An enthalpy-concentration diagram is given in Figure for a mixture of n-hcxanc (H). and n-octane (0) at 101 kPa. Using this diagram, determine the following:

(a) The mole-fraction composition of the vapor when a liquid containing 30 mol% H is heated from point A to the bubble-point temperature at point B.

(b) The energy required to vaporize 60 mol% of a mixture initially at l00oF and containing 20 mol% H (point G).

(c) The compositions of the equilibrium vapor and liquid resulting from part(b).

300 F 280 F 260 F 30 Saturated vapor 20 Saturated liquid 10 140 F 120 F 100 F G A P = 1 atm 1.0 0.8 0.6 0.4 0.2 Mole fraction of n-hexane, x or y Figure 7.37 Enthalpy-concentration diagram for n-hexane/ n-octane. Enthalpy, Btu/lbmol x 10-3 240 F 220 F B. 200 F do 081 do 091