What is the strongest intermolecular force in carboxylic acids?

In carboxylic acids, hydrogen bonding is the strongest intermolecular force present. This is due to the -COOH functional group, where the hydrogen atom on the hydroxyl (-OH) part of the carboxylic acid can form strong hydrogen bonds with the oxygen atoms of other carboxylic acid molecules.

Hydrogen bonds are particularly strong among intermolecular forces because they occur between a hydrogen atom covalently bonded to a highly electronegative atom (like oxygen in the hydroxyl group) and another electronegative atom. In the case of carboxylic acids, this leads to significant attraction between molecules, which influences their physical properties, such as higher boiling and melting points compared to similar-sized molecules that engage in weaker types of intermolecular forces.

While ionic bonding and dipole-dipole interactions also occur in different contexts, they are not the primary forces in carboxylic acids as seen here. Instantaneous-induced forces, or London dispersion forces, are generally weaker and play a less significant role in the behavior of carboxylic acids, particularly when stronger hydrogen bonds are present. Thus, hydrogen bonding stands out as the most impactful intermolecular force in these compounds.