Question

138g of ethyl alcohol is mixed with 72 g of water. the ratio of mole fraction

Answer 1

$n(eth \: alc) = \frac{138}{46} = 3moles \\ n(water) = \frac{72}{18} = 4moles$
$x(eth \: alc) = \frac{3}{7} \\ x(water) = \frac{4}{7}$