Enthalpy-Concentration Plot for a Benzene-Toluene Binary Mixture

This Demonstration displays the enthalpy-concentration plot for values of the specified total pressure (expressed in mmHg). The ideal binary mixture considered is composed of benzene and toluene. The saturated vapor and liquid enthalpies, and (expressed in kJ/kg·mole), are represented by the dark blue and red curves, respectively, where the vapor and liquid mole fractions of benzene are designated by and , respectively. The reference temperature, used in the calculation of and , is such that the liquid enthalpy of pure benzene at the boiling point is equal to zero. The tie lines are displayed in green for an equal spacing of the liquid mole fraction of benzene. This Demonstration also shows how any tie line is constructed if the conjugate curve (displayed in light blue) is available. Here, the liquid and vapor enthalpies can be approximated by two parallel lines (i.e., the molar latent heats of chemically similar compounds, benzene and toluene, are almost the same). This has implications in the distillation of the binary benzene-toluene mixture. Indeed, one can safely make the constant molal overflow or CMO assumption, which will result in straight operating lines in the McCabe & Thiele graphical construction.


  • [Snapshot]
  • [Snapshot]
  • [Snapshot]


C. J. Geankoplis, Transport Processes and Unit Operations, 3rd ed., Englewood Cliffs: Prentice Hall International Editions, 1993.
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.

Mathematica »
The #1 tool for creating Demonstrations
and anything technical.
Wolfram|Alpha »
Explore anything with the first
computational knowledge engine.
MathWorld »
The web's most extensive
mathematics resource.
Course Assistant Apps »
An app for every course—
right in the palm of your hand.
Wolfram Blog »
Read our views on math,
science, and technology.
Computable Document Format »
The format that makes Demonstrations
(and any information) easy to share and
interact with.
STEM Initiative »
Programs & resources for
educators, schools & students.
Computerbasedmath.org »
Join the initiative for modernizing
math education.
Step-by-Step Solutions »
Walk through homework problems one step at a time, with hints to help along the way.
Wolfram Problem Generator »
Unlimited random practice problems and answers with built-in step-by-step solutions. Practice online or make a printable study sheet.
Wolfram Language »
Knowledge-based programming for everyone.
Powered by Wolfram Mathematica © 2018 Wolfram Demonstrations Project & Contributors  |  Terms of Use  |  Privacy Policy  |  RSS Give us your feedback
Note: To run this Demonstration you need Mathematica 7+ or the free Mathematica Player 7EX
Download or upgrade to Mathematica Player 7EX
I already have Mathematica Player or Mathematica 7+