A solution is made using 23.3 percent by mass
CH_(2)Cl_(2)in
CHCl_(3). At
30\deg C, the vapor pressure of pure
CH_(2)Cl_(2)is 490 mm Hg , and the vapor pressure of pure
CHCl_(3)is 260 mm Hg . The normal boiling point of
CHCl_(3)is 61.7
\deg C. What is the molality of
CH_(2)Cl_(2)in the solution?