Question

What is the predominant intermolecular forces in the liquid state of each of the following compound : Hydrogen Fluoride $(HF)$, carbon tetrachloride $(CC{l_4})$ and dichloromethane $(C{H_2}C{l_2})$? either dipole-dipole forces , hydrogen bonding or dispersion forces

Answer 1

We know that the type of force acting within the molecule depends on the nature of the molecules participating in it, like whether they are the polar molecules or the non-polar molecules, or the electronegative or the electropositive atoms.

Complete answer:
Since we know that the nature of the particles defines the forces acting on them, let's discuss it.
Since, we know that the hydrogen bonding operates between the electropositive and the most electronegative atom, and as we can see from the options given to us that the hydrogen fluoride molecule will, have hydrogen bonding between them as the fluorine molecule is the highly electronegative atom.
Whereas on the other hand, the dipole-dipole forces will operate between the dichloromethane $(C{H_2}C{l_2})$ molecule.
And when we look for the carbon tetrachloride $(CC{l_4})$, this molecule will have the dispersion force or the London forces.
Hence from the above discussion, the answer is crystal clear.

Note:
In the carbon tetrachloride $(CC{l_4})$ molecule, the dispersion forces operate as, this is the non-polar molecule and we know that between the non-polar molecule, the only force or the primary acting force is the London forces or the dispersion forces. also note that the dispersion force is also present in the Hydrogen Fluoride $(HF)$ molecule but it is not the primary force.