1) At 90°C, the vapour pressure of methylbenzene is 53.3 kPa and that of 1,3-dimethylbenzene is 18.0 kPa. What is the composition of a liquid mixture that boils at 90°C when the pressure is 0.40 atm? What is the composition of the vapour produced?
2) The vapour pressure of pure liquid A at 293 K is 68.8 kPa and that of pure liquid B is 82.1 kPa. These two compounds form ideal liquid and gaseous mixtures. Consider the equilibrium composition of a mixture in which the mole fraction of A in the vapour is 0.612. Calculate the total pressure of the vapour and the composition of the liquid mixture.
3) It is found that the boiling point of a binary solution of A and B with xA = 0.479 is 88°C. At this temperature the vapour pressures of pure A and B are 130.1 kPa and 74.9 kPa, respectively. (a) Is this solution ideal? (b) What is the initial composition of the vapour above the solution?