Luminol Research Paper

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Luminol is a yellow, crystalline compound that has the molecular formula C8H7N3O2. Luminol has unique properties because it exhibits chemiluminescence in low light conditions when exposed to an oxidizing agent. Chemiluminescence occurs when a chemical reaction releases energy in the form of photons. It usually occurs when an oxidizer such as peroxide reacts with an other molecule. The product produced in the reaction is in the excited electron state. When it falls to the ground electronic state, energy is emitted as a photon, which is why light is observed. Luminol can be synthesized by reaction 3-nitrophthalic acid with hydrazine to form 3-nitrophthalhydrazide. This compound is then reacted with sodium hydrosulfite to form luminol. To exhibit its chemiluminescence, luminol is reacted with an oxidizing agent which pushes electrons up to a higher energy excited state. When the electron drops back down to the lower energy ground state,
Around 1902, when luminol was first synthesized, scientists noticed that it exhibited a blue glow in the presence of other compounds. Later on, it was found that the luminol reaction occurred in the presence of blood. Its use in crime scenes was first implemented by German forensic scientist Walter Specht in 1937. When the luminol solution is sprayed, the iron present in hemoglobin in blood catalyzes the reaction to produce a blue glow. This is used because in certain situations, there may be too little blood present at a crime scene to be able to be seen. It can also help when a suspect had attempted to “clean up” the blood after committing the crime. In these cases, luminol can be used to see any evidence of blood that cannot be seen with the naked eye. The glow from the reaction only lasts for about thirty seconds and requires dark conditions to be able to see, but investigators are able to document it in

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