Doppler Tim's Glow Tube

Materials
-Luminal
-Hydrogen peroxide
-Catalyst
-Funnel and tubing
***Teachers-Luminol demonstrations kits can be purchased through science distributors like Carolina.com


Procedure
The luminol solution an dcatalyst are poured into the left part of the funnel while the hydrogen peroxide solution is poured into the right part of the funnel. The solution will mix as both "sides" are released into the tube. A bright blue light is produced.


What's Going On?
Have you ever wondered how fireflies light up or what causes lightsticks to work? Both are caused by chemical reactions in which energy is released or given off as "cool" light. More specifically, these reactions involve chemiluminescence. A firefly lights up when an enzyme calle luciferase in its lower abdomen reacts with oxygen to produce energy emitted as light. Lightstickes are composed of two solutions, one of which is containde in a glass tube. By bending the lightstick, the glass tube is broken allowing the two solutions to mix. The result of this chemical reaction is the glow of the lightstick. In our experiment, luminol is oxidized by the hydrogen peroxide. The luminol is converted to an "excited state" product. Excess energy is shed by emitting a photon of light, allowing molecules to go from their excited state back to a ground state. The photon of light has a wavelength corresponding to the energy difference between the excited state and the ground state. It is a bit complicated but it sure is cool...