Preparation of Ethanol from Sucrose
Experiment #1 Preparation of Ethanol from Sucrose
Based on R. Weglein & C.L> Yau, CHEM 203 Experiments in Organic Chemistry II Laboratory, 5th Edition, 2006, p29-32.
Statement of Purpose: An aqueous solution of ethanol is prepared by the fermentation of sucrose. The percent alcohol is the resulting solution and the percent conversions of the sucrose are to be determined.
Introduction: Sucrose is a molecule containing glucose and fructose.
http://faculty.tcc.fl.edu/scma/phelpsj/experiments/ethanol.pdf
Balanced Equation: yeast yeast
C12H22O11(s) + H2O 4C2H5OH(l) + 4CO2
Table of Reagents and Expected Products:
Reagent | MW | # of moles | Volume and Mass | Properties | SucroseC12H22O4 | 342.2965 g/mol | 0.0500 mol | 10.75 mL17.134 g | d= 1.59 g/mL | WaterH2O | 18.015 g/mol | 5.55 mol | 100 g100 mL | d= 1 g/mL | EthanolC2H5OH | 146.07 g/mol | 0.2000 mol | 11.68 mL9.214 g | d= 0.789 g/ml | Carbon DioxideCO2 | 44.01 g/mol | 0.2000 mol | 8.802 g4452 mL | d= 0.0020g/mL |
Reference 1: http://wolframalpha.com accessed 12 June 12
Calculations:
Volume of sucrose = 17.1 g / 1.59 g/mL = 10.75 mL
Mass of water = 100 mL (1 g/mL) = 100 g
Moles of water = 100 g / 18.015 g/mol = 5.55 mol
1 mol sucrose=4 mol ethanol 1 mol sucrose=4 mol carbon dioxide
¼=0.0500mol/x 1/4=0.0500mol/0.2 mol x=0.2 mol ethanol
Experimental Procedure:
The procedure followed is given in Weglein and Yau, CHEM 203 Experiments in Organic Chemistry II Laboratory Manual; 5th Edition, Academx: Baltimore, MD, 2007, p29-32.
Results and Discussion:
mL Collected | Temp °C | 0 | 22.2 | 5 | 92.7 | 10 | 94.9 | 15 | 96.5 | 20 | 97.7 | 25 | 98.5 |
N20D=1.3569
% ethanol=34.8% from graph
Vethanol=25.05mL(0.348) = 8.717 mL ethanol
MassEtOH= 8.717mL(0.785g/mL)=6.843g
% conversion=(6.843g/9.214)100=74.27%
The graph depicted in Weglein and Yau shows that from the Refractive Index taken (1.3569) 34.8% ethanol was produced from sucrose.
Based on R. Weglein & C.L> Yau, CHEM 203 Experiments in Organic Chemistry II Laboratory, 5th Edition, 2006, p29-32.
Statement of Purpose: An aqueous solution of ethanol is prepared by the fermentation of sucrose. The percent alcohol is the resulting solution and the percent conversions of the sucrose are to be determined.
Introduction: Sucrose is a molecule containing glucose and fructose.
http://faculty.tcc.fl.edu/scma/phelpsj/experiments/ethanol.pdf
Balanced Equation: yeast yeast
C12H22O11(s) + H2O 4C2H5OH(l) + 4CO2
Table of Reagents and Expected Products:
Reagent | MW | # of moles | Volume and Mass | Properties | SucroseC12H22O4 | 342.2965 g/mol | 0.0500 mol | 10.75 mL17.134 g | d= 1.59 g/mL | WaterH2O | 18.015 g/mol | 5.55 mol | 100 g100 mL | d= 1 g/mL | EthanolC2H5OH | 146.07 g/mol | 0.2000 mol | 11.68 mL9.214 g | d= 0.789 g/ml | Carbon DioxideCO2 | 44.01 g/mol | 0.2000 mol | 8.802 g4452 mL | d= 0.0020g/mL |
Reference 1: http://wolframalpha.com accessed 12 June 12
Calculations:
Volume of sucrose = 17.1 g / 1.59 g/mL = 10.75 mL
Mass of water = 100 mL (1 g/mL) = 100 g
Moles of water = 100 g / 18.015 g/mol = 5.55 mol
1 mol sucrose=4 mol ethanol 1 mol sucrose=4 mol carbon dioxide
¼=0.0500mol/x 1/4=0.0500mol/0.2 mol x=0.2 mol ethanol
Experimental Procedure:
The procedure followed is given in Weglein and Yau, CHEM 203 Experiments in Organic Chemistry II Laboratory Manual; 5th Edition, Academx: Baltimore, MD, 2007, p29-32.
Results and Discussion:
mL Collected | Temp °C | 0 | 22.2 | 5 | 92.7 | 10 | 94.9 | 15 | 96.5 | 20 | 97.7 | 25 | 98.5 |
N20D=1.3569
% ethanol=34.8% from graph
Vethanol=25.05mL(0.348) = 8.717 mL ethanol
MassEtOH= 8.717mL(0.785g/mL)=6.843g
% conversion=(6.843g/9.214)100=74.27%
The graph depicted in Weglein and Yau shows that from the Refractive Index taken (1.3569) 34.8% ethanol was produced from sucrose.