A solution contains 4 kmol of benzene and 6 kmol of toluene at 15 kPa and 20°C. Now the pressure is slowly reduced to 3 kPa. Using the data of Problem 17.21 a. Find the pressure at which the fi rst...

A solution contains 4 kmol of benzene and 6 kmol of toluene at 15 kPa and 20°C. Now the pressure is slowly reduced to 3 kPa. Using the data of Problem 17.21

a. Find the pressure at which the fi rst bubble of vapor appears.

 b. Find the mole fraction of benzene in the fi rst bubble.

 c. Find the pressure at which the last drop evaporates.

Problem 17.21~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Benzene and toluene form at 20°C an ideal solution for all concentrations. For benzene

a. Find the saturation pressure (liquid line) as a function of benzene mole fraction.

 b. Find the corresponding vapor line in equilibrium with the liquid.

 c. Draw a pressure–concentration diagram with the vapor and liquid lines.