LIGHTSTICKS “Snap” a lightstick and watch it glow! This chemiluminescent reaction produces light, but no heat. Bending the flexible outer tube breaks an inner glass tube, allowing the contents of both tubes to mix and react as shown in the illustration. Energy is transferred to the dye molecules. Some of the electrons in the dye molecules are raised to an excited state; when the electrons fall to their original state, they give off light. Reference: Marsella, G.B.C. Chemiluminescence, the Cold Light. ChemMatters, October 1995, pp. 12–15.
