{"id":3157,"date":"2026-05-04T17:56:55","date_gmt":"2026-05-04T16:56:55","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/?page_id=3157"},"modified":"2026-10-12T11:38:49","modified_gmt":"2026-10-12T10:38:49","slug":"topic-6-energetics","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/","title":{"rendered":"Topic 6 Energetics"},"content":{"rendered":"\n<div class=\"ols-t6-page\">\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 6 Energetics<\/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 Overview<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-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\/edexcel-international\/topic-6-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\/edexcel-international\/topic-6-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\/edexcel-international\/topic-6-energetics\/hess-law-and-enthalpy-cycles\/\">Hess's Law and Enthalpy Cycles<\/a>\n      <\/li>\n      <li>\n        <a 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margin-top: 10px;\n    }\n\n    .ols-t6-spec-mob-sub-row {\n      background: #ffffff;\n      border: 1px solid rgba(70, 127, 247, 0.15);\n      border-radius: 12px;\n      overflow: hidden;\n    }\n\n    .ols-t6-spec-mob-sub-code {\n      background: #93b5f8;\n      color: #0c2060;\n      font-size: 13px;\n      font-weight: 800;\n      text-align: center;\n      height: 30px;\n      line-height: 30px;\n    }\n\n    .ols-t6-spec-mob-sub-text {\n      padding: 12px 16px;\n      font-size: 14px;\n      font-weight: 300;\n      line-height: 1.8;\n      color: #4b5563;\n    }\n\n    \/* =========================================================\n       RESPONSIVE\n    ========================================================= *\/\n\n    @media (max-width: 1024px) {\n      .ols-t6-cards-grid {\n        grid-template-columns: repeat(2, minmax(0, 1fr));\n      }\n    }\n\n    @media (max-width: 860px) {\n      .ols-t6-intro-inner {\n        grid-template-columns: 1fr;\n        gap: 40px;\n      }\n    }\n\n    @media (max-width: 640px) {\n      .ols-t6-intro {\n        padding: 24px 0 52px;\n      }\n\n      .ols-t6-topics {\n        padding: 52px 0 58px;\n      }\n\n      .ols-t6-cards-grid {\n        grid-template-columns: 1fr;\n        gap: 14px;\n      }\n\n      .ols-t6-spec-section {\n        padding: 52px 0 64px;\n      }\n\n      .ols-t6-spec-wrap {\n        padding: 24px 18px;\n        border-radius: 20px;\n      }\n\n      .ols-t6-info-grid {\n        grid-template-columns: 1fr 1fr;\n      }\n    }\n\n  <\/style>\n\n  <!-- BREADCRUMB BAR - sits above everything -->\n  <div class=\"ols-t6-breadcrumb-bar\">\n    <div class=\"ols-t6-container\">\n      <nav class=\"ols-t6-breadcrumb\" 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          <span>Topic 6 Energetics<\/span>\n        <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t6-intro\">\n    <div class=\"ols-t6-container\">\n      <div class=\"ols-t6-intro-inner\">\n\n        <div>\n          <div class=\"ols-t6-eyebrow\">Edexcel International A Level Chemistry<\/div>\n          <h1>Topic 6<br>Energetics<\/h1>\n          <div class=\"ols-t6-accent-bar\"><\/div>\n          <p class=\"ols-t6-intro-lead\">\n            Energetics is the study of the heat energy transferred when chemicals react. This topic covers exothermic and endothermic reactions, enthalpy level diagrams, the standard enthalpy change definitions, measuring enthalpy changes by calorimetry, Hess&#8217;s law and enthalpy cycles, and bond enthalpies, all examined in Unit 2 and assessed practically through Core Practical 2.\n          <\/p>\n        <\/div>\n\n        <div class=\"ols-t6-info-grid\">\n          <div class=\"ols-t6-info-card\">\n            <div class=\"ols-t6-info-card-label\">Exam Unit<\/div>\n            <div class=\"ols-t6-info-card-value\">Unit 2<\/div>\n            <div class=\"ols-t6-info-card-sub\">WCH12\/01 &#8211; IAS<\/div>\n          <\/div>\n          <div class=\"ols-t6-info-card\">\n            <div class=\"ols-t6-info-card-label\">Specification Points<\/div>\n            <div class=\"ols-t6-info-card-value\">6.1 &#8211; 6.11<\/div>\n            <div class=\"ols-t6-info-card-sub\">11 points covered<\/div>\n          <\/div>\n          <div class=\"ols-t6-info-card\">\n            <div class=\"ols-t6-info-card-label\">Sub-topics<\/div>\n            <div class=\"ols-t6-info-card-value\">5 pages<\/div>\n            <div class=\"ols-t6-info-card-sub\">Revision notes available<\/div>\n          <\/div>\n          <div class=\"ols-t6-info-card\">\n            <div class=\"ols-t6-info-card-label\">Exam Board<\/div>\n            <div class=\"ols-t6-info-card-value\">Edexcel IAL<\/div>\n            <div class=\"ols-t6-info-card-sub\">Pearson International<\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-t6-topics\">\n    <div class=\"ols-t6-container\">\n\n      <div class=\"ols-t6-section-header\">\n        <h2 class=\"ols-t6-section-title\">Revision Notes<\/h2>\n      <\/div>\n\n      <div class=\"ols-t6-cards-grid\">\n\n        <!-- Card 1: Enthalpy Changes and Standard Conditions -->\n        <a class=\"ols-t6-card ols-t6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/enthalpy-changes-and-standard-conditions\/\">\n          <div class=\"ols-t6-card-img-wrap\">\n            <div class=\"ols-t6-visual ols-t6-visual--mechanism\">\n              <div class=\"ols-t6-visual-panel\">\n                <div class=\"ols-t6-visual-kicker\">Exo and endo<\/div>\n                <div class=\"ols-t6-visual-main\">Enthalpy<br>Changes<\/div>\n                <div class=\"ols-t6-visual-sub\">\u0394H, level diagrams, 100 kPa<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t6-card-num\">1<\/div>\n          <\/div>\n          <div class=\"ols-t6-card-body\">\n            <p class=\"ols-t6-card-title\">Enthalpy Changes and Standard Conditions<\/p>\n            <p class=\"ols-t6-card-desc\">Exothermic and endothermic reactions, enthalpy level diagrams, activation energy and standard conditions.<\/p>\n            <span class=\"ols-t6-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 2: Standard Enthalpy Changes -->\n        <a class=\"ols-t6-card ols-t6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/standard-enthalpy-changes\/\">\n          <div class=\"ols-t6-card-img-wrap\">\n            <div class=\"ols-t6-visual ols-t6-visual--bonding\">\n              <div class=\"ols-t6-visual-panel\">\n                <div class=\"ols-t6-visual-kicker\">Definitions<\/div>\n                <div class=\"ols-t6-visual-main\">Standard<br>Enthalpies<\/div>\n                <div class=\"ols-t6-visual-sub\">\u0394rH, \u0394fH, \u0394cH, \u0394neutH, \u0394atH<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t6-card-num\">2<\/div>\n          <\/div>\n          <div class=\"ols-t6-card-body\">\n            <p class=\"ols-t6-card-title\">Standard Enthalpy Changes<\/p>\n            <p class=\"ols-t6-card-desc\">The five standard enthalpy change definitions and how to write the equation each one refers to.<\/p>\n            <span class=\"ols-t6-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 3: Calorimetry: Measuring Enthalpy Changes -->\n        <a class=\"ols-t6-card ols-t6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/calorimetry-measuring-enthalpy-changes\/\">\n          <div class=\"ols-t6-card-img-wrap\">\n            <div class=\"ols-t6-visual ols-t6-visual--reactions\">\n              <div class=\"ols-t6-visual-panel\">\n                <div class=\"ols-t6-visual-kicker\">q = mc\u0394T<\/div>\n                <div class=\"ols-t6-visual-main\">Calorimetry<\/div>\n                <div class=\"ols-t6-visual-sub\">solutions, combustion, cooling curves<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t6-card-num\">3<\/div>\n          <\/div>\n          <div class=\"ols-t6-card-body\">\n            <p class=\"ols-t6-card-title\">Calorimetry: Measuring Enthalpy Changes<\/p>\n            <p class=\"ols-t6-card-desc\">Calculating \u0394H from a temperature change, cooling curve corrections, errors and assumptions.<\/p>\n            <span class=\"ols-t6-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 4: Hess's Law and Enthalpy Cycles -->\n        <a class=\"ols-t6-card ols-t6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/hess-law-and-enthalpy-cycles\/\">\n          <div class=\"ols-t6-card-img-wrap\">\n            <div class=\"ols-t6-visual ols-t6-visual--isomerism\">\n              <div class=\"ols-t6-visual-panel\">\n                <div class=\"ols-t6-visual-kicker\">Enthalpy cycles<\/div>\n                <div class=\"ols-t6-visual-main\">Hess&#8217;s<br>Law<\/div>\n                <div class=\"ols-t6-visual-sub\">formation and combustion routes<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t6-card-num\">4<\/div>\n          <\/div>\n          <div class=\"ols-t6-card-body\">\n            <p class=\"ols-t6-card-title\">Hess&#8217;s Law and Enthalpy Cycles<\/p>\n            <p class=\"ols-t6-card-desc\">Building enthalpy cycles and calculating \u0394H from formation and combustion data.<\/p>\n            <span class=\"ols-t6-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 5: Bond Enthalpies -->\n        <a class=\"ols-t6-card ols-t6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-6-energetics\/bond-enthalpies\/\">\n          <div class=\"ols-t6-card-img-wrap\">\n            <div class=\"ols-t6-visual ols-t6-visual--polymerisation\">\n              <div class=\"ols-t6-visual-panel\">\n                <div class=\"ols-t6-visual-kicker\">Break and make<\/div>\n                <div class=\"ols-t6-visual-main\">Bond<br>Enthalpies<\/div>\n                <div class=\"ols-t6-visual-sub\">mean values and limitations<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t6-card-num\">5<\/div>\n          <\/div>\n          <div class=\"ols-t6-card-body\">\n            <p class=\"ols-t6-card-title\">Bond Enthalpies<\/p>\n            <p class=\"ols-t6-card-desc\">Mean bond enthalpy, calculating \u0394H from bonds broken and made, and why the answers differ from Hess values.<\/p>\n            <span class=\"ols-t6-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION -->\n  <section class=\"ols-t6-spec-section\">\n    <div class=\"ols-t6-container\">\n\n      <!-- DESKTOP SPECIFICATION -->\n      <div class=\"ols-t6-spec-desktop\">\n        <div class=\"ols-t6-spec-wrap\">\n          <div class=\"ols-t6-spec-pill\">Specification Coverage<\/div>\n          <h2 class=\"ols-t6-spec-heading\">Topic 6 Energetics &#8211; Edexcel International A Level Chemistry<\/h2>\n          <p class=\"ols-t6-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 6.<\/p>\n\n          <div class=\"ols-t6-spec-rows\">\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--mid\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--mid\">6.1<\/div>\n              <div class=\"ols-t6-spec-text\">\n                <div style=\"margin:0 0 12px;\">know that:<\/div>\n                <div class=\"ols-t6-spec-sub-list\">\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">a<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">enthalpy change, \u0394H, is heat energy change measured at constant pressure<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">b<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">standard conditions are 100 kPa and a specified temperature, usually 298 K<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.2<\/div>\n              <div class=\"ols-t6-spec-text\">know that, by convention, exothermic reactions have a negative enthalpy change and endothermic reactions have a positive enthalpy change<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.3<\/div>\n              <div class=\"ols-t6-spec-text\">be able to construct and interpret enthalpy level diagrams showing an enthalpy change, including appropriate signs for exothermic and endothermic reactions<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--mid\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--mid\">6.4<\/div>\n              <div class=\"ols-t6-spec-text\">\n                <div style=\"margin:0 0 12px;\">know the following definitions of standard enthalpy change:<\/div>\n                <div class=\"ols-t6-spec-sub-list\">\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">reaction, \u0394rH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">formation, \u0394fH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">iii<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">combustion, \u0394cH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">iv<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">neutralisation, \u0394neutH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">v<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">atomisation, \u0394atH<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--mid\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--mid\">6.5<\/div>\n              <div class=\"ols-t6-spec-text\">\n                <div style=\"margin:0 0 12px;\">be able to use experimental data to calculate:<\/div>\n                <div class=\"ols-t6-spec-sub-list\">\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">energy transferred in a reaction, recalling and using energy transferred (J) = mass (g) \u00d7 specific heat capacity (J g\u207b\u00b9 \u00b0C\u207b\u00b9) \u00d7 temperature change (\u00b0C)<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">the enthalpy change of the reaction in kJ mol\u207b\u00b9, for substances mixed in an insulated container and for combustion in a suitable calorimeter<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--mid\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--mid\">6.6<\/div>\n              <div class=\"ols-t6-spec-text\">\n                <div style=\"margin:0 0 12px;\">know Hess&#8217;s Law and be able to apply it to:<\/div>\n                <div class=\"ols-t6-spec-sub-list\">\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">constructing enthalpy cycles<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-sub-row\">\n                    <div class=\"ols-t6-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t6-spec-sub-text\">calculating enthalpy changes of reaction using data provided, or data selected from a table or obtained from experiments<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.7<\/div>\n              <div class=\"ols-t6-spec-text\">Core Practical 2: determination of the enthalpy change of a reaction using Hess&#8217;s Law<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.8<\/div>\n              <div class=\"ols-t6-spec-text\">be able to evaluate results obtained from experiments and comment on sources of error, uncertainty and assumptions, including drawing suitable graphs for calorimetry and cooling curve experiments and using cooling curve corrections<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.9<\/div>\n              <div class=\"ols-t6-spec-text\">understand the terms &#8216;bond enthalpy&#8217; and &#8216;mean bond enthalpy&#8217;, use bond enthalpies to calculate enthalpy changes and understand the limitations of doing so<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.10<\/div>\n              <div class=\"ols-t6-spec-text\">be able to calculate mean bond enthalpies from enthalpy changes of reaction<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-row ols-t6-spec-row--light\">\n              <div class=\"ols-t6-spec-code ols-t6-spec-code--dark\">6.11<\/div>\n              <div class=\"ols-t6-spec-text\">understand that bond enthalpy data gives some indication about which bond will break first in a reaction, how easy or difficult it is and therefore how rapidly a reaction will take place at room temperature<\/div>\n            <\/div>\n\n          <\/div>\n        <\/div>\n      <\/div>\n\n      <!-- MOBILE SPECIFICATION -->\n      <div class=\"ols-t6-spec-mobile\">\n        <div class=\"ols-t6-spec-wrap\">\n          <div class=\"ols-t6-spec-pill\">Specification Coverage<\/div>\n          <h2 class=\"ols-t6-spec-heading\">Topic 6 Energetics &#8211; Edexcel International A Level Chemistry<\/h2>\n          <p class=\"ols-t6-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 6.<\/p>\n\n          <div class=\"ols-t6-spec-mob-rows\">\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--mid\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--mid\">6.1<\/div>\n              <div class=\"ols-t6-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">know that:<\/div>\n                <div class=\"ols-t6-spec-mob-sub-list\">\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">a<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">enthalpy change, \u0394H, is heat energy change measured at constant pressure<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">b<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">standard conditions are 100 kPa and a specified temperature, usually 298 K<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.2<\/div>\n              <div class=\"ols-t6-spec-mob-text\">know that, by convention, exothermic reactions have a negative enthalpy change and endothermic reactions have a positive enthalpy change<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.3<\/div>\n              <div class=\"ols-t6-spec-mob-text\">be able to construct and interpret enthalpy level diagrams showing an enthalpy change, including appropriate signs for exothermic and endothermic reactions<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--mid\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--mid\">6.4<\/div>\n              <div class=\"ols-t6-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">know the following definitions of standard enthalpy change:<\/div>\n                <div class=\"ols-t6-spec-mob-sub-list\">\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">reaction, \u0394rH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">formation, \u0394fH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">iii<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">combustion, \u0394cH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">iv<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">neutralisation, \u0394neutH<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">v<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">atomisation, \u0394atH<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--mid\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--mid\">6.5<\/div>\n              <div class=\"ols-t6-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">be able to use experimental data to calculate:<\/div>\n                <div class=\"ols-t6-spec-mob-sub-list\">\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">energy transferred in a reaction, recalling and using energy transferred (J) = mass (g) \u00d7 specific heat capacity (J g\u207b\u00b9 \u00b0C\u207b\u00b9) \u00d7 temperature change (\u00b0C)<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">the enthalpy change of the reaction in kJ mol\u207b\u00b9, for substances mixed in an insulated container and for combustion in a suitable calorimeter<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--mid\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--mid\">6.6<\/div>\n              <div class=\"ols-t6-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">know Hess&#8217;s Law and be able to apply it to:<\/div>\n                <div class=\"ols-t6-spec-mob-sub-list\">\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">constructing enthalpy cycles<\/div>\n                  <\/div>\n                  <div class=\"ols-t6-spec-mob-sub-row\">\n                    <div class=\"ols-t6-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t6-spec-mob-sub-text\">calculating enthalpy changes of reaction using data provided, or data selected from a table or obtained from experiments<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.7<\/div>\n              <div class=\"ols-t6-spec-mob-text\">Core Practical 2: determination of the enthalpy change of a reaction using Hess&#8217;s Law<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.8<\/div>\n              <div class=\"ols-t6-spec-mob-text\">be able to evaluate results obtained from experiments and comment on sources of error, uncertainty and assumptions, including drawing suitable graphs for calorimetry and cooling curve experiments and using cooling curve corrections<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.9<\/div>\n              <div class=\"ols-t6-spec-mob-text\">understand the terms &#8216;bond enthalpy&#8217; and &#8216;mean bond enthalpy&#8217;, use bond enthalpies to calculate enthalpy changes and understand the limitations of doing so<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.10<\/div>\n              <div class=\"ols-t6-spec-mob-text\">be able to calculate mean bond enthalpies from enthalpy changes of reaction<\/div>\n            <\/div>\n\n            <div class=\"ols-t6-spec-mob-row ols-t6-spec-mob-row--light\">\n              <div class=\"ols-t6-spec-mob-code ols-t6-spec-mob-code--dark\">6.11<\/div>\n              <div class=\"ols-t6-spec-mob-text\">understand that bond enthalpy data gives some indication about which bond will break first in a reaction, how easy or difficult it is and therefore how rapidly a reaction will take place at room temperature<\/div>\n            <\/div>\n\n          <\/div>\n        <\/div>\n      <\/div>\n\n    <\/div>\n  <\/section>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"CollectionPage\",\n      \"@id\": 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able to calculate mean bond enthalpies from enthalpy changes of reaction\",\n          \"description\": \"be able to calculate mean bond enthalpies from enthalpy changes of reaction\"\n        },\n        {\n          \"@type\": \"DefinedTerm\",\n          \"termCode\": \"6.11\",\n          \"name\": \"understand that bond enthalpy data gives some indication about which bond will break first in a reaction, how easy or difficult it is and therefore how rapidly a reaction will take place at room temperature\",\n          \"description\": \"understand that bond enthalpy data gives some indication about which bond will break first in a reaction, how easy or difficult it is and therefore how rapidly a reaction will take place at room temperature\"\n        }\n      ]\n    }\n  ]\n}\n<\/script>\n\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Revision Notes \/ A Level Chemistry \/ Edexcel International \/ Topic 6 Energetics Edexcel International A Level Chemistry Topic 6Energetics Energetics is the study of the heat energy transferred when chemicals react. This topic covers exothermic and endothermic reactions, enthalpy level diagrams, the standard enthalpy change definitions, measuring enthalpy changes by calorimetry, Hess&#8217;s law and [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":1786,"menu_order":5,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3157","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/3157","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=3157"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/3157\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/1786"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=3157"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}