[azhagan]

An ideal solution of 5.00 mol of benzene and 3.25 mol of toluene is placed in a piston and cylinder  assembly. At 298 K, the vapor pressure of the pure substances of p*benzene=96.4 Torr and p*toluene = 28.9 Torr.
a. The pressure above this solution is reduced from 760.0 Torr. At what pressure does the vapor phase first appear?
b. What is the composition of the vapor under these conditions?
c. The total pressure in the vapor is 66.8 Torr when 1.50 mol of the solution has been converted to vapor.  Use this information to calculate the liquid composition and the vapor composition when 1.50 mol of the solution has been converted to vapor.

[Borek]

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