Surface tension refers to a liquid’s natural resistance to external forces by creating a thin film. It happens because liquid molecules stick together, forming cohesive forces. Liquids with stronger intermolecular forces exhibit higher surface tension, like water due to its robust hydrogen bonds.

Surface tension is measured in newtons per meter (N/m) or joules per meter square (J/m²). In a rectangular container with fixed sides of length L, surface tension (Tflat) can be calculated using the formula Tflat = 0.5F/L, where F represents the force on the surface.

It’s an inherent property of liquids, influenced by temperature, composition, and molecular activity. With rising temperature, cohesive forces weaken due to increased thermal activity, causing a decrease in surface tension.