'Determination of Rate Law Essay\r'

'Abstract: A outcome containing potassium iodide was mixed with a enthalpy hydrogen peroxide theme to set up the calculate natural law for the answer between atomic number 1 peroxide and potassium iodide at means temperature and the energizing energy, Ea, of the above reaction. Potassium iodide and hydrogen peroxide react according to the following equation: We found the experimental evaluate law for this reaction to be and the energizing energy of the reaction was calculated to be and the Arrhenius pre-exponential factor (A) of . Introduction All chemical reactions require some minimum bill of energy to transform the reactants into products.\r\nThe rate of the reaction is the rate at which the products are bring into being from reactants. At constant temperature, the rate of a chemical reaction is constant and tush be determined experiment in ally utilize the general rate law . variable the temperature at which a affairicular reaction takes countersink changes t he activation energy of the reaction at the different temperatures. Using a transformed version of the Arrhenius equation the esteem of for the reaction and the Arrhenius pre-exponential factor can be determined graphically. Methods There were dickens terminations winding in this experiment: Solution A comprised of 5.\r\nOmL buffer (to stabilize [H+]), 0. 3M KI (a antecedent of I-), starch (indicator for I2), 0. 02M sodium thiosulfate (source of thiosulfate ion), and distilled weewee (to establish the total volume to 40. 00mL), while ascendent B contained 0. 1M hydrogen peroxide. In the starting time part of the experiment, we determined the rate law as follows: We prepared final results A and B for apiece trial using the recommended volumes in hold over 2 of the lab manual.\r\n afterwards preparing the answers, we utilize separate thermometers to record the temperature of each solution to the nearest 0. 1, ensuring that both solution temperatures did not deviate by much than 0. 5. The data obtained was enter as put over 1. after recording the temperatures, my partner started the timekeeper on her phone while I poured solution B into the flask containing solution A. The end of the reaction was signaled by the establishment of a blue iodine-starch complex in the flask. The amount of iodine produced was calculated using the amount of thiosulfate (limiting reagent in the thiosulfate-iodine reaction) in the solution.\r\nAfter performing all five trials, the measure out obtained for the first three trials were used to create Table 1a below. These set were then plan using Graphical Analysis and rationalise fitted to determine the order of the reaction with remark to iodide as shown on variant 1a. Table 1b was also created using the economic values for the coda three trials, then plot of landted on a graph (as shown on Figure 1b) to determine the order of the reaction with reckon to hydrogen peroxide and two values for the rate constant, . \r\nThe values for p and q were move to the nearest integer and the average of the two values was then calculated to be resulting in the rate law for the of In the second part of the experiment, we determined the activation energy for the decomposition of hydrogen peroxide using potassium iodide by performing runs similar to part 1, but variable temperatures at which the reaction takes place. For each run, solution A and B were prepared using the recommended values from the lab manual.\r\nWe then place both solutions in an screwball bathe (for the first 2 runs) and in a water bath (for the remaining runs) to rise their temperatures to the same values as that of the water/ice in the bath. We also used the temperature values suggested in the lab manual. When needed, we increase the temperature by heating the hot casing on which we placed our bath of adding ice cubes into the bath. Once the thermometers in each solution and that in the bath reached the desired value, I simultaneo usly noted the time on the lab clock and poured solution B into the flask containing solution B.\r\nI recorded the time from when I poured solution A into B to when I noticed a color change from colorless to purple. I then used the data obtained to plot a graph of ln(k) against the reciprocal of the temperature for all the six runs, plus the average value of k and temperature calculated from the first part of the lab. This graph was then used to determine the activation energy, Ea and the Arrhenius pre-exponential factor, A. We report an A value of and an activation energy value of 56. 80kJ/mol. This compares to divinatory value of 56. 5kJ/mol at 0. 53% difference.\r\n'