What are hydrophilic molecules?

Hydrophilic molecules are those that have an affinity for water, primarily due to their ionic or polar covalent bonds. These characteristics allow them to form hydrogen bonds with water molecules, leading to their ability to dissolve in water. For instance, substances like sugars and salts are considered hydrophilic because they can interact readily with water, breaking apart and dispersing in solution.

On the molecular level, hydrophilic molecules often contain functional groups such as hydroxyl (-OH) or carbonyl (C=O), which contribute to their polarity. The polar nature of these molecules enables them to interact favorably with water, promoting solvation and dissolution.

In contrast, molecules that repel water or do not interact well with it are typically hydrophobic; these molecules are often non-polar and do not dissolve in water. Therefore, the defining characteristic of hydrophilic molecules is their ability to interact with water through polar or ionic bonds, making their solubility in water a distinguishing trait.