Skip to main content Accessibility help
×
Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-24T03:11:36.595Z Has data issue: false hasContentIssue false

4 - Thermodynamic Potentials

from Part I - Foundations

Published online by Cambridge University Press:  14 December 2018

Jean-Philippe Ansermet
Affiliation:
École Polytechnique Fédérale de Lausanne
Sylvain D. Brechet
Affiliation:
École Polytechnique Fédérale de Lausanne
Get access

Summary

As internal energy is a function of entropy, volume and number of moles, its differential is given by the Gibbs relation, and temperature, pressure and chemical potentials are defined as conjugate variables. Extensivity implies the Euler relation. The Gibbs-Duhem relation will find applications later, in the analysis of phase transitions. Legendre transformations are introduced, leading to the definition of the thermodynamic potentials: free energy, enthalpy and Gibbs free energy. When a system is coupled to a thermal reservoir or heat bath, its equlibrium is characterised by a minimum of the free energy; when it is a work reservoir, the enthalpy is minimum, and when it is a work and heat reservoir, the Gibbs free energy is minimum. Maxwell relations establish relationships between quantities that would not immediately be associated. The cyclic chain rule links together the derivatives of one property function with respect to two others. It is conveniently applied to analyse the Joule expansion and Joule-Thomson effect.

Type
Chapter
Information
Publisher: Cambridge University Press
Print publication year: 2019

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×