A mixture of 4.00 gram-moles of benzene and 6.00 gram-moles of toluene are placed in a closed cylinder equipped with a piston. The cylinder is immersed in a bath of boiling water that maintains the temperature at 100.0C. The force exerted on the piston can be varied to adjust the cylinder pressure to any desired values. The pressure is initially 1300 mm Hg and is gradually lowered to 600 mm Hg. Use the Pxy diagram below to convince yourself that the cylinder initially contains only liquid benzene and toluene and to answer the following questions. 115 110 105 100 95 Vapor 1400 1300 1200 1100 Temperature (C) 90 Liquid 1000 Pressure (mm Hg) Liquid 85 900 80 800 Vapor 75 700 70 65 0 600 500 0 1.0 1.0 0.2 0.4 0.6 0.8 Mole fraction benzene P= 1 atm 0.2 0.4 0.6 0.8 Mole fraction benzene T = 100C (a) Txy diagram (b) Pxy diagram Bubble Point X Carefully read the diagram. The solution can be sensitive to small errors. At what pressure does the first vapor bubble form? i 500 mm Hg What is its composition? i 0 mol benzene/mol At what pressure does the last droplet of liquid evaporate? i mm Hg What is its composition? mol benzene/mol Save for Later Attempts: 0 of 3 used Submit Answer Phase Ratio What are the liquid and vapor compositions in equilibrium with each other when the pressure is 800 mm Hg? Vapor: i mol benzene/mol Liquid: i mol benzene/mol What is the ratio (mole vapor/mole liquid) at this point? i Estimate the volume of the cylinder contents when the pressure is 1300 mm Hg, 800 mm of Hg, and 600 mm Hg. 1300 mm Hg: i L 800mm of Hg: i L 600 mm Hg: i L