It is necessary to separate by distillation 100 kmol/h of a process stream containing 60 mol% benzene and 40 mol % ethylbenzene, with the objective of obtaining a high purity (99.5 mol %) benzene product and an ethylbenzene product. Two schemes are to be considered: Scheme I: An initial flash separation prior to distillation, and then distil the resulting benzene- rich product to remove the ethylbenzene. This process is shown schematically in Figure 1 below. The feed to the flash separator is at its boiling point, with 60% vapour. The vapour stream is then fed to a distillation column having a reflux ratio of 1. Scheme II: A direct distillation of the process stream (at its boiling point); reflux ratio of 1. Determine: a) The concentration of the vapor and liquid streams from the flash operation; b) The number of stages necessary to produce a bottoms product of 99% ethylbenzene for scheme I. c) The number of stages for the distillation column of scheme II to produce the two products of the same composition as in scheme I Equilibrium X-Y plots are included for your use.