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

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

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

Topics of Discussion n Luminescence n Oxidation n Reaction Kinetics

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

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

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

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

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