# What is the force of intermolecular attraction that operates in ethanol?

The dominant intermolecular force that operates in ethanol is $\text{hydrogen bonding.}$
The normal boiling point of ethane, ${H}_{3} C - C {H}_{3}$, is $- 89$ ""^@. The normal boiling point of ethanol, ${H}_{3} C - C {H}_{3}$, is $78.1$ ""^@. As in water, hydrogen bonding occurs between the protic hydrogen and the electronegative oxygen atoms on adjacent ethanol molecules, i.e. ${H}_{3} C - C {H}_{2} {O}^{\delta -} - {H}^{\delta +}$, and this constitutes a potent intermolecular force.