Ans: Theoretical yield = 365.8 g
% yield = 89.3%
Given reaction:
C12H22O11 + H2O → 4C2H5OH + 4CO2
Mass of sucrose = 680 g
Molar mass of sucrose = 342 g/mol
# moles of sucrose = 680/342 = 1.988 moles
Based on stoichiometry:
1 mole of sucrose forms 4 moles of ethanol
1.988 moles of sucrose will yield: 1.988*4 = 7.952 moles of ethanol
Molar mass of ethanol = 46 g/mol
Theoretical yield of ethanol = 7.952*46 = 365.8 g
% yield = (experimental/theoretical )*100 = (326.5/365.8)*100 = 89.3%