3. (15 points) Figure 2 shows a P-x diagram for the binary system of ethane and n-pentane at 300 K. a. (3 points) Is the critical temperature of pure ethane lower than 300K ? Explain why, or why not. b. (5 points) 12 gram of ethane is initially in a PVT cell at 300K and 1500kPa. Then, a certain amount of n-pentane is added to reach a bubble point at this temperature-pressure condition. How many grams of n-pentane should be injected into the PVT cell? The molecular weight of ethane and n-pentane are given in Table 6.6-1 of Sandler (attached). The ethane concentration in the equilibrium liquid phase is 43mol%, and that in the equilibrium vapor phase is 95mol%, at 300K and 1500kPa. c. (5 points) An additional amount of A-pentane ethane is added to the mixture so that the overall ethane concentration in the mixture is 60 mol\%. Then, two phases (vapor and liquid) form at equilibrium at 300K and 1500kPa. What is the mole fraction of the vapor phase? d. (2 points) The diagram shows a few tie lines. Are these tie lines horizontal in this diagram? Why or why not? Discuss equilibrium conditions