Question

The relatively high boiling point of HF can be correctly explained by which of the following?

(A) HF gas is more ideal.
(B) HF is the strongest acid.
(C) HF molecules have a smaller dipole moment.
(D) HF is much less soluble in water.
(E) HF molecules tend to form hydrogen bonds."

Answer 1

The high boiling point of HF is due to the strong hydrogen bonds formed between its molecules, a result of the large electronegativity difference between hydrogen and fluorine.

Step-by-step explanation:

The relatively high boiling point of hydrogen fluoride (HF) as compared to other hydrogen halides is primarily due to the hydrogen bonds it forms. The large difference in electronegativity between the hydrogen and fluorine atoms in HF results in a significant partial positive charge on hydrogen and a correspondingly large partial negative charge on the fluorine atom. This disparity allows HF molecules to engage in very strong dipole-dipole interactions known as hydrogen bonding, which are much stronger than the van der Waals forces present in other hydrogen halides. Accordingly, the correct explanation for the high boiling point of HF is that HF molecules tend to form hydrogen bonds (Option E).