The Effect Of Varying Enzyme Concentration On The Breakdown Of Hydrogen Peroxide

Hydrogen peroxide will breakdown to oxygen and water in the presence of Catalase. The reaction will increase with increasing enzyme concentration when molecules of hydrogen peroxide are freely available. However, when molecules of the substrate are in short supply, the increase in rate of reaction is limited and will have little effect.

In this investigation, the variables that affect the activity of the enzyme, Catalase, were considered and controlled so that they would not disrupt the success of the experiment.

i) Temperature - As temperature increases, molecules move faster (kinetic theory). In an enzyme catalysed reaction, such as the decomposition of hydrogen peroxide, this increases the rate at which the enzyme and substrate molecules meet and therefore the rate at which the products are formed. As the temperature continues to rise, however, the hydrogen and ionic bonds, which hold the enzyme molecules in shape, are broken.

ii) pH - Any change in pH affects the ionic and hydrogen bonding in an enzyme and so alters it shape. Each enzyme has an optimum pH at which its active site be

In order to decide how varying the enzyme concentration affected the decomposition of hydrogen peroxide, the rate of reaction was measured. To do this accurately, the time taken for a specific quantity of oxygen gas (a product of the reaction) to be released was determined. This was achieved by observing the time taken for the manometer fluid to travel between the two marked fixed points as it was forced through the manometer by the rising gas. This was an accurate measure of how the enzyme concentration influenced the breakdown of hydrogen peroxide, as the quantity and speed of gas produced is dependant on the rate of reaction.

All measurements were taken so that the stopwatch was started once the rubber tubing was sealed and the stopwatch stopped once the manometer fluid had reached the base of the highest marked point. To judge accurately, the point at which the fluid reached the marked line, it was examined at eye level and the measurement taken when the bottom of the meniscus was lined up to the mark. This was the same for every reading.

Some topics in this essay:
Catalase Conclusion, Hypothesis Hydrogen, Observations Measurements, Suggestions Improvements, Safety Laboratory, Substrate Concentration, Inhibition Inhibitors, Concentration Provided, enzyme concentration, rate reaction, hydrogen peroxide, substrate concentration, active sites, substrate molecules, free active sites, free active, increasing enzyme, presence catalase, increase rate, increasing enzyme concentration, increase rate reaction, substrate short supply, decomposition hydrogen peroxide, Enzyme Concentration,