CHEM 110 Lecture Notes - Dynamic Equilibrium, Intermolecular Force, Surfactant

• School: McGill University
• Department: Chemistry
• Course: CHEM 110
• Professor: Ariel Fenster

Document Summary

Surface tension: the energy, or work, required to increase the surface area of a liquid. As the temperature and the intensity of molecular motion increase, intermolecular forces become less effective less work is required to extend the surface of a liquid, meaning that surface tension decrease with increase temperate. Increase temperature results in a decrease of surface tension. A drop of water: the forces holding the drop together are cohesive forces while the forces between the liquid molecules and the surface are adhesive forces. Adding detergent to water: dissolves grease to expose clean surface, detergent lowers the surface tension of water lowers the energy required to spread drops into a film, known as a wetting agent. Stronger the intermolecular forces of attraction, the greater the viscosity. For liquids, viscosity decreases with increasing temperature, but for gases, the viscosity increase with increasing temperature.