Teaching surface tension using easy-to-do experiments in undergraduate classes

Abstract

Teaching the concepts of surface tension can be surprisingly improved by easy-to-do experiments. Therefore, an experimental guide was implemented in an undergraduate class, using reusable kits with inexpensive materials of easy access. This approach does not require any laboratory infrastructure and can be performed in any classroom. The experiments initially involve floating clip on water. Then, droplet size and amount of liquid per drop of water, alcohol and a mixture of these liquids was related to the surface tension and also the intermolecular interactions.