demonstrations

Fluorescence Rocks! Exploring Glowing Sodalite

Syenite rocks containing sodalite that fluoresce yellow have been found on Lake Superior beaches in recent years and are of interest to collectors. The fluorescence of this mineral, which can be found in other localities, can be shown in classrooms and studied spectroscopically. Its structure can also be modeled with LEGO bricks, enabling further classroom connections.

Demonstrating the Glass Transition of Polylactic Acid with a Rattle

Polylactic acid (PLA) exhibits a glass transition from hard and brittle to soft and rubbery when immersed in boiling water. PLA-based structures containing a small metal object can be used as rattles when they are shaken. The sound of the rattles change when they are heated above or cooled below their glass transition, enabling them to be used as demonstrations.

Demo A Day IV

Dean Campbell uses demonstrations and props to illustrate concepts while teaching his collegiate Materials Chemistry course. Many of the examples described are also suitable for use in high school and collegiate General Chemistry courses.