Concept# Duhem–Margules equation

Summary

The Duhem–Margules equation, named for Pierre Duhem and Max Margules, is a thermodynamic statement of the relationship between the two components of a single liquid where the vapour mixture is regarded as an ideal gas:
: \left ( \frac{\mathrm{d}\ln P_A}{\mathrm{d}\ln x_A} \right )*{T,P} = \left ( \frac{\mathrm{d}\ln P_B}{\mathrm{d}\ln x_B} \right )*{T,P}
where PA and PB are the partial vapour pressures of the two constituents and xA and xB are the mole fractions of the liquid. The equation gives the relation between changes in mole fraction and partial pressure of the components.
Derivation
Let us consider a binary liquid mixture of two component in equilibrium with their vapor at constant temperature and pressure. Then from the Gibbs–Duhem equation, we have
Where nA and nB are number of moles of the component A and B while μA and μB are their chemical potentials.
Dividing equation () by nA + nB, then
: \frac{n_A}{n_A+n_B} \mathrm{d}\mu_A + \fr

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related publications

Loading

Related people

Loading

Related units

Loading

Related concepts

Loading

Related courses

Loading

Related lectures

Loading

Related publications

No results

Related people

No results

Related units

Related lectures

No results

No results

Related concepts

Related courses

No results

No results