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Day in the Dark Demonstrations with Jamie Benigna

firewatch

Publication 91825

Price: FREE

Use this lively presentation with a multitude of related and exciting demonstrations to explore the basic principles of light absorption and emission. An unforgettable lesson plan for fluorescence, phosphorescence, and chemiluminescence! Demonstration 1. Excited States Help students learn the Bohr Theory and the basic concepts of energy levels, ground states, and excited states by performing this energetic demonstration. Demonstration 2. Permanent Excitation When ordinary table salt is irradiated, it turns brown due to “color centers” (defects) in the excited-state crystal structure. When the irradiated salt is heated on a hot plate, it gives off flashes of light and turns white as the excited-state crystal returns to the ground state. The thermal fluorescence of irradiated table salt is used to illustrate crystal defects. Demonstration 3. Fluorescence Wow your students with all the everyday items that glow under ultraviolet light.