1. Enzyme Catalysis with Catalase

2. Key Notes From Lab Handout • Enzyme: Catalase (from beef liver) • Substrate: H2O2 (hydrogen peroxide) • Stop Reaction: use sulfuric acid (H2SO4) • Quantify Amt. of H2O2 left: titrate in KMnO4 (potassium permanganate) • Baseline: Starting total amount of H2O2 • FOUR ways enzyme activity can be altered: • Salt concentration (salinity) • pH (acid/base concentration) • Temperature • Activators & Inhibitors

3. Lab #3- Enzyme Catalysis w/Catalase Three Parts to the lab: • Establish Baseline Amount of H2O2 • Uncatalyzed Decomposition of H2O2 • Time Trials w/Catalase to determine Rxn rate • Procedure: • 10 ml H2O2 in a beaker • 1.0 ml (H2O or Catalase) • 10 ml 1 M H2SO4 • Mix well • Take a 5 ml sample and titrate in KMnO4 • Read Initial and final measurements on buret • Record Data

4. Uncatalyzed data • Final reading: 11.2 ml • Initial reading: 8.1 ml • Amount of KMnO4: 3.1ml

5. Sample Data Set I

6. Sample Data II

7. Conclusion Questions to Consider • Determine the amount of H2O2 in moles using the chemical equation on pg. 22 and your amount of H2O2 after 180 sec. • From Question #6, Choose two factors that can affect the rate of enzyme-catalyzed reaction of Catalase. Draw a predicted graph for each reaction. • Name two organisms that could be used to determine the reaction rate of an enzyme. • List two major sources of error and one suggestion on how to improve the lab. What would you do differently?