Catalyzing Substrate Concentrations

Ibraheem Murtaza, Neil Madadi, Autumn Coomes, Cameron

Buckman, Allison Wright

Abstract

• We performed this experiment to determine if a hydrogen peroxide (H2O2) concentration of 1.5% or 3% will catalyze faster.

• We used an enzyme catalase 2000 u/mL and 1.5% and 3% concentration of H2O2.

• We believed that 3% H2O2 concentration would catalyze faster, however, that is not what our results showed us. Our results showed that 1.5% H2O2 concentration catalyzes faster.

• Research shows that 3% H2O2 concentration does catalyze faster, therefore, we will need to do perform more trials to validate results.

Background• Other research showed that 3.0% hydrogen peroxide catalyzed faster

than 1.5% hydrogen peroxide due to the fact that higher concentrations are more reactive.

• We hypothesized that the 3.0% H202 concentration would catalyze faster than the 1.5%. After performing our designed experiment, we found that our hypothesis was incorrect. Although we designed our experiment based on those of other researchers, our results did not match the results of other identical experiments.

• That said, the fault was probably in some part of our experiment’s setup, whether it be a defective Vernier recorder or the presence of an unwanted substance in our flask.

• Our goal was to prove that 3.0% H202 catalyzed faster than 1.5% H202.

Hypothesis

• The Hydrogen Peroxide (H2O2) concentration of 3% would catalyze faster than the 1.5 %H2O2 concentration.

Materials• Computer with Vernier Logger Pro software• Labquest Mini• Stirrer and stirring bar• Ring stand• Clamp• 50 mL graduated cylinder• 125 mL Erlenmeyer flask• Vernier Pressure Sensor• Luer-Lock tubing• Rubber stopper • Micropipette with clean tips • 1.5% H2O2 solution

• 3% H2O2 solution• Catalase 2000 u/mL• Distilled water

Method• Attach rod and clamp to stand.• Attach clamp to 125 mL Erlenmeyer flask.• Plug in stirrer and place under the flask.• Connect Labquest Mini to Vernier Pressure Sensor and then connect to

computer.• Activate Vernier Logger Pro software on computer.• Put 50 mL of 1.5% H2O2 solution into flask.• Using the micropipette, add 100 uL of catalase 2000 u/mL to flask.• Add stir bar to flask.• Seal flask with stopper and connect Luer-Lock tubing to Vernier sensor.• Turn on stirrer to the 5th speed and start date collection on computer

for 200 seconds.• Repeat steps with 3% H2O2 solution.

Results

• The 1.5% concentration of Hydrogen Peroxide catalyzed at a faster rate because of the higher pressure created than the 3.5% concentration of Hydrogen Peroxide.

• The 1.5% concentration of Hydrogen Peroxide rose to a pressure of roughly 115 kPa before leveling out.

• The 3% concentration of H2O2 rose to a pressure of 110 kPa before leveling out.

• The 1.5% concentration had a rate of 0.053 kPa/sec, which is a higher catalyzing rate than the 3%, which had a rate of 0.028 kPa/sec.

• Recorded for 200 seconds

1.5% Concentration of H202 with Catalase 2000 u/mL

3% Concentration of H202 with Catalase 2000 u/mL

Discussion

• The catalyzation of the hydrogen peroxide occurred faster during the experiment containing 1.5% H2O2 rather than the 3% H2O2.

• Opposite results. • Some possible errors include: The pressure sensor connected to the laptop may have been leaking air out of a valve.• We could run the experiment again and check

to make sure no air is leaking.• This may produce more accurate results.

Conclusion

• The data produced from the experiment disproved the hypothesis, more trials needs to be done to confirm that the 1.5% concentration of H2O2 will catalyze faster than the 3% concentration of H2O2.

Citations

• A Level Notes. (nd). Factors Affecting Enzyme Activity. [accessed 26 January 2014]. Retrieved from http://alevelnotes.com/Factors-affecting-Enzyme-Activity/146?tree

• Worthington Biochemical Corporation. (nd). Introduction to Enzymes. [accessed 26 January 2014]. Retrieved from http://www.worthington-biochem.com/introbiochem/substrateconc.html