{"id":206626,"date":"2025-06-16T08:48:04","date_gmt":"2025-06-16T08:48:04","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=206626"},"modified":"2025-06-16T08:48:06","modified_gmt":"2025-06-16T08:48:06","slug":"determine-the-direction-that-each-of-the-reactions-will-progress","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/16\/determine-the-direction-that-each-of-the-reactions-will-progress\/","title":{"rendered":"Determine the direction that each of the reactions will progress"},"content":{"rendered":"\n

Determine the direction that each of the reactions will progress. Assume that the reactants and products are present in equimolar amounts. The standard free energy of hydrolysis of ATP is – 30.5 kJ\/mol. fructose + ATP fructose 6-phosphate + ADP The standard free energy of hydrolysis for fructose 6-phosphate is -15.9 kJ\/mol. 3-phosphoglycerate + ATP 1,3-bisphosphoglycerate + ADP The standard free energy of hydrolysis for 1,3-bisphosphoglycerate is -49.3 kJ\/mol. creatine + ATP creatine phosphate + ADP The standard free energy of hydrolysis for creatine phosphate is -43.0 kJ\/mol.<\/p>\n\n\n\n

The correct answer and explanation is:<\/mark><\/strong><\/p>\n\n\n\n

To determine the direction of each reaction, we compare the net standard free energy change (\u0394G\u00b0’)<\/strong> of the reaction. If \u0394G\u00b0’ is negative<\/strong>, the reaction proceeds forward<\/strong>; if positive<\/strong>, it proceeds in reverse<\/strong>. Since reactants and products are present in equimolar amounts<\/strong>, we use standard free energy values<\/strong> directly.<\/p>\n\n\n\n

\n\n\n\n

Reaction 1:<\/strong><\/h3>\n\n\n\n

fructose + ATP \u2192 fructose 6-phosphate + ADP<\/strong><\/p>\n\n\n\n

    \n
  • \u0394G\u00b0’ for ATP hydrolysis = \u201330.5 kJ\/mol<\/strong><\/li>\n\n\n\n
  • \u0394G\u00b0’ for fructose 6-phosphate hydrolysis = \u201315.9 kJ\/mol<\/strong><\/li>\n<\/ul>\n\n\n\n

    So, the reverse of this reaction would be:
    fructose 6-phosphate + ADP \u2192 fructose + ATP<\/strong>
    \u0394G\u00b0’ = (\u201315.9) \u2013 (\u201330.5) = +14.6 kJ\/mol<\/strong><\/p>\n\n\n\n

    That means the forward reaction (fructose + ATP \u2192 fructose 6-phosphate + ADP)<\/strong> has
    \u0394G\u00b0’ = \u201314.6 kJ\/mol<\/strong>, so it proceeds forward<\/strong>.<\/p>\n\n\n\n

    \n\n\n\n

    Reaction 2:<\/strong><\/h3>\n\n\n\n

    3-phosphoglycerate + ATP \u2192 1,3-bisphosphoglycerate + ADP<\/strong><\/p>\n\n\n\n

      \n
    • \u0394G\u00b0’ for ATP hydrolysis = \u201330.5 kJ\/mol<\/li>\n\n\n\n
    • \u0394G\u00b0’ for 1,3-bisphosphoglycerate hydrolysis = \u201349.3 kJ\/mol<\/li>\n<\/ul>\n\n\n\n

      Reverse reaction:
      1,3-bisphosphoglycerate + ADP \u2192 3-phosphoglycerate + ATP<\/strong>
      \u0394G\u00b0’ = (\u201349.3) \u2013 (\u201330.5) = \u201318.8 kJ\/mol<\/strong><\/p>\n\n\n\n

      Thus, the forward reaction has \u0394G\u00b0’ = +18.8 kJ\/mol<\/strong>, so it proceeds in reverse<\/strong>.<\/p>\n\n\n\n

      \n\n\n\n

      Reaction 3:<\/strong><\/h3>\n\n\n\n

      creatine + ATP \u2192 creatine phosphate + ADP<\/strong><\/p>\n\n\n\n

        \n
      • \u0394G\u00b0’ for ATP hydrolysis = \u201330.5 kJ\/mol<\/li>\n\n\n\n
      • \u0394G\u00b0’ for creatine phosphate hydrolysis = \u201343.0 kJ\/mol<\/li>\n<\/ul>\n\n\n\n

        Reverse:
        creatine phosphate + ADP \u2192 creatine + ATP<\/strong>
        \u0394G\u00b0’ = (\u201343.0) \u2013 (\u201330.5) = \u201312.5 kJ\/mol<\/strong><\/p>\n\n\n\n

        So, forward reaction has \u0394G\u00b0’ = +12.5 kJ\/mol<\/strong>, hence the reaction proceeds in reverse<\/strong>.<\/p>\n\n\n\n

        \n\n\n\n

        \u2705 Summary<\/strong>:<\/h3>\n\n\n\n
        Reaction<\/th>Direction<\/th><\/tr><\/thead>
        Fructose + ATP \u2192 fructose 6-phosphate + ADP<\/td>Forward<\/strong><\/td><\/tr>
        3-phosphoglycerate + ATP \u2192 1,3-bisphosphoglycerate + ADP<\/td>Reverse<\/strong><\/td><\/tr>
        Creatine + ATP \u2192 creatine phosphate + ADP<\/td>Reverse<\/strong><\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

        Explanation<\/strong><\/h3>\n\n\n\n

        The direction a biochemical reaction proceeds depends largely on its standard Gibbs free energy change (\u0394G\u00b0’). If \u0394G\u00b0’ is negative, the reaction is thermodynamically favorable and will proceed forward. If positive, the reverse reaction is favored.<\/p>\n\n\n\n

        ATP hydrolysis releases a significant amount of energy (\u201330.5 kJ\/mol), making it a common driving force in coupled biochemical reactions. To evaluate the direction of each reaction, we analyze the free energy change of the overall process<\/strong> by comparing the \u0394G\u00b0’ of ATP hydrolysis with that of the product being formed.<\/p>\n\n\n\n

        In the first reaction, fructose is phosphorylated to fructose 6-phosphate using ATP. The hydrolysis of fructose 6-phosphate is less exergonic (\u201315.9 kJ\/mol) than ATP, so the overall \u0394G\u00b0’ is negative, making the forward reaction spontaneous.<\/p>\n\n\n\n

        In the second and third reactions, ATP is used to form high-energy compounds\u20141,3-bisphosphoglycerate and creatine phosphate. However, both of these compounds release more energy upon hydrolysis (\u201349.3 and \u201343.0 kJ\/mol respectively) than ATP. Therefore, synthesizing them from ATP is unfavorable<\/strong>, meaning the reverse reactions are favored<\/strong> thermodynamically.<\/p>\n\n\n\n

        This analysis is crucial in metabolism, where ATP is used to drive otherwise unfavorable reactions by coupling them with its highly exergonic hydrolysis.<\/p>\n\n\n\n

        \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

        Determine the direction that each of the reactions will progress. Assume that the reactants and products are present in equimolar amounts. The standard free energy of hydrolysis of ATP is – 30.5 kJ\/mol. fructose + ATP fructose 6-phosphate + ADP The standard free energy of hydrolysis for fructose 6-phosphate is -15.9 kJ\/mol. 3-phosphoglycerate + ATP […]<\/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-206626","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206626","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=206626"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/206626\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=206626"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=206626"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=206626"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}