Redox Reaction Lab Report

Introduction:

Enzymes are proteins that function as catalysts, meaning that they increase the speed of a reaction without being changed themselves. The enzyme has two main jobs in a reaction that cause the reaction to increase. The first job is to bring substrates (the substances that the enzyme will be reacting on that bind to the active site in the beginning a reaction) together in an orderly fashion so that they can interact during the reaction. It’s second job is to decrease the energy needed for a reaction to take place. These tasks can be completed more efficiently in specific temperatures or with specific pH levels. The speed of a reaction can increase as temperature increases. This is because heat is a representation of kinetic energy:

This reaction occurs through both oxidation and reduction. Oxidation is the process of a compound losing electrons by binding with oxygen. Reduction occurs when a separate compound accepts these electrons. In this particular experiment, the enzyme peroxidase, which is specified to break down hydrogen peroxide, will be used to catalyze the redox reaction. The substrates will be reduced guaiacol and hydrogen peroxide (H2O2). This reaction will produce oxidized guaiacol, oxygen gas, and water. In the oxidation of guaiacol it will change colors, this is what shows the reaction has occurred. To monitor the reaction, a spectrophotometer will be used that will measure the absorbance of light. If the substance is a darker color, it will absorb more light, and if it is lighter it will absorb less light. In addition, the enzyme and substrate will be tested with different levels of pH and different temperatures in order to demonstrate if the reaction will improve or not based on these

This test tube lacked hydrogen peroxide in order to keep the reaction from occuring. In two test tubes labeled “Substrate”, we mixed 0.2 ml of hydrogen peroxide with 0.1 ml guaiacol and 4.7 ml of distilled water. We also labeled two test tubes “enzyme” using a glass marking pen and filled them with 1.0 ml of turnip extract and 4.0 ml of distilled water. After the test tubes were prepared, we put the blank test tube into a cuvette and put it into the spectrophotometer in order to zero it out. While one group member set the spectrophotometer to zero, another mixed one enzyme test tube with one substrate tube and observed a change in it’s color. After we set the spectrophotometer to zero, we mixed the second enzyme with the second substrate and promptly poured it into a clean cuvette to then be put in the spectrophotometer and record the absorbance at zero seconds, and again every thirty second for three