Trichloroethane, C2H3Cl3, is the active ingredient in aerosols that claim to stain-proof...

Trichloroethane, C₂H₃Cl₃, is the active ingredient in aerosols that claim to stain-proof men’s ties. Trichloroethane has a vapor pressure of 100.0 mm Hg at 20.0°C and boils at 74.1°C. An uncovered cup of trichloroethane (d = 1.325 g/mL) is kept in an 18-ft³ refrigerator at 39°F. What percentage (by mass) of the trichloroethane is left as a liquid when equilibrium is established?