Answer:
0.116
Explanation:
The molar mass of ethanol is 46.07 g/mol. The moles corresponding to 25.0 g are:
25.0 g × (1 mol/46.07 g) = 0.543 mol
The molar mass of water is 18.02 g/mol. The moles corresponding to 75.0 g are:
75.0 g × (1 mol/18.02 g) = 4.16 mol
The total number of moles is:
total moles = mol ethanol + mol water = 0.543 mol + 4. 16 mol = 4.70 mol
The mole fraction of ethanol is:
X(Ethanol) = mol ethanol / total moles = 0.543 mol / 4.70 mol = 0.116
