Question 3 (18 points) A feed of saturated liquid mixture of n-hexane-n-Decan containing 40 mole% n-hexane is to be separated into a distillate containing 95 mole% hexane and a bottoms containing 10 mole% hexane. The operation is to be carried out in column with a reboiler and total condenser. Reflux is saturated liquid. Using the Ponchon-Savarit approach and enthalpy concentration diagrams that are provided below: a. What is the minimum number of stages the column must have to carry out the separation? (3 points) 26000 24000 22000 20000 18000 16000 14000 12000 Enthalpy kcal/kmol 10000 8000 0.9 6000 0.8 0.7 4000 0.6 0.5 2000 0.4 0.3 O 0.2 0.1 -2000 y.x hexane -4000 -6000