Question: A distillation unit consists of a partial reboiler, a bubble-cap column, and a total condenser. A binary mixture containing 15mol% A and 85 mol% B, which is fed to the optimal plate. Feed is subcooled liquid with quality of 1.10 due to the condensed vapors which are added to the liquid feed. The column is to produce a distillate containing 61 mol% of A and a bottom of 96 mol% B. For an operating pressure of 1 atm, determine the followings by McCabe-Thiele method: i) minimum reflux ratio [5 marks] ii) number of equilibrium stages (N) needed for a reflux ratio of 1.5 times the minimum [6 marks] 111) optimal feed location [1 mark] iv) find N if the Murphree liquid efficiency is assumed to be 50%. [4 marks) NB: for part iv) you must have to show new equilibrium line and new equilibrium stages. Vapor-liquid equilibrium data of A in mole fraction are given as follows: y (mol) x (mol) 0 0 0.22 0.011 0.46 0.084 0.52 0.19 0.57 0.35 0.59 0.45 0.68 0.67 0.74 0.77 0.92 0.94 1 1