Hydrogen bonding is present in

Which of the following molecules can form hydrogen bonding with itself?

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: Dipole-dipole interactions are the only non-covalent interactions resulting in hydrogen bond formation.
Reason $R$: Fluorine is the most electronegative element and hydrogen bonds in $HF$ are symmetrical.

The correct order of boiling points of hydrogen halides is

Which of the following concepts best explains why $o$-nitrophenol is more volatile than $p$-nitrophenol?

The correct order of boiling point in the following compounds is