This problem concerns a mixture of benzene (1) and acetonitrile (2). Antoine equations: log10P1sat=4.01814T53.2261203.835log10P2sat=4.27873T37.8531355.374P1sat,P2sat=[bar]T=[K] Activity coefficient correlations: ln1=x22ln2=x12 a) If the liquid composition of the mixture is 20 mole % benzene and 80 mole\% acetonitrile, what is its bubble point at T=20C ? What is the composition of the vapour in equilibrium with the liquid at this temperature? (10 marks) b) For the conditions in part (a), calculate the partial molar excess Gibbs free energy for each component, and also calculate the excess Gibbs free energy for the mixture. (6 marks) c) What would be the composition of the liquid and the vapour for a mixture at equilibrium that boils at 45C under a pressure of 0.32 bar? ( 8 marks) d) If the vapour-phase composition is 15mole% benzene and 85 mole % acetonitrile, calculate the dew point temperature at a pressure of 0.22 bar. (16 marks)