{"id":12483,"date":"2026-10-03T08:32:45","date_gmt":"2026-10-03T07:32:45","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/"},"modified":"2026-10-03T08:35:39","modified_gmt":"2026-10-03T07:35:39","slug":"topic-13-energetics-ii","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/","title":{"rendered":"Topic 13 &#8211; Energetics II"},"content":{"rendered":"\n<div class=\"ols-t13-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 13 Energetics II<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/\">Topic 13 Energetics II Overview<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/lattice-energy-and-born-haber-cycles\/\">Lattice Energy and Born\u2013Haber Cycles<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/lattice-energy-trends-and-covalent-character\/\">Lattice Energy Trends and Covalent Character<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/enthalpy-of-solution-and-hydration\/\">Enthalpy of Solution and Hydration<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/entropy-and-the-direction-of-change\/\">Entropy and the Direction of Change<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/calculating-entropy-changes\/\">Calculating Entropy Changes<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/feasibility-gibbs-energy-and-temperature\/\">Feasibility, Gibbs Energy and Temperature<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/thermodynamic-and-kinetic-stability\/\">Thermodynamic and Kinetic Stability<\/a>\n      <\/li>\n    <\/ul>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Other Sections<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-8-energetics-i\/\">Topic 8 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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\/\">Edexcel<\/a> \/\n          <span>Topic 13 Energetics II<\/span>\n        <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t13-intro\">\n    <div class=\"ols-t13-container\">\n      <div class=\"ols-t13-intro-inner\">\n        <div>\n          <div class=\"ols-t13-eyebrow\">Edexcel A Level Chemistry<\/div>\n          <h1>Topic 13<br>Energetics II<\/h1>\n          <div class=\"ols-t13-accent-bar\"><\/div>\n          <p class=\"ols-t13-intro-lead\">Topic 13 has two parts. 13A Lattice energy covers the definitions, Born\u2013Haber cycles and their calculations, lattice energy as a measure of ionic bond strength, the perfect ionic model against experimental values, polarisation and covalent character, and enthalpies of solution and hydration with their energy cycles. 13B Entropy covers entropy and the direction of change, \u0394Ssystem, \u0394Ssurroundings and \u0394Stotal, feasibility from \u0394G = \u0394H \u2212 T\u0394Ssystem, \u0394G = \u2212RT ln K, and why a feasible reaction may still not occur.<\/p>\n        <\/div>\n        <div class=\"ols-t13-info-grid\">\n          <div class=\"ols-t13-info-card\"><div class=\"ols-t13-info-card-label\">Exam Paper<\/div><div class=\"ols-t13-info-card-value\">Paper 1<\/div><div class=\"ols-t13-info-card-sub\">9CH0\/01 (and Paper 3)<\/div><\/div>\n          <div class=\"ols-t13-info-card\"><div class=\"ols-t13-info-card-label\">Specification Points<\/div><div class=\"ols-t13-info-card-value\">13A.1 &#8211; 13B.22<\/div><div class=\"ols-t13-info-card-sub\">2 parts covered<\/div><\/div>\n          <div class=\"ols-t13-info-card\"><div class=\"ols-t13-info-card-label\">Topic Parts<\/div><div class=\"ols-t13-info-card-value\">7 pages<\/div><div class=\"ols-t13-info-card-sub\">Revision notes available<\/div><\/div>\n          <div class=\"ols-t13-info-card\"><div class=\"ols-t13-info-card-label\">Exam Board<\/div><div class=\"ols-t13-info-card-value\">Edexcel<\/div><div class=\"ols-t13-info-card-sub\">Pearson 9CH0<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-t13-topics\">\n    <div class=\"ols-t13-container\">\n\n      <div class=\"ols-t13-section-header\">\n        <h2 class=\"ols-t13-section-title\">Revision Notes<\/h2>\n      <\/div>\n\n      <div class=\"ols-t13-cards-grid\">\n\n        <!-- Card 1: w => `${lattC(w)} and Born\u2013Haber Cycles` -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/lattice-energy-and-born-haber-cycles\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--de\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">Hess\u2019s law for ionic solids<\/div>\n                <div class=\"ols-t13-visual-main\">Born\u2013Haber<br>Cycles<\/div>\n                <div class=\"ols-t13-visual-sub\">lattice energy, \u0394atH, electron affinity<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">1<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Lattice Energy and Born\u2013Haber Cycles<\/p>\n            <p class=\"ols-t13-card-desc\">Lattice energy and Born\u2013Haber cycles: definitions of atomisation, ionisation energy and electron affinity, constructing the cycle for NaCl and MgCl\u2082 and calculating the missing value.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 2: w => `${lattC(w)} Trends and Covalent Character` -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/lattice-energy-trends-and-covalent-character\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--lc\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">Charge density<\/div>\n                <div class=\"ols-t13-visual-main\">Polarisation and<br>Covalent Character<\/div>\n                <div class=\"ols-t13-visual-sub\">theoretical against experimental<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">2<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Lattice Energy Trends and Covalent Character<\/p>\n            <p class=\"ols-t13-card-desc\">Lattice energy trends: charge and radius, the perfect ionic model against Born\u2013Haber values, polarisation and covalent character in ionic compounds.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 3: Enthalpy of Solution and Hydration -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/enthalpy-of-solution-and-hydration\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--ei\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">Lattice broken, ions hydrated<\/div>\n                <div class=\"ols-t13-visual-main\">Solution and<br>Hydration<\/div>\n                <div class=\"ols-t13-visual-sub\">\u0394solH = \u2212LE + \u03a3\u0394hydH<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">3<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Enthalpy of Solution and Hydration<\/p>\n            <p class=\"ols-t13-card-desc\">Enthalpy of solution and hydration: definitions, energy cycles with lattice energy, worked calculations and the effect of ionic charge and radius.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 4: Entropy and the Direction of Change -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/entropy-and-the-direction-of-change\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--ox\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">Disorder and dispersal<\/div>\n                <div class=\"ols-t13-visual-main\">Entropy<\/div>\n                <div class=\"ols-t13-visual-sub\">S rises: solid, liquid, gas<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">4<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Entropy and the Direction of Change<\/p>\n            <p class=\"ols-t13-card-desc\">Entropy: disorder and the dispersal of energy, entropy and temperature, changes of state, dissolving, gas moles and the natural direction of change.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 5: Calculating Entropy Changes -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/calculating-entropy-changes\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--tc\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">\u03a3S(products) \u2212 \u03a3S(reactants)<\/div>\n                <div class=\"ols-t13-visual-main\">Entropy<br>Calculations<\/div>\n                <div class=\"ols-t13-visual-sub\">system, surroundings, total<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">5<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Calculating Entropy Changes<\/p>\n            <p class=\"ols-t13-card-desc\">Entropy calculations: \u0394S from standard entropies, \u0394S of the surroundings from \u2212\u0394H\/T and the total entropy change.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 6: Feasibility, Gibbs Energy and Temperature -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/feasibility-gibbs-energy-and-temperature\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--tr\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">\u0394G = \u0394H \u2212 T\u0394S<\/div>\n                <div class=\"ols-t13-visual-main\">Feasibility and<br>Temperature<\/div>\n                <div class=\"ols-t13-visual-sub\">T = \u0394H \u00f7 \u0394S<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">6<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Feasibility, Gibbs Energy and Temperature<\/p>\n            <p class=\"ols-t13-card-desc\">Feasibility: \u0394G = \u0394H \u2212 T\u0394S, the sign of \u0394G, the effect of temperature and the temperature at which a reaction becomes feasible.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 7: Thermodynamic and Kinetic Stability -->\n        <a class=\"ols-t13-card ols-t13-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-13-energetics-ii\/thermodynamic-and-kinetic-stability\/\">\n          <div class=\"ols-t13-card-img-wrap\">\n            <div class=\"ols-t13-visual ols-t13-visual--ca\">\n              <div class=\"ols-t13-visual-panel\">\n                <div class=\"ols-t13-visual-kicker\">Feasible is not fast<\/div>\n                <div class=\"ols-t13-visual-main\">Thermodynamic and<br>Kinetic Stability<\/div>\n                <div class=\"ols-t13-visual-sub\">\u0394G, E\u2090, diamond and petrol<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t13-card-num\">7<\/div>\n            <span class=\"ols-t13-card-status ols-t13-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t13-card-body\">\n            <p class=\"ols-t13-card-title\">Thermodynamic and Kinetic Stability<\/p>\n            <p class=\"ols-t13-card-desc\">Thermodynamic and kinetic stability: feasible but slow reactions, activation energy and the limits of \u0394G and \u0394Stotal predictions.<\/p>\n            <span class=\"ols-t13-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION -->\n  <section class=\"ols-t13-spec-section\">\n    <div class=\"ols-t13-container\">\n      <div class=\"ols-t13-spec-wrap\">\n        <div class=\"ols-t13-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-t13-spec-heading\">Topic 13 Energetics II &#8211; Edexcel A Level Chemistry<\/h2>\n        <p class=\"ols-t13-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate. Wording follows the Edexcel A Level Chemistry (9CH0) specification.<\/p>\n        <h3 class=\"ols-t13-spec-group-title\">13A Energetics II: Lattice energy<\/h3>\n        <div class=\"ols-t13-spec-rows\">\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13A.1<\/div><div class=\"ols-t13-spec-text\">be able to define lattice energy as the energy change when one mole of an ionic solid is formed from its gaseous ions<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13A.2<\/div><div class=\"ols-t13-spec-text\">be able to define the terms:<div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">i<\/div><div class=\"ols-t13-spec-sub-text\">enthalpy change of atomisation, \u0394atH<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">ii<\/div><div class=\"ols-t13-spec-sub-text\">electron affinity<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13A.3<\/div><div class=\"ols-t13-spec-text\">be able to construct Born-Haber cycles and carry out related calculations<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13A.4<\/div><div class=\"ols-t13-spec-text\">know that lattice energy provides a measure of ionic bond strength<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13A.5<\/div><div class=\"ols-t13-spec-text\">understand that a comparison of the experimental lattice energy value (from a Born-Haber cycle) with the theoretical value (obtained from electrostatic theory) in a particular compound indicates the degree of covalent bonding<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13A.6<\/div><div class=\"ols-t13-spec-text\">understand the meaning of polarisation as applied to ions<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13A.7<\/div><div class=\"ols-t13-spec-text\">know that the polarising power of a cation depends on its radius and charge<div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">a<\/div><div class=\"ols-t13-spec-sub-text\">know that the polarising power of a cation depends on its radius<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">b<\/div><div class=\"ols-t13-spec-sub-text\">know that the polarising power of a cation depends on its charge<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13A.8<\/div><div class=\"ols-t13-spec-text\">know that the polarisability of an anion depends on its radius and charge<div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">a<\/div><div class=\"ols-t13-spec-sub-text\">know that the polarisability of an anion depends on its radius<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">b<\/div><div class=\"ols-t13-spec-sub-text\">know that the polarisability of an anion depends on its charge<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13A.9<\/div><div class=\"ols-t13-spec-text\">be able to define the terms \u2018enthalpy change of solution, \u0394solH\u2019, and \u2018enthalpy change of hydration, \u0394hydH\u2019<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13A.10<\/div><div class=\"ols-t13-spec-text\">be able to use energy cycles and energy level diagrams to carry out calculations involving enthalpy change of solution, enthalpy change of hydration and lattice energy<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13A.11<\/div><div class=\"ols-t13-spec-text\">understand the effect of ionic charge and ionic radius on the values of:<div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">i<\/div><div class=\"ols-t13-spec-sub-text\">lattice energy<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">ii<\/div><div class=\"ols-t13-spec-sub-text\">enthalpy change of hydration<\/div><\/div><\/div><\/div><\/div>\n        <\/div>\n\n        <h3 class=\"ols-t13-spec-group-title\">13B Energetics II: Entropy<\/h3>\n        <div class=\"ols-t13-spec-rows\">\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13B.12<\/div><div class=\"ols-t13-spec-text\">understand that, since some endothermic reactions can occur at room temperature, enthalpy changes alone do not control whether reactions occur<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13B.13<\/div><div class=\"ols-t13-spec-text\"><div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">a<\/div><div class=\"ols-t13-spec-sub-text\">know that entropy is a measure of disorder of a system<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">b<\/div><div class=\"ols-t13-spec-sub-text\">know that the natural direction of change is increasing total entropy \/ positive entropy change<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13B.14<\/div><div class=\"ols-t13-spec-text\">understand why entropy changes occur during:<div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">i<\/div><div class=\"ols-t13-spec-sub-text\">changes of state<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">ii<\/div><div class=\"ols-t13-spec-sub-text\">dissolving of a solid ionic lattice<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">iii<\/div><div class=\"ols-t13-spec-sub-text\">reactions in which there is a change in the number of moles from reactants to products Students should be able to discuss typical reactions in terms of disorder and enthalpy change, including: o dissolving ammonium nitrate crystals in water o reacting ethanoic acid with ammonium carbonate o burning magnesium ribbon in air o mixing solid barium hydroxide, Ba(OH)\u2082.8H\u2082O, with solid ammonium chloride.<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13B.15<\/div><div class=\"ols-t13-spec-text\"><div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">a<\/div><div class=\"ols-t13-spec-sub-text\">understand that total entropy change is the entropy change in the system plus the entropy change in the surroundings<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">b<\/div><div class=\"ols-t13-spec-sub-text\">know the expression \u0394Stotal = \u0394Ssystem + \u0394Ssurroundings<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13B.16<\/div><div class=\"ols-t13-spec-text\">be able to calculate the entropy change for the system, \u0394Ssystem , in a reaction, given the entropies of the reactants and products<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13B.17<\/div><div class=\"ols-t13-spec-text\">be able to calculate the entropy change in the surroundings, and hence \u0394Stotal , using the expression: \u0394Ssurroundings=\u2212\u0394H\\T<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13B.18<\/div><div class=\"ols-t13-spec-text\"><div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">a<\/div><div class=\"ols-t13-spec-sub-text\">know that the balance between entropy change and enthalpy change determines feasibility<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">b<\/div><div class=\"ols-t13-spec-sub-text\">know that feasibility is represented by \u0394G = \u0394H \u2212 T\u0394Ssystem<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13B.19<\/div><div class=\"ols-t13-spec-text\">be able to use the equation \u0394G = \u0394H \u2212 T\u0394Ssystem to:<div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">i<\/div><div class=\"ols-t13-spec-sub-text\">predict whether a reaction is feasible<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">ii<\/div><div class=\"ols-t13-spec-sub-text\">determine the temperature at which a reaction is feasible<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13B.20<\/div><div class=\"ols-t13-spec-text\"><div class=\"ols-t13-spec-sub-list\"><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">a<\/div><div class=\"ols-t13-spec-sub-text\">be able to use \u0394G = \u2212RT ln K to show that feasible reactions have large equilibrium constants<\/div><\/div><div class=\"ols-t13-spec-sub-row\"><div class=\"ols-t13-spec-sub-code\">b<\/div><div class=\"ols-t13-spec-sub-text\">be able to use \u0394G = \u2212RT ln K to show that reactions with large equilibrium constants are feasible<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--light\"><div class=\"ols-t13-spec-code\">13B.21<\/div><div class=\"ols-t13-spec-text\">understand why a reaction for which the \u0394G value is negative may not occur in practice<\/div><\/div>\n          <div class=\"ols-t13-spec-row ols-t13-spec-row--mid\"><div class=\"ols-t13-spec-code ols-t13-spec-code--mid\">13B.22<\/div><div class=\"ols-t13-spec-text\">know that reactions that are thermodynamically feasible may be inhibited by kinetic factors<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": 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