The decomposition of hydrogen peroxide in an aqueous solution is a reaction of first order. It can be followed by titrating 10 ml. portions of reaction mixture at various times from the beginning of reaction against a standard solution of KMnO4. Volume of KMnO4 solution used in each case is proportional to the remaining concentration of HO2. H-20 From the following data calculate the rate constant of the reaction Time (seconds) KMnO4 solution used (ml) 0 22.8 600 13.8 1200 8.20