Question

given a 100 proof alcohol solution (C2H5OH in H20) with a mole fraction of 0.235. what is the wt% of C2H5OH

Answer 1

Solution :-

mole fraction of the enthanol = 0.235

threfore mole fraction water = 1 - 0.235 = 0.765

lets calculate the mass of the each

mass of ethanol = moles * molar mass

                         = 0.235 * 46.068 g per mol

                         = 10.83 g

mass of water = 0.765 mol * 18.0148 g per mol = 13.78 g

now total mass of solution = 10.83 g + 13.78 g = 24.61 g

lets calculate the wt percent of the ethanol

% w = (mass of ethanol / total mass )*100%

      = (10.83 g / 24.61 g)*100%

      = 44.01 %