What is the interfacial tension (IFT) a measure of?

Interfacial tension (IFT) is a measure of the attractive forces at the interface between two immiscible fluids, such as oil and water. It characterizes how strongly the molecules of one fluid are attracted to the molecules of the other fluid. In the context of oil and water, a lower IFT indicates a stronger attraction between the molecules, which can influence processes such as oil recovery, emulsification, and even environmental spill responses. The ability of oil to either float or mix with water is directly linked to the interfacial tension. Higher interfacial tension suggests that there is less interaction and a more pronounced separation between the two fluids. Therefore, it accurately reflects the relationship between oil and water through the concept of attraction.