Chemiluminescence

1. Chemiluminescence Producing light with chemicals Rachel Eisenbraun Chemistry Outreach, Chem 292

2. Purpose • The purpose of this experiment is to demonstrate the process of chemiluminescence.

3. Demonstration • Equal amounts of an oxidizing solution and a luminescing solution were mixed. • The resulting blue solution glowed.

4. Topics of Discussion • Luminescence • Oxidation • Reaction Kinetics

5. Luminescence • Matter is luminescent if it gives off energy in the form of light. • Chemiluminescence is light which results from a chemical reaction • The light emitted in such reactions has differing degrees of intensity and lifetime.

6. Oxidation • Oxidation occurs when a molecule loses one or more electrons. • Whenever oxidation occurs, reduction must also occur. Reduction is the gain electrons. • The luminescing solution was oxidized in this experiment.

7. Reaction Kinetics • Kinetics simply refers to how fast a reaction will occur • Although this it was not shown in this demonstration, this experiment also demonstrates the effect of temperature on the rate of reactions. • If the solution were cooled, the reaction would occur slower causing the solution to glow longer but not as bright. • If the solution were heated up, the solution would glow brighter but not as long.

8. Conclusions • This demonstration produced light through a kind of chemical reaction called oxidation/reduction reaction. • The light was the result of chemical reactions • The light did not result in heat so is often termed “cold light”

9. Comments • The term "chemiluminescence" was first coined by Eilhardt Weidemann in 1888. • Chemiluminescence is a popular demonstration among teachers. • Glow sticks are a form of chemiluminescence. • Fireflies produce “cold light” by a chemiluminescent reaction