Academic Subjects
Chemistry
General Chemistry
Chemical Reactions
Theoretical Yield Of Ethanol

Determine the theoretical yield in grams of ethanol when 833 g of glucose is used according to the following fermentation reaction

C6H12O6(aq)    2 C2H5OH(l) + 2 CO2(g)



We already have our balanced equation, so let's find the molecular weight of glucose and ethanol

Glucose C6H12O6

C = 12.01 g/mol (6) = 72.06 g/mol
H = 1.01 g/mol (12) = 12.12 g/mol
O = 16.00 g/mol (6) = 96.00 g/mol
                                 180.18 g/mol

EtOH C2H5OH

C = 12.01 g/mol (2) = 24.02 g/mol
H =   1.01 g/mol (6) =   6.06 g/mol
O = 16.00 g/mol (1) = 16.00 g/mol
                                    46.08 g/mol

And now we convert g C6H12O6 into g C2H5OH

833 g C6H12O6 
(1 mole C6H12O6) / (180.18 g C6H12O6)
 
(2 moles C2H5OH) / (1 mole C6H12O6)
 
(46.08 g C2H5OH) / (1 mole C2H5OH)
= 426.0699 g C2H5OH


The theoretical yield of EtOH is 426 g