Potassium Chlorate - Nishtha Kumar

 

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Have you admired all the different colors of the fireworks and wondered where they come from? The beautiful violet/pink color in the earliest fireworks came from a chemical known as potassium chlorate (KClO₃). Interestingly, KClO₃ is a white crystalline powder and when combined with silver fulminate it produces the crackling and popping noise of the fireworks (6). KClO₃ is only used in fireworks and explosives; it is also used in many high school labs as an inexpensive source or oxygen gas (6). This is because the KClO₃ breaks down very rapidly when heated to high temperatures, ultimately producing oxygen gas and KCl. It is also used as a disinfectant and in safety matches. Because chemistry is all about unexpected experiments, imagine what would happen if this explosive material were to be combined something as common as sugar. Because potassium chlorate is an oxidizer (removes electrons from another reactant in a chemical reaction) it reacts vigorously with sugars (easily oxidized), resulting in a big pink/violet colored explosion (3). The chemical reaction between KClO₃ and sugar is worth a watch. KClO₃ production starts with electrolysis of sodium chlorate (8). The resulting solution is then reacted with potassium chloride, creating potassium chlorate. Because KClO₃ reacts vigorously with many substances, it should be handled with extreme care. The chemical should be stored away from the combustible materials (2). Also, consumption of KClO₃ either by ingesting or inhaling could result in many health problems such as severe burns producing toxic gases, irritation, nausea and even death (2). Because KClO₃ reacts spontaneously and energetically, its usage in explosives and fireworks has been banned. Alternatively, potassium perchlorate is used in fireworks, producing the same effect as KClO₃ (6). Therefore, next time you see the colors of the fireworks, do not forget to admire the chemistry behind it.