The aim of this experiment is to find the effect of varying temperature on the rate or reaction between ethanedioic (oxalic) acid and an acidified solution of potassium permanganate:
5 (COOH)2(aq) + 6 H+ + 2 MnO42-(aq) à 2 Mn2+(aq) + 10 CO2(g) + 8 H2O(l)
Initially the reaction mixture is purple in colour due to the presence of the permanganate ions but it will turn colourless as soon as they are used up. This colour change allows us to follow the course of the reaction
Effect of temperature on rate of reaction – pupil guide