Answer
a. dispersion force and dipole-dipole forces.
b. dispersion force and dipole-dipole forces.
c. dispersion force, hydrogen bonds, and dipole-dipole forces.
d. dispersion forces.
Work Step by Step
a. $O_{3}$ is polar molecule, polar bond exists in this molecule because of the difference in electronegativities of atoms in $O_{3}$. Thus dispersion force and dipole-dipole forces are present in $O_{3}$.
b. $HBr$ is polar molecule, polar bond exists in this molecule because of difference in electronegativities of atoms in $HBr$. Thus dispersion force and dipole-dipole forces are present in $HBr$.
c. In $CH_{3}OH$, all the bonds are nonpolar but some of all the bonds make the molecule polar. It also has hydrogen bonds. Hence dispersion forces, hydrogen bonds and dipole-dipole forces are present in the molecule.
d. $I_{2}$ is a non polar molecule. Hence only dispersion forces are present.
