The “Chemical Kinetics” experiment was done to investigate the changes in the rate of reaction under the effect of concentration, temperature, and presence of a catalyst. It was determined that as the concentration of reactants and the temperature increases, the rate of the reaction increases as well. Also, the reaction was run by the presence of catalyst, and the rate of the reaction increased drastically in the presence of it. The order of the reaction with respect to each reactant was calculated to be: x = 1 [I-], y = 1 [BrO3-], z = 2 [H+] by the method of initial rates. The average rate constant was determined to be 26.7 M-3s-1, and the activation energy was calculated to be 49.6 kJ/mol.
The whole purpose…show more content… The reaction occurred under three different temperatures: 40ْ C, 10ْ C, and 0ْ C. The experiment in this part was carried out just like part one. In flask 1, 10 mL of 0.010 M KI, 10 mL of 0.0010 M Na2S2O3, and 10 mL of H2O were mixed. In flask 2, 10 mL of 0.040 M KBrO3 and 10 mL of 0.10 M HCl were mixed, and 3 drops of starch was added. Then, the two flasks were put in an ice bath and cooled to about 10ْ C. Afterwards, the two solutions were mixed together while in the ice bath with swirling until turning blue. The time was recorded. The reaction was done the same way for the other two degrees (0ْ C, 10ْ C). If the water needed to be cold, ice was added, and if hot water was needed, the water was heated.
In the third part of the experiment, the reaction was carried out in the presence of a catalyst. The influence of the catalyst on the rate of the reaction was investigated. Again, mixture 1 from part one was used. In flask 1, 10 mL of 0.010 M KI, 10 mL of 0.0010 M Na2S2O3 ,and 10 mL of H2O were mixed. In flask 2, 10 mL of 0.040 M KBrO3 and 10 mL of 0.10 M HCl were mixed, and 3 drops of starch were added. Also, one drop of 0.5 M (NH4)2MoO4, ammonium molybdate, was added to Flask 2 which acted as a catalyst. The two solutions were mixed until a blue color was formed and the stopwatch was stopped. All the