Butanol and chlorobenzene form a minimum-boiling azeotropic system. The mole fraction of 1-butanol in the liquid (x) and vapour (y) phases at 1.000 atm is given below for a variety of boiling temperatures Pure chlorobenzene boils at 404.86 K. 

(a) Construct the chlorobenzene-rich portion of the phase diagram from the data. 

(b) Estimate the temperature at which a solution whose mole fraction of 1-butanol is 0.300 begins to boil. 

(c) State the compositions and relative proportions of the two phases present after a solution initially 0.300 1-butanol is heated to 393.94 K.