Refer to the information in Exercise 5C.8(a) and sketch the cooling curves for liquid mixtures in which x(CF4) is (i) 0.10, (ii) 0.30, (iii) 0.50, (iv) 0.80, and (v) 0.95.

Data in Exercise 5C.8(a)

Methane (melting point 91K) and tetrafluoromethane (melting point 89K) do not form solid solutions with each other, and as liquids they are only partially miscible. The upper critical temperature of the liquid mixture is 94K at x(CF₄)=0.43 and the eutectic temperature is 84K at x(CF₄)=0.88. At 86K, the phase in equilibrium with the tetrafluoromethane-rich solution changes from solid methane to a methane-rich liquid. At that temperature, the two liquid solutions that are in mutual equilibrium have the compositions x(CF₄)=0.10 and x(CF₄)=0.80. Sketch the phase diagram.