Determination of Kinetic Parameters in the interaction between Hydrogen Peroxide and Chromium (VI) Oxide

Abstract

The kinetics of the interaction between Chromium (vi) Oxide and Hydrogen Peroxide were studied. Hydrogen Peroxide is marketed in the form of an aqueous solution and being a limiting reagent in this research, its concentration was first determined by titration with standard solution of Potassium Permanganate (0.02M) before its subsequent utilization. The effect of varying mass of CrO3 on the decomposition of fixed volume of H2O2 was studied by measuring the volume of oxygen evolved and the time taken for the evolution to cease. Similarly, the effect of the decomposition of varying volumes of H2O2 with fixed mass of CrO3 was also studied. At the end of the reaction, the volume of O2 evolved and the time taken for the evolution of O2 were equally recorded. The results of the above decompositions indicated that CrO3 acted as a catalyst. The decomposition of H2O2 catalyzed by CrO3 was found to be a first order reaction. This was determined through the measurement of the half-life of the same reaction. The results of the titrations of acidified solution of H2O2 against KMnO4 solution at different time intervals carried out at 35 o C and 45 o C were used in calculating the specific rate constants and were found to be 3.11 x10 -2 and 6.11 x 10 respectively. Furthermore, the values of the specific rate constants obtained were used in calculating the activation energy of the reaction (Ea) which was found to be 13.49075 kcal.