What occurs when a hydrophobic substance is placed in water?

When a hydrophobic substance is placed in water, it tends to form droplets rather than dissolving completely. This behavior is due to the molecular structure of hydrophobic substances, which are nonpolar and do not interact favorably with water's polar molecules. Water molecules form hydrogen bonds with each other and tend to exclude nonpolar substances. As a result, instead of dispersing in water, hydrophobic substances aggregate to minimize their exposure to water. This creates distinct droplets, which allows them to maintain a lower energy state by reducing contact with the surrounding water molecules.

The other options do not accurately describe the behavior of hydrophobic substances in water. They either suggest processes that do not occur (like reacting chemically or increasing solubility) or misrepresent the interaction with water (like dissolving completely).