Investigating the Kinetics of the reaction between Iodide ions and Peroxodisulphate (VI) ions
By the use of an Iodine clock reaction I hope to obtain the length of time taken for Iodine ions (in potassium iodide) to react fully with Peroxodisulphate ions (in potassium Peroxodisulphate). I will do three sets of experiments changing first the concentration of iodide ions, then the concentration of Peroxodisulphate ions and finally the temperature of the solution in which the reaction is taking place. From these results, I hope to draw conclusions as to the effects of these changes to the environment of the reaction on the rate and also determine the order of the reaction and the activation enthalpy.
Making up standard solutions 1. Weigh out appropriate amount of chemical in weighing boat and record mass. 2. Tip contents into beaker and record weighing boat mass. Subtract this from original mass to give the actual mass of substance in solution 3. Add distilled water and stir using a glass rod until substance has fully disolved. 4. Pour solution into volumetric flask through funnel and using distilled water rinse beaker, glass rod and funnel into the volumetric flask so that no solution remains on any apparatus used. 5. Add distilled water up to the mark
It is important to ensure that all apparatus is rinsed otherwise the mass recorded of the amount of substance in the solution is inaccurate and the concentration is unknown.
From the mass recorded of each substance one is able to work out the exact concentration of the solution using the following equations:
Mass (g) Moles . RMM = Moles Volume of solution (dm3) = Concentration
Rate of reaction experiement (concentration) 1. Fill three burettes using a funnel with each of the solutions and in the remaining two: water and freshly made starch solution. Ensure each funnel is removed and the burette