What are substances that lower surface tension called?

Surfactants are substances that lower the surface tension of a liquid. They achieve this by accumulating at the air-water interface and disrupting the cohesive forces between water molecules. This results in a decreased surface tension, allowing the liquid to spread more easily, which is particularly important in various biological and industrial processes.

Surfactants play crucial roles in areas such as detergents, where their ability to reduce surface tension allows for better interaction with oils and dirt, aiding in cleaning applications. They are also vital in biological systems; for example, pulmonary surfactants in the lungs help reduce the surface tension of the alveoli, preventing their collapse and enabling efficient gas exchange.

Understanding the function and importance of surfactants helps clarify their role in both natural environments and engineered products, showing how they facilitate various chemical interactions by modifying surface characteristics.