Monday & Wednesday 7:40-10:30
Experiment #2 – Kinetics of the Decomposition of Hydrogen Peroxide Introduction: Chemical reactions are dependent upon two factors: temperature and concentrations of substance. We can monitor the rate at which a chemical decomposes or the rate at which a chemical substance appears. In this experiment we will be measuring the rate of decomposition of hydrogen dioxide with the following reaction:
2 H202 (aq) 4 2 H20 (l) + 02 (g)
We can trap the oxygen gas created into a container thus showing the extent of the reaction and this will show the rate in which oxygen is created and how the rate will change when we use different initial concentrations. We do use a catalyst in this reaction to speed up the process and lower the activation energy needed to run the reaction. The catalyst is the Iodide ion that will be used in the form of potassium iodide (KI). Results at the end of the trails will be used to compose a rate of law for the reactions. This law will show the “dependence of the rate on the concentration of both H202 and I-. The rate of reaction equation is as follows: Rate of reaction = k [H202]M [I-]N
The value of m and n will be calculated from the various runs of the experiment holding either H202 at constant concentration or holding I- at constant concentration Experiment: My lab partner and I first assembled the apparatus that we were to use according to the sample that was used to show us how to conduct the experiment. We added room temperature water into the leveling bulb and filled until the bulb was about half way filled with water. I adjusted the ring so that I was able to freely move the leveling bulb during the experiment. After the apparatus was set up we proceeded to get a 250mL Erlenmeyer flask to place our solution in. The solution consisted of 10mL of .10 M KI and 15mL of distilled water. This solution needed to be bath temperature so we obtained a plastic bath and put luke warm water in it...