{"id":8358,"date":"2026-09-18T12:01:11","date_gmt":"2026-09-18T11:01:11","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/calorimetry-measuring-enthalpy-changes\/"},"modified":"2026-09-18T12:09:24","modified_gmt":"2026-09-18T11:09:24","slug":"calorimetry-measuring-enthalpy-changes","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/calorimetry-measuring-enthalpy-changes\/","title":{"rendered":"Calorimetry: Measuring Enthalpy Changes"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-nature-of-covalent-bonding-9ch0-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      --soft-orange: #fff7ed;\n      --grey-text: #667085;\n      --body-text: 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border-radius: 22px; padding: 14px; margin: 18px 0 6px; }\n    .ols-figure-placeholder .ols-figure-caption p { margin: 10px 0 0; font-size: 14px; color: #667085; text-align: center; }\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>3.1.4 Energetics<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/\">3.1.4 Overview<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/enthalpy-changes-and-standard-conditions\/\">Enthalpy Changes and Standard Conditions<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/standard-enthalpy-changes\/\">Standard Enthalpy Changes<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/calorimetry-measuring-enthalpy-changes\/\">Calorimetry: Measuring Enthalpy Changes<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/hess-law-and-enthalpy-cycles\/\">Hess's Law and Enthalpy Cycles<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/bond-enthalpies\/\">Bond Enthalpies<\/a>\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\/aqa\/3-1-2-amount-of-substance\/\">3.1.2 Amount of Substance<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-3-bonding\/\">3.1.3 Bonding<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-2-1-periodicity\/\">3.2.1 Periodicity<\/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 = 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href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/\">3.1.4 Energetics<\/a> \/\n<span>Calorimetry: Measuring Enthalpy Changes<\/span>\n<\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Calorimetry: Measuring Enthalpy Changes<\/h1>\n        <p class=\"ols-page-intro\">A concise revision guide to measuring enthalpy changes by calorimetry: q = mc\u0394T, converting to kJ mol\u207b\u00b9, the cooling-curve correction, and evaluating errors and assumptions, for AQA A Level Chemistry.<\/p>\n\n        <div class=\"ols-badges\">\n<div class=\"ols-badge\">Paper 1 and 2 AQA<\/div>\n<div class=\"ols-badge\">3.1.4 Energetics<\/div>\n<div class=\"ols-badge\">7405\/1 and 7405\/2<\/div>\n<\/div>\n\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:<br><span>Dr. Mohammed Al-Fatah<\/span>\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 soft\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">1<\/div>\n<h2>The Key Equation: q = mc\u0394T<\/h2>\n<\/div>\n<p>A <strong>calorimetry<\/strong> experiment measures the temperature change of a known mass of water or solution and uses it to calculate the energy transferred:<\/p>\n<div class=\"ols-key-box\">\n<p><strong>Key equation:<\/strong> q = m \u00d7 c \u00d7 \u0394T<\/p>\n<\/div>\n<div class=\"ols-table-wrap\">\n<table class=\"ols-table\">\n<thead>\n<tr><th>Symbol<\/th><th>Meaning<\/th><th>Units<\/th><\/tr>\n<\/thead>\n<tbody>\n<tr><td><strong>q<\/strong><\/td><td>energy transferred to or from the surroundings<\/td><td>J<\/td><\/tr>\n<tr><td><strong>m<\/strong><\/td><td>mass of the water or solution being heated or cooled (not the mass of the reactants)<\/td><td>g<\/td><\/tr>\n<tr><td><strong>c<\/strong><\/td><td>specific heat capacity; 4.18 J g\u207b\u00b9 K\u207b\u00b9 for water and dilute solutions<\/td><td>J g\u207b\u00b9 K\u207b\u00b9<\/td><\/tr>\n<tr><td><strong>\u0394T<\/strong><\/td><td>temperature change; a change of 1 K equals a change of 1 \u00b0C<\/td><td>K<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>For dilute aqueous solutions it is assumed that the density is 1.00 g cm\u207b\u00b3, so 50.0 cm\u00b3 of solution has a mass of 50.0 g, and that the specific heat capacity is the same as that of water.<\/p>\n<div class=\"ols-key-box\">\n<p><strong>Common mistake:<\/strong> Using the mass of the solid added as m. The energy heats the water or solution, so m is the mass of the liquid.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">2<\/div>\n<h2>From q to the Enthalpy Change<\/h2>\n<\/div>\n<p>q gives the energy for the amounts used in the experiment. To find the enthalpy change in kJ mol\u207b\u00b9:<\/p>\n<ol>\n<li>Calculate q = mc\u0394T in joules.<\/li>\n<li>Calculate the moles of the reactant that is <strong>not in excess<\/strong>.<\/li>\n<li>Divide q by those moles and convert to kJ by dividing by 1000.<\/li>\n<li>Add the sign: <strong>negative<\/strong> if the temperature rose (exothermic), positive if it fell.<\/li>\n<\/ol>\n\n<div class=\"ols-key-box\">\n<p><strong>Exam sentence:<\/strong> Both a sign and units are required in the final answer, for example \u0394H = \u221256.8 kJ mol\u207b\u00b9. An answer without a sign is incomplete.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card purple\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">3<\/div>\n<h2>Worked Example 1: Reaction in Solution<\/h2>\n<\/div>\n<p>50.0 cm\u00b3 of 1.00 mol dm\u207b\u00b3 hydrochloric acid is mixed with 50.0 cm\u00b3 of 1.10 mol dm\u207b\u00b3 sodium hydroxide in a polystyrene cup. The temperature rises by 6.8 K. Calculate the enthalpy change of neutralisation.<\/p>\n<ol>\n<li>Mass of solution = 100.0 g; q = 100.0 \u00d7 4.18 \u00d7 6.8 = 2842 J<\/li>\n<li>n(HCl) = 1.00 \u00d7 50.0 \u00f7 1000 = 0.0500 mol; the alkali is in excess, so 0.0500 mol of water forms<\/li>\n<li>\u0394H = \u22122842 \u00f7 0.0500 = \u221256 840 J mol\u207b\u00b9 = <strong>\u221256.8 kJ mol\u207b\u00b9<\/strong><\/li>\n<\/ol>\n<div class=\"ols-key-box\">\n<p><strong>Key idea:<\/strong> Add the volumes of both solutions to get the mass heated. Divide by the moles of the reagent that is used up, not the one in excess.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">4<\/div>\n<h2>Worked Example 2: Combustion of a Fuel<\/h2>\n<\/div>\n<p>Burning 0.460 g of ethanol, C\u2082H\u2085OH, from a spirit burner raises the temperature of 100 g of water in a copper can by 20.0 K. Calculate the enthalpy change of combustion.<\/p>\n<ol>\n<li>q = 100 \u00d7 4.18 \u00d7 20.0 = 8360 J<\/li>\n<li>n(C\u2082H\u2085OH) = 0.460 \u00f7 46.0 = 0.0100 mol<\/li>\n<li>\u0394H = \u22128360 \u00f7 0.0100 = \u2212836 000 J mol\u207b\u00b9 = <strong>\u2212836 kJ mol\u207b\u00b9<\/strong><\/li>\n<\/ol>\n<p>The data book value is \u22121367 kJ mol\u207b\u00b9. The experimental value is far less exothermic because much of the energy heats the air and the can rather than the water, and some ethanol burns incompletely. Combustion calorimetry nearly always underestimates the enthalpy change.<\/p>\n<div class=\"ols-key-box\">\n<p><strong>Exam focus:<\/strong> When asked why an experimental value is less exothermic than the data value, give heat loss to the surroundings first, then incomplete combustion or evaporation of the fuel.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card soft\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">5<\/div>\n<h2>Correcting for Heat Loss: the Cooling Curve<\/h2>\n<\/div>\n<p>In a slower reaction the solution starts losing heat before the maximum temperature is reached, so the highest reading is too low. The correction is to take readings every minute before and after mixing, plot temperature against time, draw a best-fit line through the cooling points and <strong>extrapolate<\/strong> it back to the time of mixing. The temperature change is read from the graph at that time.<\/p>\n<div class=\"ols-zoom-card\">\n<div class=\"ols-zoom-card-image\">\n<a class=\"ols-lightbox-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/06\/measuring-temperature-change-accurately.webp\" aria-label=\"Open image full screen\">\n<img decoding=\"async\" class=\"ols-zoomable-img ols-lightbox-target\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/06\/measuring-temperature-change-accurately.webp\" alt=\"Graphical explanation of measuring temperature change accurately in calorimetry experiments\">\n<\/a>\n<\/div>\n<div class=\"ols-zoom-card-caption\"><p>Extrapolating the cooling line back to the moment of mixing gives the temperature rise that would have been reached with no heat loss.<\/p><\/div>\n<\/div>\n<div class=\"ols-key-box\">\n<p><strong>Remember:<\/strong> Record the starting temperature for a few minutes before mixing; if two solutions are used, measure both and take the mean.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">6<\/div>\n<h2>Errors, Assumptions and Technique<\/h2>\n<\/div>\n<p>Questions often ask you to evaluate the method. The main sources of error and the assumptions made are:<\/p>\n<div class=\"ols-table-wrap\">\n<table class=\"ols-table\">\n<thead>\n<tr><th>Source<\/th><th>Effect<\/th><th>Improvement<\/th><\/tr>\n<\/thead>\n<tbody>\n<tr><td><strong>Heat lost to the surroundings<\/strong><\/td><td>\u0394T too small, so \u0394H not exothermic enough<\/td><td>lid on the cup, insulate, use the cooling-curve correction<\/td><\/tr>\n<tr><td><strong>Heat absorbed by the cup or can<\/strong><\/td><td>ignored in the calculation<\/td><td>use a polystyrene cup, which has a very low heat capacity<\/td><\/tr>\n<tr><td><strong>Solution assumed to have c = 4.18 J g\u207b\u00b9 K\u207b\u00b9 and density 1.00 g cm\u207b\u00b3<\/strong><\/td><td>small systematic error<\/td><td>accept as a stated assumption<\/td><\/tr>\n<tr><td><strong>Incomplete reaction or incomplete combustion<\/strong><\/td><td>less energy released<\/td><td>stir; use excess of one reagent; ensure a good oxygen supply<\/td><\/tr>\n<tr><td><strong>Thermometer resolution<\/strong><\/td><td>large percentage uncertainty in small \u0394T<\/td><td>use a 0.1 \u00b0C thermometer or a larger \u0394T<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<div class=\"ols-zoom-card\">\n<div class=\"ols-zoom-card-image\">\n<a class=\"ols-lightbox-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/06\/measuring-enthalpy-change-by-calorimetry.webp\" aria-label=\"Open image full screen\">\n<img decoding=\"async\" class=\"ols-zoomable-img ols-lightbox-target\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/06\/measuring-enthalpy-change-by-calorimetry.webp\" alt=\"Overview of calorimetry methods for measuring enthalpy changes in chemical reactions\">\n<\/a>\n<\/div>\n<div class=\"ols-zoom-card-caption\"><p>The calorimetric method in one view: the equation, the practical steps, the calculation and the main limitations.<\/p><\/div>\n<\/div>\n<p>This method is assessed in the enthalpy change required practical, which uses measured temperature changes to find an enthalpy change.<\/p>\n<div class=\"ols-key-box\">\n<p><strong>Exam sentence:<\/strong> The value is less exothermic than expected because heat is lost to the surroundings, so the measured temperature rise is smaller than the true value.<\/p>\n<\/div>\n<\/article>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">7<\/div>\n<h2>Common Exam Points<\/h2>\n<\/div>\n<h3>Calculate an enthalpy change from a temperature rise<\/h3><p>q = mc\u0394T with the mass of solution, divide by moles of the reagent not in excess, convert to kJ, add a negative sign.<\/p>\n<h3>Explain the extrapolation on a temperature-time graph<\/h3><p>It corrects for heat lost while the reaction is still taking place, giving the temperature at the moment of mixing.<\/p>\n<h3>Suggest why the experimental value differs from the data value<\/h3><p>Heat loss to the surroundings, heat absorbed by the apparatus, incomplete reaction or combustion.<\/p>\n<h3>Do not say<\/h3><p>&#8220;Human error&#8221;; &#8220;m is the mass of the solid&#8221;; an answer with no sign.<\/p>\n<\/article>\n<section class=\"ols-h5p-card\">\n<h2>Check Your Understanding<\/h2>\n<p>Work through new calorimetry data rather than the worked examples above.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-554\" class=\"h5p-iframe\" data-content-id=\"554\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Energetics Drag: calorimetry method\"><\/iframe><\/div><\/div>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-555\" class=\"h5p-iframe\" data-content-id=\"555\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Energetics MCQ: zinc and copper sulfate\"><\/iframe><\/div><\/div>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-556\" class=\"h5p-iframe\" data-content-id=\"556\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Energetics MCQ: combustion of propan-1-ol\"><\/iframe><\/div><\/div>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-557\" class=\"h5p-iframe\" data-content-id=\"557\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Energetics MCQ: extrapolating a cooling line\"><\/iframe><\/div><\/div>\n<\/section>\n<section class=\"ols-faq-card\">\n<h2>FAQs<\/h2>\n<p>Use these quick answers to check the calorimetry calculations and practical points.<\/p>\n\n<div class=\"ols-faq-list\">\n<div class=\"ols-faq-item\">\n<h3>What mass goes into q = mc\u0394T?<\/h3>\n<p>The mass of the water or solution being heated. For dilute solutions, 1 cm\u00b3 is taken to have a mass of 1 g.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>Why is the answer negative when the temperature rises?<\/h3>\n<p>A temperature rise shows energy was released to the surroundings, so the reaction is exothermic and \u0394H is negative.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>Which moles do I divide by?<\/h3>\n<p>The moles of the reactant that is not in excess, because that decides how much reaction takes place.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>Why are experimental values usually less exothermic than data book values?<\/h3>\n<p>Heat is lost to the surroundings and absorbed by the apparatus, so the measured temperature change is smaller than the true value.<\/p>\n<\/div>\n\n<div class=\"ols-faq-item\">\n<h3>Why use a polystyrene cup?<\/h3>\n<p>It is a good insulator and has a very low heat capacity, so little energy is lost through it or used to heat it.<\/p>\n<\/div>\n<\/div>\n<\/section>\n<section class=\"ols-related-card\">\n<h2>Related Energetics Pages<\/h2>\n<p>Use these pages to connect enthalpy definitions, measurement and calculation methods across the topic.<\/p>\n<div class=\"ols-related-grid\">\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/enthalpy-changes-and-standard-conditions\/\">Enthalpy Changes and Standard Conditions<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/standard-enthalpy-changes\/\">Standard Enthalpy Changes<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/hess-law-and-enthalpy-cycles\/\">Hess&#8217;s Law and Enthalpy Cycles<\/a>\n<a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/aqa\/3-1-4-energetics\/bond-enthalpies\/\">Bond Enthalpies<\/a>\n<\/div>\n<\/section>\n<section class=\"ols-attribution-card\">\n        <p><strong>Copyright and author footprint:<\/strong> This OLS revision page was written for Online Learning System by <strong>Dr. Mohammed Al-Fatah<\/strong>. It is designed for A Level Chemistry revision and should not be copied or redistributed without permission.<\/p>\n      <\/section>\n\n      <div class=\"ols-image-lightbox\" id=\"olsImageLightboxNatureCovalentBonding9ch0\" aria-hidden=\"true\" role=\"dialog\" aria-modal=\"true\" aria-label=\"Expanded revision image\">\n        <div class=\"ols-image-lightbox-inner\">\n          <button class=\"ols-image-lightbox-close\" type=\"button\" aria-label=\"Close enlarged image\">\u00d7<\/button>\n          <img decoding=\"async\" class=\"ols-image-lightbox-img\" src=\"\" alt=\"\">\n        <\/div>\n      <\/div>\n\n      <script>\n        (function(){\n          var page = document.querySelector(\".ols-nature-of-covalent-bonding-9ch0-page\");\n          if (!page) { return; }\n          var lightbox = page.querySelector(\"#olsImageLightboxNatureCovalentBonding9ch0\");\n          if (!lightbox) { return; }\n          var lightboxImage = lightbox.querySelector(\".ols-image-lightbox-img\");\n    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Paper 1 and 2 AQA [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":8355,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-8358","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/8358","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/comments?post=8358"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/8358\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/8355"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=8358"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}