01:160:161 Chapter Notes - Chapter 11.4-11.6: Intermolecular Force, Capillary Action, Surface Tension
20 Dec 2018
School
Department
Course
Professor
Document Summary
The most important manifestation of intermolecular forces is the existences of molecular liquids and solids. A molecule at the surface has relatively fewer neighbors with which to interact and it is therefore inherently less stable- it has higher potential energy- than those in the interior. (remember that attractive interactions with other molecules lower potential energy) The surface tension of a liquid is the energy required to increase the surface area by a unit amount. Surface tension decreases as intermolecular forces decrease. A sphere is the geometrical shape with the smallest surface area to volume ratio: the formation of a sphere minimizes the number of molecules at the surface, thus minimizing the potential energy of the system. Another manifestation of intermolecular forces is viscosity, the resistance of a liquid to flow. Viscosity is measured in a unit called the poise (p), defined as 1 g/cm x s.
