The intermolecular interaction that is dependent on the inverse cube of distance between the molecule is :

Options

A. ion-ion interaction
B. ion-dipole interaction
C. London force
D. hydrogen bond

Answer

B

Explanation

Ion-ion interaction is dependent on the square of distance, i.e. ion-ion interaction `prop (1)/(r^(2))`
Similarly, ion-dipole interaction `prop (1)/(r^(3))`
London force `prop (1)/(r^(6))` and dipole-dipole interaction `prop (1)/(r^(3))` Superficially it seems as both ion-dipole interaction and hydrogen bonding vary with the inverse cube of distance between the molecules but when we look at the exact expressions of field (force) created in two situations, it comes as
`|E| or |F| =(2|P|)/(4pi in r^(3))" "` (In case of ion-dipole interaction)
and `F=(2q^(2)r-4q^(2)q)/(4pi in_(0) r^(3))" "` (In case of dipole-dipole interaction)
from the above, it is clear that the ion-dipole interaction is the better answer as compared to dipole-dipole interaction, i.e. hydrogen bonding.