Chemical Reactions: Glow Sticks Abraham Torres, Kevin Wakefield, and Allison Woods CHM110 January 21, 2013 CHERYL BURLEIGH
Development of the Glow Stick • Modern glow stick was invented by Herbert Richter and Ruth Tedrick. A patent was filed in March of 1973 and awarded in June of 1974. • Glow sticks were developed by the United States Navy.
Practical Applications of Glow Sticks • Military Use • Entertainment • Camping • Recreational Diving • Disaster and Emergency Situations
What is a Glow Stick? • Plastic casing containing isolated chemicals. • Inner glass vial contains hydrogen peroxide. • Phenyl oxalate and fluorescent dye solution. • Hydrogen peroxide solution. • Isolated chemicals mix triggering an exothermic reaction that generates light. This is known as Chemoluminescence.
Chemical Reaction Behind the Light • Glow sticks are activated when the isolated chemicals hydrogen peroxide and diphenyl oxalate react, releasing phenol and cyclic peroxide. • Peroxides are an ideal reactant because the bonds between the oxygen atoms are easily broken releasing energy. • The cyclic peroxide then interacts with a fluorescent dye molecule releasing 2 molecules of carbon dioxide and exciting the electrons of the dye, it is the fluorescent dye that responsible for the color the glow stick. When the electrons relax, a photon of light energy is released.
Fluorophores: The Colors Behind the Light Part 2 Example 2 Example 1
Summary • Glow sticks were developed by the United States Navy and was awarded a patent in 1974. • The glow stick has many practical applications. • A glow stick is a single use short term light source that is contained within a plastic tube. This tube contains isolated chemicals and when mixed together, the chemical reaction that follows produces light energy. This is known as Chemoluminescence. • Chemoluminescence is an exothermic chemical reaction. • Fluorophores determine the color of the light emitted.
References • About Chemistry (n.d). Glow Stick Chemical Reaction retreived 1/17/2013 from http://chemistry.about.com/od/imagesclipartstructures/ig/Chemical- Reactions/Glowstick-Chemical-Reaction.htm • Helmenstine, A. M. (n.d.). Light Stick Colors. Retrieved from http://chemistry.about.com/library/weekly/aa031703a.htm • Light made through chemical reactions: Chemoluminescence. (n.d.). Retrieved from http://www.webexhibits.org/causesofcolor/4AD.html • United States Patent Office. (n.d.). United States Patent 3,819,925. Retrieved from http://patft.uspto.gov/netacgi/nph- Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2 Fsearch- bool.html&r=1&f=G&l=50&co1=AND&d=PALL&s1=3819925.PN.&OS=P N/38199 25&RS=PN/3819925 • Welsh, E. (2011). What is Chemoluminescence? Retrieved from http://www.scienceinschool.org/repository/docs/issue19_chemilumine scence.pdf