Step one of the Briggs-Rauscher oscillating reaction. This reaction is the combination of three colourless solutions: hydrogen peroxide; an acidic sol


Step one of the Briggs-Rauscher oscillating reaction. This reaction is the combination of three colourless solutions: hydrogen peroxide; an acidic solution of potassium iodate; and a solution of malonic acid, manganese sulphate and soluble starch. When all three are combined, the solution slowly turns amber as iodide reacts with iodate to form free iodine. When the iodide concentration is greater than the iodate, it very quickly reacts with the free iodine and starch to form a black colour. This slowly disappears as the malonate ions consume iodine faster than it is produced. This returns the iodide iodate ratio to the original value and the process starts again. This oscillation continues until all the malonic acid is used up.


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