Glowsticks!Many of you would have had the experience of snapping glow sticks before a party. But what actually happens inside the glow stick when it snaps is a mystery for most people. What is happening inside a glow stick when it is activated? Why does it only glow when we bend it? In today's meeting, we investigated the chemistry behind glow sticks. The structureGlow sticks actually contain two separate compartments, with two different chemical solutions. One solution, in the case of most glow sticks, contains a diphenyl oxalate compound which is contained within an inner glass cylinder. The other solution is hydrogen peroxide. the reactionOnce you snap the glow stick, the glass cylinder breaks and the two different solutions get mixed. The diphenyl oxalate is oxidized by the hydrogen peroxide, producing the unstable compound 1,2-dioxetanedione (a.k.a. cyclic peroxide). The cyclic peroxide decomposes into carbon dioxide, releasing energy as it does so - which is light! chemiluminescenceThe electrons in dye molecules absorbs the energy given off by the decomposition of cyclic peroxide. This causes the electrons get promoted to an excited state. When the electrons fall back to their ground state, they lose their energy in the form of photons of light. This process is known as chemiluminescence, the emission of light as a result of a chemical reaction. More info on glowsticks and CHEMILUMINESCENCEvideo by MIT K12 Videos (http://www.k12videos.mit.edu)
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