posted by rita .
A solution prepared by dissolving 20.2 mL of CH3OH in 100mL of water @ 25 celcius. The final volume of the solution is 118 mL. Calculate the % by mass.
density CH3OH[0.782g/mL], H20[1g/mL] @ room temp.
%w/w = mass solute/100 g soln
mass solute = 20.2 mL x 0.782 g/mL = ?
mass soln = 100 g(H2O) + ?g solute = xx
%by mass = (?g solute/xxg soln)*100 =z%