Question

the mole percentage of 46%(w/w) ethyl alcohol aqueous solution is

Answer 1

hi there.....!!

mole fraction = mole of one of the component of the solution
                                                  total moles of the solution

Calculating the mole fraction of ethanol for the question above: 

Note: we will use a 100 g sample of this solution for the calculation.

Percentage by weight of ethyl alcohol is 46%...that means in 100 g of this solution is 46 g while the mass of the water will be 54% of 100 g = 54g.

Find the moles of water and the ethyl alcohol {molar mass of water(H₂O) = 18 and molar mass of ethyl alcohol(C₂H₆O = 46}

Moles = mass/molar mass

moles of ethanol = 46/46 = 1

moles of water = 54/18 = 3

total moles = 1 + 3 = 4

Mole fraction of ethanol is: 

                     Mole of ethanol            =   1/4
                   Total mole of solution

Therefore the mole fraction is 1/4 or 0.25

hope this helps you......!!!