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The sucrose and potassium chlorate demonstration has been modified to provide a safer ignition method and to increase its spectacular nature. Ignition is best accomplished by placing a safety match head in the mixture and igniting the safety match with a butane lighter of the type used for outdoor grills. A brilliant rocketlike flame can be produced by carrying out the reaction in a short piece of capped plumbing pipe. The plumbing pipe is concealed in a sand bath, which has the advantages of limiting any suggestion of a pipe bomb to the audience and catching any ejected material. We determined that reaction mixtures corresponding to stoichiometric molar amounts of the reactants produce the least ash. Brightly colored flames also can be produced by mixing the appropriate colorizing salts and powdered polyvinyl chloride with the reaction mixture. Recipes for reaction mixtures and for colorizing salt mixtures are presented.
To assess the degree of exposure to colorizing salts by an audience, the percent of metal salt that is vaporized was investigated. Mixtures containing barium chloride were analyzed using the standard sulfate precipitation method. It was determined that 23 percent of the barium ion was vaporized during the combustion reaction. This means that the demonstration must be conducted in a hood.
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