Catalyst race
Objective: Compare the efficiency of three different catalyst in the decomposition of hydrogen peroxide
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Laboratory materials
3 50 mL graduated cylinders
3 25 mL graduated cylinders
Plastic container to run the experiment
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Reagents
Hydrogen peroxide (H2O2) at 15%
Manganese dioxide (MnO2) Iron (III) oxide (Fe2O3)
A small piece of potato
Dish soap
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Safety
Don't forget the gloves, lab coat, and safety goggles!!!
Discard the waste in a specific container.
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Questions
What is it observed when the hydrogen peroxide is added?
Do all catalysts behave similarly?
Procedure
- Place the three 50 mL graduated cylinders tubes in line inside the plastic container and add a bit of dish soap to each one.
- Add a different catalyst in each graduated cylinder
- Measure 25 mL of hydrogen peroxide at 15% in each 25 mL graduated cylinder and add them, as simultaneously as possible (preferably with two people), to the different catalysts to compare their activity.
- Move away quickly!
Theoretical explanation
A catalyst is a substance that alters the rate of a chemical reaction without being consumed itself. In this experiment, the different catalysts accelerate the decomposition of hydrogen peroxide into oxygen and water. The more effective the catalyst, the faster the release of oxygen, and therefore, more foam is formed. Manganese dioxide is the fastest, followed by the potato, which reacts much slower. With iron(III) oxide, foam production is barely noticeable.
The reaction that takes place is:
2 H2O2 2 H2O + O2
This reaction can be catalyzed by different transition metal compounds as well as by peroxidase enzymes present in some living organisms.
