Question

What is the predominant intermolecular force in the liquid state of each of these compounds: hydrogen fluoride (HF), carbon tetrabromide (CBr4), and nitrogen trifluoride (NF3)? Force(s): Dipole-dipole Hydrogen Bonding Dispersion

Answer 1

Answer:

HF - hydrogen bonding

CBr4 - Dispersion

NF3 - Dipole-dipole

Explanation:

Hydrogen bonding occurs when hydrogen is covalently bonded to a highly electronegative atom such as fluorine, chlorine nitrogen, oxygen etc. Hence the dominant intermolecular force in HF is hydrogen bonding.

CBr4 is nonpolar because the molecule is tetrahedral and the individual C-Br dipole moments cancel out leaving the molecule with a zero dipole moment hence the dominant intermolecular force are the dispersion forces.

NF3 has a resultant dipole moment hence the molecules are held together by dipole-dipole interaction.