Question

question 7 (1 point)
place the following compounds in order of decreasing strength of intermolecular forces, starting with the strongest forces.
hf h₂ nbr₃
hf > h₂ >nbr₃
h₂ > hf >nbr₃
h₂ >nbr₃ > hf
nbr₃ > h₂ > hf
hf > nbr₃ > h₂

Explanation:

• HF: It has hydrogen bonding (a strong type of dipole - dipole interaction). Hydrogen bonding occurs when hydrogen is bonded to a highly electronegative atom (in this case, fluorine).
• NBr₃: It is a polar molecule. Polar molecules have dipole - dipole forces. The electronegativity difference between nitrogen and bromine makes the molecule polar.
• H₂: It is a non - polar molecule. Non - polar molecules have only London dispersion forces, which are the weakest of the intermolecular forces.

Since hydrogen bonding (in HF) is stronger than dipole - dipole forces (in NBr₃), and dipole - dipole forces are stronger than London dispersion forces (in H₂).

Answer:

HF > NBr₃ > H₂ (the last option)