Are Glow Sticks Endothermic Or Exothermic?

Glow sticks emit light, but not heat. The glow stick reaction, which releases energy, is an exergonic reaction (energy-releasing). It is not an Exo heat-releasing (heat-releasing), reaction, however. Exothermic reactions can be considered a type of exergonic reaction. Exothermic reactions can be exergonic. However, not all exergonic reactions must be exergonic.

Heat-absorbing reactions. Although glow sticks aren’t heat-absorbing and therefore aren’t considered to be endothermic, they can be affected by the temperature. As the temperature drops, the rate of chemical reactions slows down and speeds up as the temperature rises. Refrigerating glow sticks will make them last longer. The rate at which the chemical reaction occurs will increase if you place a glowstick in hot water. Although the glow stick will be brighter, it will not work as fast.

The glow stick reaction is an example of chemical chemiluminescence. The light that is produced by a chemical reaction is called chemiluminescence. Because heat is not required to produce it, it’s sometimes called cool light.

How a Glowstick Works

Two separate liquids are contained in a light stick. One compartment contains a hydrogen peroxide solution and another compartment contains a phenyl oxide ester with fluorescent dye. The two solutions will react when you snap the glowstick. Although this reaction doesn’t emit light it does produce enough energy to excite electrons in fluorescent dye. Photons are created when excited electrons change from a higher to a lower energy status. The dye used determines the color of the glow sticks.