Final answer:
The sticking together of water molecules due to hydrogen bonding is called cohesion, resulting from the polar nature of water and strong intermolecular forces.
Step-by-step explanation:
The phenomenon by which hydrogen bonds cause water molecules to stick together is known as cohesion. Due to water's polarity, each water molecule is attracted to other water molecules because oppositely charged ends of the molecules attract each other. This attraction results in a weak interaction called a hydrogen bond, which occurs between the positive hydrogen end of one water molecule and the negative oxygen end of another. These bonds contribute to water being labeled as the 'universal solvent' due to its ability to dissolve a wide range of substances. Furthermore, hydrogen bonding leads to other unique properties of water such as high boiling points and the ability for water to expand upon freezing, which can be explained by the strong dipole-dipole interaction between the highly polar hydrogen and oxygen atoms within the molecule.