The principal source of the difference in the normal boiling points of ICI (97°C; molecular mass 162 amu) and Br2(59°C; molecular mass 160 amu) is:a. ICI has greater strength of hydrogen bonding than Br2 b. ICI has stronger dipole-dipole interactions than Br2c. ICI has stronger dispersion forces than Br2 d. The I-CI bond in ICl is stronger than the Br-Br bond in Br2 e. ICI has a greater molecular mass than Br2

The difference in the boiling points of ICl and Br2 is mainly due to the dipole-dipole interactions present between iodine and chlorine in the ICl molecule because as there is difference in electronegativity between iodine and chlorine these type of forces arise

As the dipole-dipole interactions are stronger, the stronger will be the boiling point of that compound because the forces between the molecules increases and as a result the boiling point of the compound increases

In case of Br2 as both are bromine atoms there will be no difference in electronegativity and therefore these type of interactions are not present

Molecular mass can also be a explanation for difference in normal boiling points because more molecular mass means more will be the vander waals forces but as dipole interactions are stronger than vander waals forces the major factor will be due to dipole interactions