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1.) Calculate and report with appropriate units the concentrations of I-, S2O82- in each of the experimental data test tubes and the initial rate for each of the experimental data sets. For potential full marks, show a sample calculation for how to find the concentration of I-, S2O82-, an initial rate.

2.) Calculate the rate law or rate equation based on your set of experimental data. For potential full marks you should show the calculations or explain your methodology that you used to determine the rate law.

3.) Calculate and report the value and units of k for each of your experimental data sets. For the potential of full marks, please show a sample calculation for one of the experimental data sets.

4.) Determine the activation energy (Ea) and Arrhenius pre-exponential factor (A or ρ) for the reaction. You must show your calculations.

5.) Based on the mechanism proposed in the ‘Data Sheets’ section of your lab manual, sketch the reaction profile. Properly label the profile and include the identification of mechanistic steps, location of the activation energies (values not required), Lewis structures of the reactants, intermediates and products in the appropriate locations.

Data Information supplied:

Part A: Average Experiment 1 = 24.1 degrees Celsius 229 Time Seconds

Part A: Average Experiment 2 = 24.1 degrees Celsius 436 Time Seconds

Part A: Average Experiment 3 = 24.1 degrees Celsius 523 Time Seconds

Part B: Average Experiment 1 4.1 degrees Celsius 1186 Time Seconds

Table 1: Grid indicating the solutions to add for each initial rate experiment:

	Initial rate experiment 1	Initial rate experiment 2	Initial rate experiment 3
Add first	10.0 mL NaI(aq) 5.0 mL Na2S2O3(aq) 1.0 mL starch(aq)	10.0 mL NaI(aq) 5.0 mL Na2S2O3(aq) 5.0 mL Na2SO4(aq) 1.0 mL starch(aq)	5.0 mL NaI(aq) 5.0 mL Na2S2O3(aq) 5.0 mL NaCl(aq) 1.0 mL starch(aq)
Add last, start timer	10.0 mL Na2S2O8(aq)	5.0 mL Na2S2O8(aq)	10.0 mL Na2S2O8(aq)

 

Part A: Determination of rate law

1. Collect the following solutions in separate small, clean, and dry beakers (label them!):

                                15-20 mL of 0.10 M Na₂SO₄                  100 mL of 0.10 M NaI                       

                                15-20 mL of 0.10 M NaCl                 100 mL of 0.10 M Na₂S₂O₈

                                11-12 mL of starch solution              55 mL of 0.0050 M Na₂S₂O₃