{"id":4679,"date":"2024-10-03T20:04:20","date_gmt":"2024-10-03T20:04:20","guid":{"rendered":"https:\/\/workhouse.sweetdishy.com\/?p=4679"},"modified":"2024-10-03T20:04:20","modified_gmt":"2024-10-03T20:04:20","slug":"enthalpy-and-free-energies","status":"publish","type":"post","link":"https:\/\/workhouse.sweetdishy.com\/index.php\/2024\/10\/03\/enthalpy-and-free-energies\/","title":{"rendered":"\u00a0Enthalpy and Free Energies"},"content":{"rendered":"\n<p>As interconversion between heat and work is the central concern of thermodynamics, it is useful to define thermodynamic properties that are related to&nbsp;the heat content of a system and energy available for conversion to work. This consideration leads to three thermodynamic functions or properties that are mathematically defined as follows:<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/learning.oreilly.com\/api\/v2\/epubs\/urn:orm:book:9780134594064\/files\/graphics\/08equ03.jpg\" alt=\"Image\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/learning.oreilly.com\/api\/v2\/epubs\/urn:orm:book:9780134594064\/files\/graphics\/08equ04.jpg\" alt=\"Image\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/learning.oreilly.com\/api\/v2\/epubs\/urn:orm:book:9780134594064\/files\/graphics\/08equ05.jpg\" alt=\"Image\"\/><\/figure>\n\n\n\n<p><a><\/a>4. The terms&nbsp;<em>Helmholtz function<\/em>&nbsp;(or Helmholtz energy) and&nbsp;<em>Gibbs function<\/em>&nbsp;(or Gibbs energy) are preferred over classical usage of terms&nbsp;<em>Helmholtz free energy<\/em>&nbsp;and&nbsp;<em>Gibbs free energy<\/em>. Helmholtz function is named after Herrmann Helmholtz, another central founder of the discipline of thermodynamics.<\/p>\n\n\n\n<p>In these equations,&nbsp;<em>P<\/em>,&nbsp;<em>V<\/em>, and&nbsp;<em>T<\/em>&nbsp;are the pressure, volume, and temperature of the system.<\/p>\n\n\n\n<p>Enthalpy of a system is a measure of its heat content, which was discussed in\u00a0Chapter 7, \u201cEnergy Balance Computations.\u201d The significances of the two thermodynamic properties are best understood in terms of changes in the values of\u00a0<em>A<\/em>\u00a0and\u00a0<em>G<\/em>. Simply stated, the change in Helmholtz energy represents the maximum amount of work that can be obtained from the system, whereas the change in Gibbs energy represents the maximum amount of work that can be extracted from the system\u00a0<em>excluding any work of expansion<\/em>. Mathematically [6], this is as follows:<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/learning.oreilly.com\/api\/v2\/epubs\/urn:orm:book:9780134594064\/files\/graphics\/08equ06.jpg\" alt=\"Image\"\/><\/figure>\n\n\n\n<figure class=\"wp-block-image\"><img decoding=\"async\" src=\"https:\/\/learning.oreilly.com\/api\/v2\/epubs\/urn:orm:book:9780134594064\/files\/graphics\/08equ07.jpg\" alt=\"Image\"\/><\/figure>\n\n\n\n<p>Here,\u00a0<em>W<sub>max<\/sub><\/em>\u00a0represents the maximum work that can be extracted from the system.\u00a0Equations 8.6\u00a0and\u00a08.7\u00a0indicate that any work extracted from the system (done by the system) is at the expense of the Helmholtz energy and Gibbs energy, respectively. Gibbs energy is also the key thermodynamic property in determination of system equilibrium, as will be discussed later.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>As interconversion between heat and work is the central concern of thermodynamics, it is useful to define thermodynamic properties that are related to&nbsp;the heat content of a system and energy available for conversion to work. This consideration leads to three thermodynamic functions or properties that are mathematically defined as follows: 4. The terms&nbsp;Helmholtz function&nbsp;(or Helmholtz [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":4602,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[564],"tags":[],"class_list":["post-4679","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-computations-in-chemical-engineering-thermodynamics"],"jetpack_featured_media_url":"https:\/\/workhouse.sweetdishy.com\/wp-content\/uploads\/2024\/09\/thermodynamics.png","_links":{"self":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts\/4679","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/comments?post=4679"}],"version-history":[{"count":1,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts\/4679\/revisions"}],"predecessor-version":[{"id":4680,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/posts\/4679\/revisions\/4680"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/media\/4602"}],"wp:attachment":[{"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/media?parent=4679"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/categories?post=4679"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/workhouse.sweetdishy.com\/index.php\/wp-json\/wp\/v2\/tags?post=4679"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}