JCE Software Chemistry Comes Alive!
Light Sticks

Light sticks are demonstrated.

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Narrative
Commercially available light sticks contain a solution in a glass vial. When the vial is broken, a second solution mixes with the first and light is generated. Different dyes give off different colors when they are caused to fluoresce by the light of the chemiluminescent reaction. Light sticks give off light from 3 to 8 hours, depending on the concentrations of reactants.

Discussion
Typical lightstick components are a phenyl oxalate ester with a fluorescent dye and, in the glass vial, a dilute solution of hydrogen peroxide (H2O2) and a catalyst in a solvent. When the vial is broken, the ester and the hydrogen peroxide react in the presence of the catalyst, forming an intermediate. This process causes a transfer of energy, exciting electrons in the dye molecules to a higher level. As electrons return to the ground state, light is emitted.