Question

Calculate the mass fraction and mole fraction of ethyl alcohol and water containing 9.2g alcohol and 18g water

Answer 1

Calculate the mass fraction and mole fraction of ethyl alcohol and water in a solution containing 9.2g of alcohol in 18.0g of water .

Answer 2

Answer:Mole fraction of water and alcohol is 0.83 and 0.16 respectively.

Mass fraction of water and alcohol is 66.17% and 33.83 % respectively.

Explanation:

Moles of water = $n_w=\frac{18 g}{18 g/mol}=1 mol$

Moles of alcohol = $n_a=\frac{9.2 g}{46 g}=0.2 mol$

Mole fraction of water =$\chi _w=\frac{n_w}{n_w+n_a}=\frac{1}{1.2}=0.83$

Mass fraction of water :$\frac{18 g}{27.2 g}\times 100 =66.17\%$

Mole fraction of alcohol = $\chi _a=1-\chi_w=1-0.83=0.16$

Mass fraction of alcohol = $\frac{9.2 g}{27.2 g}\times 100 =33.83\%$