Abstract
The purpose of this lab was to demonstrate the fermentation process of ethanol from the substrate sucrose. To make ethanol from sucrose two enzymes invertase and zymase were used. Vacuum filtration and fractional distillation were performed to get a more concentrated solution. The density of ethanol was .825 g/mL with a percent composition of 85% pure ethanol.
Introduction
Fermentation is a metabolic process in which an organism converts a carbohydrate such as starch or sugar, into an alcohol or an acid. One particular alcohol, ethanol is the least toxic of the alcohols and as such, has …show more content…
The end product ethanol inhibits the action of the enzymes in the yeast. Distillation preformed in order to get more concentrated solutions. Distillation is based on the differences in boiling points of the components of the mixture. Fractional distillation is used to separate the mixture giving 95% ethanol and 5% water. This distillation process allowed many condensation and vaporization to take place before the pure vapors finally entered a cooling condenser. The constant boiling mixture is called an azeotrope. Pure or 100%, ethanol is obtained by adding benzene to the water ethanol mixture and is called absolute ethanol. Treating the mixture with calcium oxide removes last traces of water, and a final distillation gave absolute …show more content…
The ethanol solution smelled of alcohol and yeast.
Instead of collecting the 10mL of distillate required, 7.8mL of distillate was obtained. The density determined was .825g/mL, when compared to the graph provided by the instructor the ethanol produced had an 85% final product. According to the graph the results were somewhat accurate, even through the ethanol produced did not have 100% it still fell within the desirable percentile.
Figure 1.3 This graph illustrates the percent composition of aqueous ethanol as a function of density at 20 C. As the density increase, the percentage of ethanol decreases. As previously stated the density was measured at 0.825g/mL when compared to the percentage of ethanol resulted in 85% ethanol.
Conclusion
Overall this experiment was successfully completed, after completion of this experiment one should have mastered a number of techniques. Based on the results of 85% ethanol percent composition, this experiment was somewhat accurate. With the use of fractional distillation, fermentation, and vacuum filtration the students made sure not to allow any other material in or out of the mixture. This experiment was an overall success and was executed with minimal