For the binary system 2, 4-dimethylpentane (1) + benzene (2) the excess Gibbs energy of the liquid phase is given by:
G^{E}/(x_{1}x_{2}) = (A_{12}x_{1} + A_{21}x_{2})
a. Calculate the constants A_{12} and A_{21} if γ*_{1} = 1.958 and γ*_{2} = 1.478
b. Calculate at 60^{°}C the pressure and composition of the vapor phase which is in equilibrium with a liquid phase with composition x_{1} = 0.5. At this temperature the saturated vapor pressures of component 1 and 2 are respectively 52.4 and 52.3 kPa. The vapor phase is ideal and the Poynting correction can be ignored.
c. Calculate Henry's constant of component 2 in pure component 1 and of component 1 in pure component 2.