2I- (aq) + S2O82- (aq) ? I2 (aq) + 2SO42- (aq) The following rate data was collected by measuring the time required for the appearance of the blue color due to the iodine-starch complex. Trial [I-] [S2O82-] Reaction Time 1 0.040 M 0.040 M 270sec 2 0.080 M 0.040 M 138 sec 3 0.040 M 0.080 M 142 sec 1. In each trial, the blue color appeared after 0.0020 M iodine (I2) had been produced. Calculate the reaction rate for each trial by dividing the concentration of iodine formed by the reaction time. 2. Compare trials 1 and 2 to determine the order of reaction with respect to iodide ions. How did the concentration of iodide ions change in these two trials, and how did the rate change accordingly? What is the reaction order for iodide? 3. Which two trials should be compared to determine the order of reaction with respect to persulfate ions? What is the reaction order for persulfate? 4. Write the rate law for this version of the iodine clock reaction. Could the rate law have been predicted using the coefficients in the balanced equation? Explain.