LIGHTING:GLOW STICKS

GLOW STICKS

Light is a form of energy that can be emitted through a variety of processes. All of these processes rely on the same basic principle: energy excites an atom’s electrons, and when these electrons return to their ground state they emit particles of light called photons. A light stick uses a chemical reaction instead of electricity to excite the atoms in a material. The chemical reaction typically involves several different steps. A typical commercial light stick holds a solution of hydrogen peroxide, phenyl oxylate ester, and a fluorescent dye. To produce light, the hydrogen per- oxide oxidizes the phenyl oxylate ester to produce phenol and an unstable peroxyacid ester. This unstable ester decomposes, resulting in an additional phenol molecule and a cyclic peroxy compound. The peroxy compound then decomposes to form carbon dioxide. As a result of these decompositions, energy is released to the dye, where the electrons jump to a higher energy level. As they return to their ground state energy, they release energy in the form of photons that we see as visible light. The light stick is simply a housing for the two solutions involved in the reaction and prevents the chemical reaction from happening until the two solutions are allowed to mix with each other. The hydrogen peroxide is kept in a small glass vial inside the solution of dye and phenyl oxylate ester. When you bend the plastic stick, the glass vial is broken and the two solutions begin to react with each other. Many factors determine how long the reaction will last. As a result, light sticks may produce light from several minutes to as long as several hours.