(a) If the vapor pressure of a solution A and B is P

b) Give graphically the lowering of the freezing point and the raising of the boiling point of a dilute solution of a non-volatile substance based on the diagram of the chemical potential with respect to temperature. Justify your answer. (0.5).

c) The vapor pressures of benzene and water at various temperatures

are given in the table below,

Temperature c. 20 40 60 80

P* H20 (atm). 0.02 0.0725 0.196 0.467

P* C6H6 0.098 0.238 0.512 0.992

At what temperatures, under a pressure of 0.5 and 1 atm, will a mixture of these two liquids, which are said to be immiscible, begin to evaporate? (2).

Please answer the whole problem.