What is the predominant intermolecular force in the liquid state of each of these compounds: hydrogen fluoride (HF), carbon tetrabromide (CBr4), and methyl chloride (CH3Cl)

The predominant intermolecular force in Hydrogen Flouride (HF) is Hydrogen bonding

The predominant intermolecular force in carbon tetrabromide (CBr4) is London -Dispersion Forces

The predominant intermolecular force in methyl chloride (CH3Cl)  is a dipole-dipole force.

Explanation:

In hydrogen bonds, these are special dipole-dipole attractions between polar molecules in which a hydrogen atom is directly joined to a highly electronegative atom, e.g. oxygen, nitrogen or fluorine). Such molecules include water , hydrogen fluoride HF etc

In dispersion forces, these are weak attraction forces found between non-polar and polar molecules. The attractions here can be attributed to the fact that a non-polar molecule sometimes becomes polar because the constant motion of its electrons may lead to an uneven charge distribution at an instant. London forces are the weakest of all electrical forces that act between atoms and molecules.

Dipole-dipole Attractions are forces of attraction existing between polar molecules (unsymmetrical molecules), i.e. molecules having permanent dipoles, e.g. HCl, CH3Cl. Such molecules line up such that the positive pole of one molecule attracts the negative pole of another molecule.

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