Definitions <ul><li>Incandescence – The emission of light due to heat. </li></ul><ul><li>Fluorescence and phosphorescence – The emission of light in response to radiation energy. </li></ul><ul><li>Laser Generation – The concentrated emission of light using stimulated emission. </li></ul>
Chemical Reaction: Light <ul><li>An outside source of energy excites atoms, causing them to release particles of light called photons. When you burn something, for example, heat energy causes the atoms that makes up the material to speed up, when the atom speeds up, they collide with each other with greater force. If the atoms are excited enough, the collisions will transfer energy to some sort of the atoms electrons. When this happens, an electron will be temporarily boosted to a higher energy level. When it eventually falls back down to its original level, it release some of its energy in the form of light protons. </li></ul>
Glow Stick: The chemical Reaction <ul><li>The chemical reaction in a glow stick involves several different steps. A typical commercial glow stick holds a hydrogen peroxide solution, phenyl oxalate ester solution and a fluorescent dye. This is what happens when the two solutions are combined… </li></ul>
Chemical Reaction Continued <ul><li>The hydrogen peroxide oxidizes the phenyl oxalate ester, resulting in a chemical called phenol and an unstable peroxiyacid ester. </li></ul><ul><li>The unstable peroxiyacid ester decomposes, resulting in additional phenol and a cyclic peroxy compound. </li></ul><ul><li>The cylic peroxiy compound decomposes to carbon dioxide. </li></ul><ul><li>The decomposition releases energy to the dye. </li></ul><ul><li>The electrons in the dye atoms jump to a higher level, then fall back down, releaseing energy in the form of light. </li></ul>
How it works! <ul><li>When you bend the plastic stick, the glass vial snaps open and the two solutions flow together. The chemicals react to one another and the atoms begin emitting light. The dye in the chemical solution gives the light its color. </li></ul>
<ul><li>Depending on which compounds are used the chemical reaction may go for minutes or hours. If you heat the solution, the extra energy will accelerate the reaction and the glow stick will glow brighter, but in a shorter time. They also come in different shapes and sizes. </li></ul><ul><li>If you want to preserve your glow stick for the next day, put it in the freezer. It wont stop the process but it will drag out the reaction. </li></ul>
How It Effects The Environment <ul><li>It’s believed that a glow stick is a better save of energy. It could be used as a light source to see in darkness rather than using a flashlight and using toxic batteries that harm our environment. Though, if the toxins from the glow stick spill out its very harmful to the human body if ingested. </li></ul>
Web Sites! <ul><li>Http://greenanswers.com/q/35530/products-shopping/manurfacturing-materials/how-are-glow-stick </li></ul><ul><li>http://www.pbs.org/kcet/wiredscience/story/55-glow_stick.html </li></ul><ul><li>http://answers.yahoo.com/question/index?qid=20061023091548AA9rLue </li></ul><ul><li>http://www.wisegeek.com/what-are-glow-sticks.html </li></ul><ul><li>http://chemistry.about.com/od/howthingsworkfaqs/a/howlightsticks.htm </li></ul>
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