{"id":10712,"date":"2026-09-26T13:54:30","date_gmt":"2026-09-26T12:54:30","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/catalysts-and-reaction-profiles\/"},"modified":"2026-10-04T23:03:17","modified_gmt":"2026-10-04T22:03:17","slug":"catalysts-and-reaction-profiles","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/catalysts-and-reaction-profiles\/","title":{"rendered":"Catalysts and Reaction Profiles"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-kinetics-equilibria-page\">\n  <style>\n    .ols-revision-page {\n      --navy: #1C244B;\n      --blue: #2563eb;\n      --soft-blue: #eef4ff;\n      --soft-red: #fff7f7;\n      --soft-purple: #f7f0ff;\n      --soft-green: #f0f7f1;\n      --gold: #c9973a;\n      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20px;\n      box-shadow: var(--inner-shadow);\n    }\n.ols-faq-item h3 {\n      margin: 0 0 8px;\n      font-size: 20px;\n      line-height: 1.3;\n      color: var(--navy);\n    }\n.ols-faq-item p {\n      margin: 0;\n      font-size: 16px;\n      line-height: 1.65;\n      color: var(--body-text);\n    }\n.ols-faq-card,\n      .ols-quicksnap-card,\n      .ols-attribution-card {\n        padding: 24px 18px;\n        border-radius: 22px;\n      }\n  <\/style>\n\n    <aside class=\"ols-sidebar\">\n  <div class=\"ols-sidebar-header\">\n    <h3>Revision Notes<\/h3>\n    <p>A Level Chemistry<\/p>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Topic 9 Kinetics &amp; Equilibria<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/\">Topic 9 Overview<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/\">Topic 9A Kinetics<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/collision-theory-and-rates-of-reaction\/\">Collision Theory and Rates of Reaction<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/measuring-and-calculating-rates\/\">Measuring and Calculating Rates<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/maxwell-boltzmann-distribution\/\">The Maxwell\u2013Boltzmann Distribution<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/catalysts-and-reaction-profiles\/\">Catalysts and Reaction Profiles<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/core-practicals\/cp-9a-9b-iodine-propanone-and-clock-reaction-kinetics\/\">Core Practical 9A\/9B<\/a>\n          <\/li>\n        <\/ul>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9b-equilibria\/\">Topic 9B Equilibria<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9b-equilibria\/dynamic-equilibrium\/\">Dynamic Equilibrium<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9b-equilibria\/le-chateliers-principle\/\">Le Chatelier's Principle<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9b-equilibria\/equilibria-in-industry\/\">Equilibria in Industry<\/a>\n          <\/li>\n        <\/ul>\n      <\/li>\n    <\/ul>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Other Topics<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/\">Topic 6 Energetics<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-7-intermolecular-forces\/\">Topic 7 Intermolecular Forces<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-8-redox-chemistry-and-groups-1-2-and-7\/\">Topic 8 Redox &amp; Groups 1, 2 and 7<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/core-practicals\/\">Core Practicals<\/a>\n      <\/li>\n    <\/ul>\n  <\/div>\n<\/aside>\n\n<script>\r\n(function() {\r\n  function normalisePath(path) {\r\n    return String(path || '')\r\n      .split('?')[0]\r\n      .split('#')[0]\r\n      .replace(\/\\\/+$\/, '')\r\n      .toLowerCase();\r\n  }\r\n\r\n  function highlightActive() {\r\n    var sidebar = document.querySelector('.ols-sidebar');\r\n    if (!sidebar) return false;\r\n\r\n    var currentPath = normalisePath(window.location.pathname);\r\n    var links = sidebar.querySelectorAll('a[href]');\r\n    var matched = null;\r\n    var matchedLength = 0;\r\n\r\n    sidebar.querySelectorAll('.active, .active-main, .parent-active').forEach(function(item) {\r\n      item.classList.remove('active', 'active-main', 'parent-active');\r\n    });\r\n\r\n    sidebar.querySelectorAll('a[data-ols-disabled-parent=\"1\"], a[aria-current]').forEach(function(a) {\r\n      a.removeAttribute('aria-current');\r\n      a.removeAttribute('tabindex');\r\n      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}\r\n})();\r\n<\/script>\r\n\n\n    <main class=\"ols-main\">\n\n      <!-- BREADCRUMBS - updated with full path and correct links -->\n      <nav class=\"ols-breadcrumbs\" aria-label=\"Breadcrumb\">\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/\">Revision Notes<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/\">A Level Chemistry<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">Edexcel International<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/\">Topic 9 Kinetics and Equilibria<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/\">Topic 9A Kinetics<\/a> \/\n<span>Catalysts and Reaction Profiles<\/span>\n<\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Catalysts and Reaction Profiles<\/h1>\n        <p class=\"ols-page-intro\">A concise revision guide to catalysts: alternative routes of lower activation energy, reaction profiles for uncatalysed and catalysed reactions including the intermediate, homogeneous and heterogeneous catalysts, and why industry uses them.<\/p>\n        <div class=\"ols-badges\">\n<div class=\"ols-badge\">Exam board: Edexcel International<\/div>\n<div class=\"ols-badge\">Unit 2: WCH12\/01<\/div>\n<div class=\"ols-badge\">Topic 9A Kinetics<\/div>\n<\/div>\n        <div class=\"ols-author\">\n\n    <img decoding=\"async\"\n      class=\"ols-author-avatar-img\"\n      src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\"\n      alt=\"Dr. Mohammed Al-Fatah\"\n    >\n\n    <div class=\"ols-author-content\">\n\n      <h2 class=\"ols-author-title\">\n        Written by: Dr. Mohammed Al-Fatah\n      <\/h2>\n\n      <p class=\"ols-author-description\">\n        Chemistry specialist revision notes for A Level Chemistry.\n      <\/p>\n\n      <a class=\"ols-linkedin-pill\" href=\"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\" target=\"_blank\" rel=\"noopener noreferrer\">\n        <svg class=\"ols-linkedin-icon\" viewBox=\"0 0 24 24\" fill=\"currentColor\" aria-hidden=\"true\">\n          <path d=\"M4.98 3.5C4.98 4.88 3.86 6 2.48 6S0 4.88 0 3.5 1.12 1 2.48 1s2.5 1.12 2.5 2.5zM.5 8h4V24h-4V8zm7 0h3.8v2.2h.1c.5-.9 1.8-2.2 3.9-2.2 4.2 0 5 2.8 5 6.4V24h-4v-7.6c0-1.8 0-4.2-2.6-4.2s-3 2-3 4v7.8h-4V8z\"\/>\n        <\/svg>\n        View LinkedIn Profile\n      <\/a>\n\n    <\/div>\n\n  <\/div>\n      <\/header>\n\n      <article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">1<\/div>\n<h2>What a Catalyst Does<\/h2>\n<\/div>\n<p>A <strong>catalyst<\/strong> is a substance that increases the rate of a reaction without being used up.<\/p><p>It takes part in the reaction, but it is regenerated by the end, so a small amount of catalyst can convert a very large amount of reactant.<\/p><p>The catalyst works by providing an <strong>alternative reaction route<\/strong> (a different mechanism) with a <strong>lower activation energy<\/strong>, so that a greater proportion of collisions have enough energy to react.<\/p>\n<p>A catalyst does not change the products, the amount of product, or the enthalpy change of the reaction, and it does not make an impossible reaction possible.<\/p><p>It only changes how quickly the reaction reaches its end point. In a reversible reaction it speeds up the forward and reverse reactions equally, which matters for equilibria later in this topic.<\/p>\n<div class=\"ols-key-box\">\n<p><strong>Definition:<\/strong> A catalyst increases the rate of a reaction by providing an alternative route with a lower activation energy, and is chemically unchanged at the end of the reaction.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card soft\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">2<\/div>\n<h2>Reaction profiles for Catalysed Reactions<\/h2>\n<\/div>\n<p>A <strong>reaction profile<\/strong> plots energy against the progress of the reaction. The reactants sit at one level, the products at another (lower for an exothermic reaction, higher for an endothermic one), and the curve between them rises over an energy barrier whose height above the reactants is the activation energy.<\/p>\n<p>The catalysed route is drawn on the same axes as a second curve with a lower barrier.<\/p><p>Because the catalyst takes part in the reaction, the catalysed route usually has two smaller humps with a dip between them. The dip is the energy level of the <strong>intermediate<\/strong> formed between the catalyst and a reactant.<\/p><p>The activation energy of the catalysed route is measured to the higher of the two small peaks. The start and finish levels, and therefore \u0394H, are exactly the same on both routes.<\/p>\n<div class=\"ols-figure-card ols-zoom-pop\">\n<div class=\"ols-figure-image\">\n<a class=\"ols-image-fullscreen-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/kinetics-equilibria-catalysed-reaction-profile.jpg\" target=\"_blank\" rel=\"noopener\" aria-label=\"Open image fullscreen\">\n<img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/kinetics-equilibria-catalysed-reaction-profile.jpg\" alt=\"Reaction profile for an exothermic reaction with the uncatalysed route and the lower catalysed route via an intermediate; \u0394H unchanged\" data-fullscreen-src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/kinetics-equilibria-catalysed-reaction-profile.jpg\">\n<\/a>\n<\/div>\n<div class=\"ols-figure-caption\"><p>A reaction profile for an exothermic reaction showing the uncatalysed route and the lower catalysed route with its intermediate.<\/p><\/div>\n<\/div>\n<div class=\"ols-key-box\">\n<p><strong>Exam focus:<\/strong> Draw the catalysed route starting and finishing at the same levels as the uncatalysed one, with a lower peak. If asked to show the intermediate, put a dip between two humps and label it.<\/p>\n<\/div>\n<\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Check: Reading a Profile<\/h2>\n<p>Interpret reaction profiles for reactions not drawn on this page.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-content\" data-content-id=\"908\"><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">3<\/div>\n<h2>Homogeneous and Heterogeneous Catalysts<\/h2>\n<\/div>\n<p>A <strong>homogeneous catalyst<\/strong> is in the same phase as the reactants, usually all in solution or all gases.<\/p><p>It reacts with a reactant to form an intermediate, which then breaks down to give the product and regenerate the catalyst.<\/p><p>Sulfuric acid catalysing the formation of an ester from an alcohol and a carboxylic acid is a homogeneous catalyst.<\/p>\n<p>A <strong>heterogeneous catalyst<\/strong> is in a different phase from the reactants, most often a solid catalysing a reaction between gases.<\/p><p>The reactant molecules are <strong>adsorbed<\/strong> onto active sites on the surface, where their bonds are weakened. The atoms react on the surface and the product then leaves it (<strong>desorption<\/strong>).<\/p><p>Iron in the Haber process, vanadium(V) oxide in the Contact process and the platinum\u2013rhodium in a car&#8217;s catalytic converter all work this way.<\/p><p>A solid catalyst is easy to separate from the products and can be used in a continuous process, but its surface can be <strong>poisoned<\/strong> by impurities that block the active sites.<\/p>\n<!-- 3D card: haber-catalysis (26 Sep 2026) -->\n<!-- Copyright (c) 2026 Dr. Mohammed Al-Fatah, onlinelearningsystem.net. 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right:14px; transform:none; font-size:11px; padding:6px 10px;}\n}\n\/* on a phone the caption needs the full top row, so the drag hint goes *\/\n@media (max-width:480px){\n  .ols-hab-001 .hab-hint{display:none;}\n}\n@media (prefers-reduced-motion:reduce){\n  .ols-hab-001 .hab-seg button,.ols-hab-001 .hab-pill{transition:none;}\n}\n\n.ols-cc-hab-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  margin:10px auto 0; text-align:center; font-size:11px; font-style:italic; color:#aab0c0;\n}\n.ols-cc-hab-001 a{color:#aab0c0; text-decoration:none;}\n.ols-cc-hab-001 a:hover{text-decoration:underline;}\n<\/style>\n\n<div class=\"hab-head\">\n  <h2 class=\"hab-title\">Heterogeneous Catalysis on an Iron Surface<\/h2>\n  <p class=\"hab-sub\">Follow nitrogen and hydrogen through the Haber process on iron: adsorption, bond breaking, reaction on the surface and desorption of ammonia.<\/p>\n<\/div>\n\n<div class=\"hab-stage\" id=\"habStage\">\n  <canvas class=\"hab-canvas\" id=\"habCanvas\"><\/canvas>\n  <div class=\"hab-overlay\" id=\"habOverlay\"><\/div>\n  <div class=\"hab-caption\" id=\"habCaption\"><\/div>\n  <div class=\"hab-hint\" id=\"habHint\">Drag to rotate<\/div>\n  <div class=\"hab-badges\" id=\"habBadges\"><\/div>\n<\/div>\n\n<div class=\"hab-controls\">\n  <div class=\"hab-row\">\n    <span class=\"hab-rowlab\">Step<\/span>\n    <div class=\"hab-seg\" role=\"group\" aria-label=\"Step\">\n      <button type=\"button\" data-step=\"1\" aria-pressed=\"true\">Adsorb<\/button>\n      <button type=\"button\" data-step=\"2\" aria-pressed=\"false\">Weaken<\/button>\n      <button type=\"button\" data-step=\"3\" aria-pressed=\"false\">React<\/button>\n      <button type=\"button\" data-step=\"4\" aria-pressed=\"false\">Desorb<\/button>\n      <button type=\"button\" data-step=\"5\" aria-pressed=\"false\">Promoter<\/button>\n      <button type=\"button\" data-step=\"6\" aria-pressed=\"false\">Poison<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"hab-row\">\n    <span class=\"hab-rowlab\">View<\/span>\n    <button type=\"button\" class=\"hab-pill\" id=\"habResetV\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"hab-info\">\n  <h3 id=\"habInfoTitle\"><\/h3>\n  <p id=\"habInfoText\"><\/p>\n  <div class=\"hab-facts\" id=\"habFacts\"><\/div>\n  <div class=\"hab-key\">\n    <span><i style=\"background:#969caa\"><\/i>Iron, Fe<\/span>\n    <span><i style=\"background:#3462c8\"><\/i>Nitrogen<\/span>\n    <span><i style=\"background:#eef0f5\"><\/i>Hydrogen<\/span>\n    <span><i style=\"background:#8f40d4\"><\/i>Potassium promoter<\/span>\n    <span><i style=\"background:#bfa6a6\"><\/i>Aluminium oxide promoter<\/span>\n    <span><i style=\"background:#dcbe28\"><\/i>Sulfur poison<\/span>\n    <span><i style=\"background:#ffffff; border:2px solid #2f9e57; border-radius:50%\"><\/i>Free active site<\/span>\n    <span><i style=\"background:#ffffff; border:2px solid #d9433a; border-radius:50%\"><\/i>Blocked site<\/span>\n    <span><i style=\"background:#e83c34\"><\/i>Bond breaking<\/span>\n    <span><i style=\"background:#38b258\"><\/i>Bond forming<\/span>\n    <span><i style=\"background:#ffffff; border:1.5px dashed rgba(28,36,75,0.7)\"><\/i>Bond to the surface<\/span>\n  <\/div>\n<\/div>\n<\/section>\n\n<p class=\"ols-cc-hab-001\">&copy; Dr. Mohammed Al-Fatah &#8211; <a href=\"https:\/\/www.onlinelearningsystem.net\" target=\"_blank\" rel=\"noopener\">onlinelearningsystem.net<\/a><\/p>\n<script src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/JS\/haber-catalysis.js?v=20261003e\"><\/script>\n\n<div class=\"ols-key-box\">\n<p><strong>Key idea:<\/strong> Homogeneous: same phase, works through an intermediate. Heterogeneous: different phase, works at surface active sites by adsorption.<\/p>\n<\/div>\n<\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Check: Sorting Catalysts<\/h2>\n<p>Classify catalysts and describe how a solid catalyst works, using examples not given above.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-content\" data-content-id=\"909\"><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card soft\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">4<\/div>\n<h2>Why Industry Uses Catalysts<\/h2>\n<\/div>\n<p>Catalysts make industrial processes cheaper and more sustainable.<\/p><p>Because they lower the activation energy, a reaction can run at an acceptable rate at a <strong>lower temperature<\/strong>, so <strong>less energy<\/strong> is needed, less fossil fuel is burned to supply it and less carbon dioxide is released.<\/p><p>Lower temperatures and pressures also mean cheaper, safer plant.<\/p>\n<p>A catalyst can also make a process more <strong>atom economical<\/strong> by steering the reaction to the wanted product and away from by-products. More of the starting material ends up in the product and less waste is made.<\/p><p>Because the catalyst is not used up it does not need constant replacing, although in practice catalysts are replaced when they become poisoned or lose their surface area.<\/p>\n\n<div class=\"ols-key-box\">\n<p><strong>Exam wording:<\/strong> Link each benefit to the cause: &#8220;lower activation energy \u2192 lower temperature \u2192 less energy \u2192 less fossil fuel burned \u2192 less CO\u2082&#8221;. &#8220;Higher atom economy \u2192 less waste.&#8221;<\/p>\n<\/div>\n<div class=\"ols-figure-card ols-zoom-pop\">\n<div class=\"ols-figure-image\">\n<a class=\"ols-image-fullscreen-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/t9x-catbenefits.jpg\" target=\"_blank\" rel=\"noopener\" aria-label=\"Open image fullscreen\">\n<img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/t9x-catbenefits.jpg\" alt=\"Benefit chains from lower activation energy to less CO\u2082 and from selectivity to less waste, with economic and environmental columns.\" data-fullscreen-src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/t9x-catbenefits.jpg\">\n<\/a>\n<\/div>\n<div class=\"ols-figure-caption\"><p>A catalyst lets a process run at a lower temperature with less energy and less carbon dioxide, and by favouring the wanted product it raises the atom economy and cuts waste.<\/p><\/div>\n<\/div>\n<\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Check: Catalysts in Industry<\/h2>\n<p>Explain the benefits of catalysts for a process not described above.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-910\" class=\"h5p-iframe\" data-content-id=\"910\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Kinetics and Equilibria MCQ: Catalysts in Industry\"><\/iframe><\/div><\/div>\n<\/section>\n<section class=\"ols-faq-card\">\n<h2>FAQs<\/h2>\n<p>Use these quick answers to check the catalyst ideas.<\/p>\n\n<div class=\"ols-faq-list\">\n<div class=\"ols-faq-item\">\n<h3>Is a catalyst used up?<\/h3>\n<p>No. It takes part in the reaction but is regenerated, so it is chemically unchanged at the end and the same amount is present.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>Does a catalyst change \u0394H?<\/h3>\n<p>No. The reactants and products are the same, so the enthalpy change is the same. Only the activation energy is lower.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>Why does the catalysed route on a reaction profile have two humps?<\/h3>\n<p>Because the catalyst forms an intermediate with a reactant, which then breaks down to give the product. The dip between the humps is the energy of the intermediate.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>What is the difference between a homogeneous and a heterogeneous catalyst?<\/h3>\n<p>A homogeneous catalyst is in the same phase as the reactants, such as an acid in solution; a heterogeneous catalyst is in a different phase, such as a solid catalysing a gas reaction at its surface.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>How does a catalyst reduce carbon dioxide emissions?<\/h3>\n<p>It lets the reaction run at an acceptable rate at a lower temperature, so less fuel is burned to heat the plant and less carbon dioxide is produced.<\/p>\n<\/div>\n<\/div>\n<\/section>\n<section class=\"ols-related-card\">\n<h2>Related Topic 9A Kinetics Pages<\/h2>\n<p>Use these pages to connect the ideas across kinetics and the rest of Topic 9.<\/p>\n<div class=\"ols-related-grid\">\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/collision-theory-and-rates-of-reaction\/\">Collision Theory and Rates of Reaction<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/measuring-and-calculating-rates\/\">Measuring and Calculating Rates<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/maxwell-boltzmann-distribution\/\">The Maxwell\u2013Boltzmann Distribution<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-9-kinetics-and-equilibria\/9a-kinetics\/\">Topic 9A Kinetics Overview<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/enthalpy-changes-and-standard-conditions\/\">Enthalpy Changes and Reaction Profiles (Topic 6)<\/a>\n<\/div>\n<\/section>\n<section class=\"ols-attribution-card\">\n        <p><strong>Copyright notice:<\/strong> This OLS revision content, including the explanations, layout, diagrams, tables and embedded learning structure, is authored for Online Learning System by Dr. Mohammed Al-Fatah. 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