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# A 5.0 molal aqueous solution of methyl alcohol,$CH_3OH$ is supplied.What is the mole fraction of methyl alcohol in the solution?

$\begin{array}{1 1}(a)\;1.100\\(b)\;0.190\\(c)\;0.082\\(d)\;0.050\end{array}$

A 5.0 molal aqueous solution of methyl alcohol,CH3OH is supplied.What is the mole fraction of methyl alcohol in the solution?
Mole fraction $\large\frac{\text{moles of solute}}{\text{total moles in solution}}$
Number of moles of Methyl Alcohol $= 5.0\; mols$
This is in $1000\;g$ of water, so number of moles of water $= \large\frac{1000}{18} $$= 55.55, where molar mass of water = 18.01528\; g\;mol^{-1} \Rightarrow Mole Fraction = \large\frac{5.0}{5.0+55.55}$$ =0.082$
edited Jul 16, 2014