Molecules that are attracted to water are referred to as what?

Molecules that are attracted to water are referred to as hydrophilic. This term comes from the Greek words "hydro," meaning water, and "philos," meaning loving. Hydrophilic substances have a tendency to interact with water molecules, which is often due to their polar or charged nature. Because of this polarity, they can form hydrogen bonds with water, allowing them to dissolve in it or form stable suspensions. Common examples of hydrophilic molecules include sugars, salts, and many proteins.

In contrast, hydrophobic molecules do not interact favorably with water. These molecules are typically non-polar and tend to aggregate together in aqueous environments, which is a key principle in biological systems, particularly in the formation of cellular membranes. Hydrogen-bonding molecules refer more generally to any molecules capable of forming hydrogen bonds, which could include both hydrophilic and certain other types of molecules. Therefore, recognizing hydrophilic as the appropriate classification for water-attracting molecules is essential in understanding interactions in biological systems.