Formal Lab Organic Chem

Suzi Warden

4.10.09

Chem 111

Formal Lab Report

I. Introduction and Background.

Enzymes are what the body and other living organisms uses to catalyze chemical

reactions. They are proteins and very effective catalysts. They have very large molecular weights and cannot be measured in units because they are very hard to purify, so they are measured by their activity[1].

Invertase is an enzyme that converts sugar (sucrose) in to D-Glucose and D-fructose. Since these monosaccharides are called invert sugar, that’s how invertase is named.

Equation 1: Hydrolysis of sucrose:

C12H22O11 + H2O (invertase)=> C6H12O6 + C6H12O6

The purpose of this experiment is to see how the concentration of an enzyme affects the speed of an an enzymatically catalyzed reaction.

II. Methods

In the first part of the experiment, a control was made to be a standard for finding the concentrations of solutions in the second part of the experiment. Solutions with different concentrations of 0.01M invert sugar ranging from 0-1.5mL and water ranging from 1.5-0mL with consistent amounts of 0.3M Sucrose (1.0mL), and 0.05M Acetate Buffer (0.5mL) were reacted with DNSA to produce a reddish brown derivative.

Equation 2: Formation of DNSA derivative:

3D-Glucose + Soduim 3,5-dinitrosalycilate (DNSA) + H2O (pH4.7)=> 3D-Gluconate + Sodium 3-amino-5-nitrosalicylate

Then those test tubes were put into a spectrometer to measure the absorbance of light. The absorbance can then be graphed as a function of concentration. This graph will be used to find the concentrations of unknown invert sugar solutions by their absorbencies.

In the second part of the experiment, we tested unknown concentrations of invertase. Six test tubes (labeled 1-6) were set up with amounts of H20, ranging from 1.5-0.5mL, amounts of invertase...