A mixture of benzene and toluene is in a tank whose pressure is maintained at 2.0 atm. Observation through a sight glass on the vessel shows that half of the tank volume is occupied by liquid. Analysis shows that the liquid contains 50.0 wt% benzene and the balance toluene. Raoult’s law applies at all compositions, and the density of the liquid is essentially independent of temperature. Estimate (a) the temperature and (b) the fraction of the system mass in the liquid phase.