Enzyme Catalysis Lab Materials at lab station Ring

Enzyme Catalysis Lab

Materials – at lab station Ring stand with burette Funnel Stirring rod Safety goggles Glass bowl for ice Small graduated cylinder Large graduated cylinder Sharpee Marker 20 small cups 3 large cups 4 syringes Piece of white paper Dropper Glass beaker Test tube holder (metal wire thing)

Materials – to pick up from center station - Ice - 1. 5% H 2 O 2 – 90 m. L - OVERNIGHT H 2 O 2 – 10 m. L - Catalase – 20 m. L (KEEP ON ICE!!) - 1 M H 2 SO 4 – 100 m. L (careful – ACID!) - KMn. O 4 – 25 m. L (put in burette!)

Finding Baseline: Procedure 1. First you need to set up the burette. Using the funnel, fill the burette with KMn. O 4. Make sure not to fill it past the measuring lines because you will need to be able to read it. 2. Put l 0 m. L of 1. 5% H 2 O 2 into a clean small cup. 3. Add 2 m. L of H 2 O (instead of enzyme solution). 4. Add 10 m. L of H 2 SO 4 (1. 0 M)(ACID!). 5. Mix well. 6. Remove a 5 m. L sample. Place this 5 m. L sample into a different small cup and assay for the amount of H 2 O 2 as follows: Place the beaker containing the sample (5 m. L) over a piece of white paper. Note the INITIAL level of KMn. O 4 (potassium permanganate; purple color) in the burette to start and record that information in Table 1. 1 below. Use the burette to add KMn. O 4, one drop at a time, to the solution until a persistent pink or brown color is obtained. Once the color stays brownish and does not return to clear, stop adding the KMn. O 4 and note the FINAL level. Record that information on Table 1. 1. Remember to gently swirl the solution after adding each drop. Check to be sure that you understand how to read the burette.

So basically…. 10 m. L H 2 O 2 + 2 m. L H 2 O + 10 m. L H 2 SO 4 22 m. L Take a 5 m. L SAMPLE and then titrate it using the KMn. O 4

Finding Amount of H 2 O 2 Decomposed Do the exact same steps as the baseline procedure except use OVERNIGHT H 2 O 2 instead of fresh.