2O) has a large permanent electric dipole moment.

The problem here is that according to aufbau principle before 3d orbital 4s subshell comes.after filling 3p orbital with electrons you have 4 electrons left, you place two in 4s with opposite spin and the other two in 3d in any of its two orbitals of total five orbitals with the same spin.