What’s the difference between cohesion and adhesion? These two terms are often used in the context of liquids, particularly water, and play a crucial role in various natural phenomena and everyday applications. While they are related concepts, they refer to distinct properties of liquids.
Cohesion is the attraction between molecules of the same substance. It is responsible for the tendency of liquid molecules to stick together. This property is evident in water droplets, which maintain their shape due to the cohesive forces between their molecules. Cohesion is what allows water to climb up the stems of plants, a process known as capillary action. It also contributes to the formation of surface tension, which is the resistance of a liquid surface to penetration by another substance.
Adhesion, on the other hand, refers to the attraction between molecules of different substances. This property is responsible for the ability of liquids to adhere to surfaces. For example, water can stick to glass or other materials, allowing it to form droplets on those surfaces. Adhesion is essential for the process of wetting, where a liquid spreads out on a solid surface. It is also involved in the formation of emulsions, such as oil and water mixtures, where the liquids are stabilized by the adhesion between their molecules.
In summary, cohesion is the attraction between molecules of the same substance, while adhesion is the attraction between molecules of different substances. Both properties are vital in understanding the behavior of liquids and their interactions with other materials.
