Make your own free website on Tripod.com

Catalase Lab Extension Proposal

The lab proposed will investigate temperature and its effects on catalase.

Materials

  1. Hydrogen Peroxide (1.5%)
  2. KMnO4 (2%)
  3. H2SO4 (1M)
  4. Titration buret
  5. Pipets and/or graduated cylinders
  6. Hot plate or Bunsen burner
  7. Large beaker for use as boiler (indirect heating) (500mL or 1L)
  8. Thermometer
  9. Paper plates with scissors and tape to modify it to cover the coffee cup better(cover for reaction area)
  10. A 250mL beaker (stabilizer for styrofoam cups)
  11. Styrofoam cups (at least 3, double insulated reaction area, hot liquid storage)
  12. Flasks (for titration)
  13. Couple small beakers to heat reactants in double boiler

Procedural Notes

  1. Use 20mL of hydrogen peroxide (thus 2mL of catalase and 20mL of sulfuric acid) to minimize losses due to atmospheric convection
  2. Establish baselines of hydrogen peroxide loss due to heating and handling.
  3. Attempt to compensate for heat of reaction and the different temperature of the catalase if at all present

Data Collection Proposed

All temperatures should have a baseline taken. Temperatures 10, 20, 30, 40, and 50 degrees celsius should be tested along with additional tests to find the true effecient point of the catalase (hypothesized to be about 32°C). KMnO4 titration will be used to find out the remaining hydrogen peroxide after 20 seconds. Additional runs at 60 seconds are possible if 20 seconds reveals too little data at the extreme points.

Procedure

Reaction in coffee cup

  1. Heat measured hydrogen peroxide and sulfuric acid
  2. Place in reaction vessel and measure temperature
  3. Add catalase and cover and stir
  4. Time Interval
  5. Add sulfuric acid and stir
  6. Place in titration container and titrate

Alternate

Reaction in flask in water bath of proper temperature

  1. Measure hydrogen peroxide
  2. Place in beaker (or flask) which is in water bath of the proper temperature, stir and wait until desired temperature has been attained
  3. React with catalase
  4. Time then add sulfuric acid
  5. Remove from bath and titrate.

This procedure does not require the styrofoam cups and will potentially maintain a better constant temperature over longer time intervals. It will also effectively get rid of heat of reaction.