Light is generated by a chemical reaction called “chemiluminescence". Typical glow sticks as chemical reactants use: a hydrogen peroxide solution ( which is called the "activator" ) a solution of phenyl oxalate ester and a fluorescent dye (which makes the colour). The activator is stored in a thin glass capsule (comp. B on the diagram above). When the glass capsule is broken (by flexing a glow stick) the activator is released, and mixing the components (shaking the glow stick) initiates the reaction. Depending on components used, the chemical reaction can last (glow sticks can glow) from a few minutes to many hours. Heating the glow sticks (providing extra energy) will speed up the reaction, what will result in brighter light but will shorten the glow time. The reaction will slow down in low temperatures (the light will dim, but the glow time will be longer).
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