Immiscible liquids may occasionally mix under violent conditions to form a mixture known as an emulsion.
Another property of liquids is their viscosity. The viscosity of a liquid describes the ease with which the layers of the liquid are able to slide past each other. A highly viscous liquid does not slide easily, whereas a non-viscous liquid slides easily. For example, syrup is more viscous than water.
The surfaces of liquids are subject to adhesive and cohesive forces. Adhesive forces describe the attraction between the liquid molecules and the molecules of the container. Cohesive forces describe the attraction of the molecules of liquid to other molecules of liquid. If the adhesive forces are stronger than the cohesive forces, the surface of the liquid forms a meniscus. In this case, the liquid molecules prefer to be bonded to the molecules of the container. Therefore, the level of the liquid along the sides of the container is higher than the level of the liquid in the center of the container and the surface has a concave appearance. If the cohesive forces are stronger, the level of the liquid will be higher in the center of the container than along the outside of the container.
