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Kevin Champagne10/5/2018Period 5Determination of Concentration by Oxidation-Reduction TitrationPurpose:This experiment is designed to determine the concentration of hydrogen peroxide in a drugstore bottle by titrating it with standardized KMnO4. Pre-Lab Questions:1.In this experiment we are using a graduated cylinder and a buret to measure precise volumes. Additionally, a flask is also useful for measuring precise volume.2.8H++ MnO4-+ 5e-→ Mn2++ 4H2O (The Mn goes from a +7 charge to a +2 charge)3.H2O2→ O2 + 2H++ 2e-(The oxygen goes from a -1 charge to a neutral charge)4.The two half reactions have a common multiple of 10e-, meaning that 10 mol e- are transferred in the balanced redox reaction.5.Fe+2→ Fe+3+ e-6.5e-+ 8H+ + MnO4-→ Mn2++ 4H2O (5 mol e-are transferred in this reaction)7.Perhaps copper could work, since it has both +2 and +3 oxidation states.8.We know that there is one MnO4-ion in potassium permanganate, so the mol ratio is 1:1. Thus,a.xmol MnO4-/0.0201 L = 0.020 Mb.x =0.0004 mol MnO4-9.