Enzyme Catalysis

ABSTRACT: This lab allows us to observe the conversion of hydrogen peroxide (H2O2) into water and oxygen gas. An enzyme known as catalase facilitates this decomposition reaction. The catalase enzyme acts as catalysis, helping lower the energy needed to activate the reaction while the enzyme itself is not affected. Catalase is a digestive enzyme used to break down hydrogen peroxide, which is a normal byproduct of cellular respiration. The reaction could take place without the help of catalase, but it would happen a lot more slowly because more energy is needed for the reaction.

This lab demonstrates the effect the enzyme catalase has on the rate of the decomposition reaction of hydrogen peroxide into water and oxygen gas. It would be expected that extreme temperatures or pHs would denature the enzyme, directly affecting the rate of reaction. It is also safe to assume that the rate of reaction would be higher in the preliminary seconds of the reaction due to higher substrate concentrations. The rate of reaction would eventually slow when most of the substrate (H2O¬2) has decomposed.

In this experiment, catalase serves as the enzyme, hydrogen peroxide acts as the substrate, and sulfuric acid serves as the inhibitor, eventually stopping the reaction. HYPOTHESIS: If environmental conditions are ideal for the reaction, then the enzyme catalase will decompose H2O2 at a fast and efficient rate. CONCLUSION: The catalase enzyme aided in the reaction of decomposing hydrogen peroxide into water and oxygen gas. However, enzymes are environmentally sensitive, so we were able to see direct effects on the reaction when the catalase solution was heated, denaturing it and reducing the results of the reaction.

As for the effect of time and the catalase on the rate of reaction, we were able to see a high rate of reaction toward the beginning of the reaction, but it slowly leveled out when more of the H2O2 had decomposed. The sulfuric acid served as an inhibitor ending the reaction (by denaturing the enzyme catalase) for our experimental purpose; but, in the body the enzyme is reusable and the reaction occurs spontaneously as a common metabolic process.