Final answer:
The intermolecular force between the O in one NaOH molecule and the H in another is hydrogen bonding, which is a strong type of dipole-dipole interaction.
Step-by-step explanation:
The intermolecular force between the oxygen (O) in one sodium hydroxide (NaOH) molecule and the hydrogen (H) in another NaOH molecule is most specifically described as hydrogen bonding. This type of force occurs between molecules that have hydrogen atoms bonded to highly electronegative atoms, such as oxygen, nitrogen, or fluorine. In the case of NaOH, the hydrogen bond can form between the partially positive hydrogen atom on one NaOH molecule (the hydrogen bond donor) and the lone pair of electrons on the partially negative oxygen atom of another NaOH molecule (the hydrogen bond acceptor).
Hydrogen bonds are considered strong dipole-dipole interactions due to the significant differences in electronegativity between hydrogen and highly electronegative atoms. These bonds contribute to various physical properties, such as higher boiling points, as seen in water due to strong O…H hydrogen bonding between water molecules. While hydrogen bonds are weaker than covalent bonds (intramolecular forces), they are stronger than other van der Waals forces like London dispersion forces and general dipole-dipole interactions.