A solution of ethanol, CH3CH2OH, in water has a concentration of 1.25 molality. Calculate the mass percent of ethanol in the solution.

A solution of ethanol, CH3CH2OH, in water has a concentration of 1.25 molality. Calculate the mass percent of ethanol in the solution. 




1,25*46=57,5 g of EtOH in
1000 g of H2O. We have 1057,5 g
of sol.,that consist 57,5 g of EtOH.
%m(EtOH)=57,5:1057,5*100=5,44 %