The following temperature-composition data were obtained for a mixture of octane (0) and toluene (T) at 760 Torr, where x is the mole fraction in the liquid and ythe mole fraction in the vapour at...

The following temperature-composition data were obtained for a mixture of octane (0) and toluene (T) at 760 Torr, where
x
is the mole fraction in the liquid and ythe mole fraction in the vapour at equilibrium .

θ/°C    110.9    112.0    114.0    115.8    117.3    119.0    120.0    123.0

X_r

 0.908    0.795     0.615    0.527   0.408     0.300    0.203    0.097

Y_T

0.923    0.836     0.698   0.624    0.527     0.410    0.297    0.164
The boiling points are 110.6 °C for toluene and 125.6 °C for octane. Plot the temperatur-composition diagram of the mixture . What is the composition of the vapour in equilibrium with the liquid of composition (a)
X_T

= 0.250 and (b)
x_O

= 0.250?