The Aloha Chemical Sunset - Chemical Demonstration Kit
By: David Katz, Pima Community College, Tucson, AZ
Item #: AP8988
The Aloha Chemical Sunset Chemical Demonstration Kit shows how light passing through a colloidal suspension is affected by the size of the colloidal particles. Two solutions are mixed, producing a spectacular multicolored "sunset."
Do you and your students need a spring break already? If you can't see a Hawaiian sunset in person, simulate it in the classroom! This fun demonstration shows how light passing through a colloidal suspension is affected by the size of the colloidal particles—this is known as the Tyndall effect. Two solutions are mixed in a Petri dish on an overhead projector, producing a spectacular multicolored "sunset."Enough materials are included to perform the demonstration seven times.
Concepts: Colloids and precipitates, Tyndall effect/light scattering.
Time Required: 10-15 minutes
Materials Provided: Sodium thiosulfate solution, hydrochloric acid solution, Petri dish, and chemical sunset cutouts.