Name:

Catalase Lab

Question:

Chose one question to investigate:

  1. What effect will decreasing the substrate (H2O2) concentration by 50% have on the reaction rate?
  2. What effect will decreasing the enzyme (catalase) concentration by 50% have on the reaction rate?

Background:

Source: Genevieve Nelson. Access Excellence Catalase Lab. On-line. © The National Health Museum. Accessed 3/20/2007

Mr. Rick says:

Hypotheses (predictions):

A prediction using the "If __ then ___, because ____" format is provided by the student.

Equipment:

  1. 10 ml graduated cylinder
  2. (2) test tubes
  3. petri dishes
  4. forceps
  1. 5 ml catalase solution (potato extract) in ice bath.
  2. hydrogen peroxide (H2O2). 3% standard dilution.
  3. 6 mm diameter filter paper discs

Procedures:

Contamination is an issue with this lab. Do not use your fingers. Use the forceps and wash the forceps after touching the catalase or H2O2 solution.

The student will create a procedure to:

  1. Measure the baseline catalase activity (undiluted solution).
  2. Dilute the catalase or substrate.
  3. Measure the catalase activity using the diluted solutions.

Generic Procedure for Measuring Catalase Activity:

  1. Fill a test tube with _____ ml of fresh H2O2 solution.
  2. Use the forceps to place a paper disc in the enzyme solution for _____ seconds.
  3. Use the forceps to place the disc on a paper towel for ____ seconds to drain off the excess enzyme solution.
  4. Use the forceps to place the disc at the bottom of the H2O2 solution.
  5. Measure and record the time it takes the disk to rise to the surface.
  6. Repeated trails: repeat steps 1 through 5 ______ times.

Data Tables

Student provided.

Conclusions

Student provided.