Question

Regarding dipole-dipole attractions the incorrect statement is:

• A. dipole-dipole attractions are more, if the molecules have height dipole moment values.
• B. in liquid $HBr$ dipole-dipole attractions are present
• C. dipole-dipole interaction energy between stationary polar molecules as in solids $\propto r^{-3}$
• D. dipole-dipole interaction energy between rotating molecules $\propto r^6$

Answer 1

Answer: (A), (D)

dipole-dipole attractions are more, if the molecules have height dipole moment values.
dipole-dipole interaction energy between rotating molecules $\propto r^6$

The correct option are $A$ and $D$. The correction of statement $A$ is Dipole-dipole attraction are more if the charge of separation in a molecule is large. Larger the difference in electronegativities of bonded atoms, the larger will be the dipole moment.

The correction of statement $D$ is dipole-dipole interaction energy between rotating molecules is $\propto \frac{1}{r^6}$.