{"id":249782,"date":"2025-07-09T21:12:32","date_gmt":"2025-07-09T21:12:32","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=249782"},"modified":"2025-07-09T21:12:34","modified_gmt":"2025-07-09T21:12:34","slug":"i-thought-about-using-kpkcrtdelta-n-but-im-not-sure-what-to-do-with-the-two-given-kc-values","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/09\/i-thought-about-using-kpkcrtdelta-n-but-im-not-sure-what-to-do-with-the-two-given-kc-values\/","title":{"rendered":"I thought about using Kp=Kc(RT)^(delta n) but I&#8217;m not sure what to do with the two given Kc values."},"content":{"rendered":"\n<p>I thought about using Kp=Kc(RT)^(delta n) but I&#8217;m not sure what to do with the two given Kc values.<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p>When you&#8217;re given two values for the equilibrium constant KcK_cKc\u200b and you want to relate them using the equation Kp=Kc(RT)\u0394nK_p = K_c (RT)^{\\Delta n}Kp\u200b=Kc\u200b(RT)\u0394n, it&#8217;s important to first understand the components of the equation.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>KpK_pKp\u200b: The equilibrium constant in terms of partial pressures.<\/li>\n\n\n\n<li>KcK_cKc\u200b: The equilibrium constant in terms of concentrations.<\/li>\n\n\n\n<li>RRR: The ideal gas constant, which is usually 0.0821\u2009L\\cdotpatm\/mol\\cdotpK0.0821 \\, \\text{L\u00b7atm\/mol\u00b7K}0.0821L\\cdotpatm\/mol\\cdotpK if you&#8217;re using pressure in atmospheres and volume in liters.<\/li>\n\n\n\n<li>TTT: Temperature in Kelvin.<\/li>\n\n\n\n<li>\u0394n\\Delta n\u0394n: The change in the number of moles of gas from reactants to products. This is calculated by subtracting the moles of gaseous reactants from the moles of gaseous products.<\/li>\n<\/ul>\n\n\n\n<p>If you&#8217;re given two KcK_cKc\u200b values at different temperatures, you can use the Van\u2019t Hoff equation to find the relationship between the constants: ln\u2061(Kc2Kc1)=\u2212\u0394H\u2218R(1T2\u22121T1)\\ln \\left( \\frac{K_{c2}}{K_{c1}} \\right) = &#8211; \\frac{\\Delta H^\\circ}{R} \\left( \\frac{1}{T_2} &#8211; \\frac{1}{T_1} \\right)ln(Kc1\u200bKc2\u200b\u200b)=\u2212R\u0394H\u2218\u200b(T2\u200b1\u200b\u2212T1\u200b1\u200b)<\/p>\n\n\n\n<p>Where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Kc1K_{c1}Kc1\u200b and Kc2K_{c2}Kc2\u200b are the equilibrium constants at temperatures T1T_1T1\u200b and T2T_2T2\u200b.<\/li>\n\n\n\n<li>\u0394H\u2218\\Delta H^\\circ\u0394H\u2218 is the standard enthalpy change for the reaction.<\/li>\n<\/ul>\n\n\n\n<p>In this case, the first step is to identify the relationship between the two KcK_cKc\u200b values. You can calculate \u0394n\\Delta n\u0394n from the balanced chemical equation, then use Kp=Kc(RT)\u0394nK_p = K_c (RT)^{\\Delta n}Kp\u200b=Kc\u200b(RT)\u0394n to convert between the concentration-based equilibrium constant and the pressure-based equilibrium constant if the equation involves gases. If the temperatures are different, and you&#8217;re only given the two KcK_cKc\u200b values, using the Van&#8217;t Hoff equation can help you connect them.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/07\/learnexams-banner6-54.jpeg\" alt=\"\" class=\"wp-image-249783\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>I thought about using Kp=Kc(RT)^(delta n) but I&#8217;m not sure what to do with the two given Kc values. The Correct Answer and Explanation is: When you&#8217;re given two values for the equilibrium constant KcK_cKc\u200b and you want to relate them using the equation Kp=Kc(RT)\u0394nK_p = K_c (RT)^{\\Delta n}Kp\u200b=Kc\u200b(RT)\u0394n, it&#8217;s important to first understand the [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-249782","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/249782","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=249782"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/249782\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=249782"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=249782"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=249782"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}