Question

The mole fraction of solvent in 0.1  molal aqueous solution is

Answer 1

0.1 molal aqueous solution means 0.1 moles in 1000 gram water
moles of water =55.5 moles
mole fraction= 0.1/(0.1+55.5)
0.00179

Answer 2

Answer: The mole fraction of solvent in 0.1  molal aqueous solution is 0.9982.

Explanation:

1 molal aqueous solution means that 1 mol/kg that is 1 mol of solute is present in the 1000 g of the water(here the aqueous means that solvent is water).

Moles of solvent =$\frac{\text{mass of the water}}{\text{Molar mass of the water}}=\frac{1000 g}{18 g/mol}=55.55 mol$

Moles of solute =  0.1 mol (given)

$\chi_{solvent}=\frac{\text{moles od solvent}}{\text{Moles of solvent+Moles of Solute}}=\frac{55.55}{55.55+0.1}=0.9982$

The mole fraction of solvent in 0.1  molal aqueous solution is 0.9982.