{"id":3504,"date":"2026-05-14T06:16:58","date_gmt":"2026-05-14T05:16:58","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/?page_id=3504"},"modified":"2026-06-28T05:54:45","modified_gmt":"2026-06-28T04:54:45","slug":"topic-4-organic-chemistry-and-alkanes","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/","title":{"rendered":"Topic 4 Organic Chemistry &amp; Alkanes"},"content":{"rendered":"\n<div class=\"ols-t4-page\">\n\n  <aside class=\"ols-sidebar\">\r\n  <div class=\"ols-sidebar-header\">\r\n    <h3>Revision Notes<\/h3>\r\n    <p>A Level Chemistry<\/p>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Topic 4 Organic Chemistry &amp; Alkanes<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/hazard-and-risk\/\">Hazard &amp; Risk<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/\">Introduction To Organic Chemistry<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/iupac-rules\/\">IUPAC Rules<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/alkene\/\">Alkene<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/alcohol\/\">Alcohol<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/halogenoalkanes\/\">Halogenoalkanes<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/aldehyde\/\">Aldehyde<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/ketone\/\">Ketone<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/carboxylic-acid\/\">Carboxylic Acid<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/organic-chemistry\/ester\/\">Ester<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/isomerism\/\">Isomerism<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/crude-oil\/\">Alkanes from Crude Oil<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/crude-oil\/fractional-distillation\/\">Fractional Distillation<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/crude-oil\/cracking\/\">Cracking<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/crude-oil\/reforming\/\">Reforming<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/fuel\/\">Alkanes as Fuel<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/fuel\/combustion\/\">Combustion<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/fuel\/oxides-of-sulfur\/\">Oxides of Sulfur<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/fuel\/oxides-of-nitrogen\/\">Oxides of Nitrogen<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/fuel\/catalytic-converter\/\">Catalytic Converter<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/alternative-fuel\/\">Alternative Fuel<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/reactions\/\">Reactions of Alkanes<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/reactions\/free-radical-substitution\/\">Free Radical Substitution<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/reactions\/initiation\/\">Initiation<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/reactions\/propagation\/\">Propagation<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/reactions\/termination\/\">Termination<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/reactions\/further-substitution\/\">Further Substitution<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n    <\/ul>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Next Topics<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/\">Alkenes<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a 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=========================================================\n       RESPONSIVE\n    ========================================================= *\/\n\n    @media (max-width: 1024px) {\n      .ols-t4-cards-grid {\n        grid-template-columns: repeat(2, minmax(0, 1fr));\n      }\n    }\n\n    @media (max-width: 860px) {\n      .ols-t4-intro-inner {\n        grid-template-columns: 1fr;\n        gap: 40px;\n      }\n    }\n\n    @media (max-width: 640px) {\n      .ols-t4-intro {\n        padding: 24px 0 52px;\n      }\n\n      .ols-t4-topics {\n        padding: 52px 0 58px;\n      }\n\n      .ols-t4-cards-grid {\n        grid-template-columns: 1fr;\n        gap: 14px;\n      }\n\n      .ols-t4-spec-section {\n        padding: 52px 0 64px;\n      }\n\n      .ols-t4-spec-wrap {\n        padding: 24px 18px;\n        border-radius: 20px;\n      }\n\n      .ols-t4-info-grid {\n        grid-template-columns: 1fr 1fr;\n      }\n    }\n\n  <\/style>\n\n  <!-- BREADCRUMB BAR - sits above everything -->\n  <div class=\"ols-t4-breadcrumb-bar\">\n    <div class=\"ols-t4-container\">\n      <nav class=\"ols-t4-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 4 Organic Chemistry and Alkanes<\/span>\n      <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t4-intro\">\n    <div class=\"ols-t4-container\">\n      <div class=\"ols-t4-intro-inner\">\n\n        <div>\n          <div class=\"ols-t4-eyebrow\">Edexcel International A Level Chemistry<\/div>\n          <h1>Topic 4<br>Organic Chemistry<br>&amp; Alkanes<\/h1>\n          <div class=\"ols-t4-accent-bar\"><\/div>\n          <p class=\"ols-t4-intro-lead\">\n            Topic 4 introduces the foundations of organic chemistry before applying them to alkanes. This topic covers hazard and risk, functional groups, homologous series, IUPAC naming, structural isomerism, crude oil, alkane combustion, alternative fuels and free radical substitution.\n          <\/p>\n        <\/div>\n\n        <div class=\"ols-t4-info-grid\">\n          <div class=\"ols-t4-info-card\">\n            <div class=\"ols-t4-info-card-label\">Exam Unit<\/div>\n            <div class=\"ols-t4-info-card-value\">Unit 1<\/div>\n            <div class=\"ols-t4-info-card-sub\">WCH11\/01 &#8211; IAS<\/div>\n          <\/div>\n          <div class=\"ols-t4-info-card\">\n            <div class=\"ols-t4-info-card-label\">Specification Points<\/div>\n            <div class=\"ols-t4-info-card-value\">4.1 &#8211; 4.18<\/div>\n            <div class=\"ols-t4-info-card-sub\">18 points covered<\/div>\n          <\/div>\n          <div class=\"ols-t4-info-card\">\n            <div class=\"ols-t4-info-card-label\">Sub-topics<\/div>\n            <div class=\"ols-t4-info-card-value\">7 lessons<\/div>\n            <div class=\"ols-t4-info-card-sub\">Revision notes available<\/div>\n          <\/div>\n          <div class=\"ols-t4-info-card\">\n            <div class=\"ols-t4-info-card-label\">Exam Board<\/div>\n            <div class=\"ols-t4-info-card-value\">Edexcel IAL<\/div>\n            <div class=\"ols-t4-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-t4-topics\">\n    <div class=\"ols-t4-container\">\n\n      <div class=\"ols-t4-section-header\">\n        <h2 class=\"ols-t4-section-title\">Revision Notes<\/h2>\n      <\/div>\n\n      <div class=\"ols-t4-cards-grid\">\n\n        <!-- Card 1: Hazard & Risk -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/hazard-and-risk\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--hazard\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">Safety first<\/div>\n                <div class=\"ols-t4-visual-main\">Hazard<br>&amp; Risk<\/div>\n                <div class=\"ols-t4-visual-sub\">scale, precautions and safer methods<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">1<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Hazard &amp; Risk<\/p>\n            <p class=\"ols-t4-card-desc\">The difference between hazard and risk, why risk assessment matters, and how to reduce risk in organic practical work.<\/p>\n            <span class=\"ols-t4-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: Introduction to Organic Chemistry -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--organic\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">Functional groups<\/div>\n                <div class=\"ols-t4-visual-main\">Organic<br>Families<\/div>\n                <div class=\"ols-t4-molecule-row\" aria-hidden=\"true\">\n                  <span class=\"ols-t4-atom\"><\/span>\n                  <span class=\"ols-t4-bond\"><\/span>\n                  <span class=\"ols-t4-atom\"><\/span>\n                  <span class=\"ols-t4-bond\"><\/span>\n                  <span class=\"ols-t4-atom\"><\/span>\n                <\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">2<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Introduction to Organic Chemistry<\/p>\n            <p class=\"ols-t4-card-desc\">Homologous series, functional groups, organic reaction classes, bond fission, free radicals and electrophiles.<\/p>\n            <span class=\"ols-t4-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: Isomerism -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/isomerism\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--isomerism\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">Same formula<\/div>\n                <div class=\"ols-t4-visual-main\">Different<br>Structures<\/div>\n                <div class=\"ols-t4-visual-sub\">structural isomers of organic molecules<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">3<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Isomerism<\/p>\n            <p class=\"ols-t4-card-desc\">Structural isomerism, molecular formulae, displayed formulae and drawing different organic structures correctly.<\/p>\n            <span class=\"ols-t4-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: Alkanes from Crude Oil -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--crude\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">Crude oil<\/div>\n                <div class=\"ols-t4-visual-main\">Fractions<br>&amp; Cracking<\/div>\n                <div class=\"ols-t4-visual-sub\">distillation, cracking and reforming<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">4<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Alkanes from Crude Oil<\/p>\n            <p class=\"ols-t4-card-desc\">How alkanes are obtained from crude oil through fractional distillation, cracking and reforming reactions.<\/p>\n            <span class=\"ols-t4-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: Alkanes as Fuel -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--fuel\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-flame\" aria-hidden=\"true\"><\/div>\n                <div class=\"ols-t4-visual-main\">Combustion<\/div>\n                <div class=\"ols-t4-visual-sub\">fuels, pollutants and acidic oxides<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">5<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Alkanes as Fuel<\/p>\n            <p class=\"ols-t4-card-desc\">Combustion equations, carbon monoxide, oxides of nitrogen and sulfur, particulates and unburned hydrocarbons.<\/p>\n            <span class=\"ols-t4-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 6: Alternative Fuel -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/alternative-fuel\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--alternative\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-droplet\" aria-hidden=\"true\"><\/div>\n                <div class=\"ols-t4-visual-main\">Carbon<br>Neutrality<\/div>\n                <div class=\"ols-t4-visual-sub\">petrol, bioethanol and hydrogen<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">6<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Alternative Fuel<\/p>\n            <p class=\"ols-t4-card-desc\">Sustainability, reducing emissions, carbon neutrality and comparisons between petrol, bioethanol and hydrogen.<\/p>\n            <span class=\"ols-t4-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 7: Reactions of Alkanes -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--radical\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-radical-dot\" aria-hidden=\"true\"><\/div>\n                <div class=\"ols-t4-visual-main\">Free Radical<br>Substitution<\/div>\n                <div class=\"ols-t4-visual-sub\">initiation, propagation and termination<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">7<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Reactions of Alkanes<\/p>\n            <p class=\"ols-t4-card-desc\">Alkane reactions with oxygen and halogens, including the mechanism of free radical substitution.<\/p>\n            <span class=\"ols-t4-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      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION -->\n  <section class=\"ols-t4-spec-section\">\n    <div class=\"ols-t4-container\">\n\n      <!-- DESKTOP SPECIFICATION -->\n      <div class=\"ols-t4-spec-desktop\">\n        <div class=\"ols-t4-spec-wrap\">\n          <div class=\"ols-t4-spec-pill\">Specification Coverage<\/div>\n          <h2 class=\"ols-t4-spec-heading\">Topic 4 Organic Chemistry &amp; Alkanes &#8211; Edexcel International A Level Chemistry<\/h2>\n          <p class=\"ols-t4-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 4.<\/p>\n\n          <h3 class=\"ols-t4-spec-group-title\">4A: Introduction<\/h3>\n          <div class=\"ols-t4-spec-rows\">\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.1<\/div>\n              <div class=\"ols-t4-spec-text\">understand the difference between hazard and risk<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.2<\/div>\n              <div class=\"ols-t4-spec-text\">understand the hazards associated with organic compounds and why it is necessary to carry out risk assessments when dealing with potentially hazardous materials<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.3<\/div>\n              <div class=\"ols-t4-spec-text\">\n                <div style=\"margin:0 0 12px;\">be able to suggest ways in which risks can be reduced and reactions carried out safely, for example:<\/div>\n                <div class=\"ols-t4-spec-sub-list\">\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">working on a smaller scale<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">taking precautions specific to the hazard<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">iii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">using an alternative method that involves less hazardous substances<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.4<\/div>\n              <div class=\"ols-t4-spec-text\">understand the concepts of homologous series and functional group<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.5<\/div>\n              <div class=\"ols-t4-spec-text\">\n                <div style=\"margin:0 0 12px;\">be able to apply the rules of International Union of Pure and Applied Chemistry (IUPAC) nomenclature to:<\/div>\n                <div class=\"ols-t4-spec-sub-list\">\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">name compounds relevant to this specification<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">draw these compounds, as they are encountered in the specification, using structural, displayed and skeletal formulae<\/div>\n                  <\/div>\n                <\/div>\n                <div class=\"ols-t4-spec-note\">Students will be expected to know prefixes for compounds up to C<sub>10<\/sub>.<\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.6<\/div>\n              <div class=\"ols-t4-spec-text\">be able to classify reactions as addition, substitution, oxidation, reduction or polymerisation<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.7<\/div>\n              <div class=\"ols-t4-spec-text\">\n                <div style=\"margin:0 0 12px;\">understand that bond breaking can be:<\/div>\n                <div class=\"ols-t4-spec-sub-list\">\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">homolytic, to produce free radicals<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">heterolytic, to produce ions<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.8<\/div>\n              <div class=\"ols-t4-spec-text\">know definitions of the terms free radical and electrophile<\/div>\n            <\/div>\n\n          <\/div>\n\n          <h3 class=\"ols-t4-spec-group-title\">4B: Alkanes<\/h3>\n          <div class=\"ols-t4-spec-rows\">\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.9<\/div>\n              <div class=\"ols-t4-spec-text\">know the general formula of alkanes and cycloalkanes, and understand that they are hydrocarbons containing carbon and hydrogen only which are saturated and contain single bonds only<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.10<\/div>\n              <div class=\"ols-t4-spec-text\">understand the term structural isomerism and be able to draw the structural isomers of organic molecules, given their molecular formula<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.11<\/div>\n              <div class=\"ols-t4-spec-text\">be able to draw and name the structural isomers of alkanes and cycloalkanes with up to six carbon atoms<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.12<\/div>\n              <div class=\"ols-t4-spec-text\">know that alkanes are used as fuels and obtained from the fractional distillation, cracking and reforming of crude oil, and be able to write equations for these reactions<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.13<\/div>\n              <div class=\"ols-t4-spec-text\">know that pollutants, including carbon monoxide, oxides of nitrogen and sulfur, carbon particulates and unburned hydrocarbons, are emitted during the combustion of alkane fuels<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.14<\/div>\n              <div class=\"ols-t4-spec-text\">understand the problems arising from pollutants from the combustion of alkane fuels, limited to the toxicity of carbon monoxide and why it is toxic, and the acidity of oxides of nitrogen and sulfur<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.15<\/div>\n              <div class=\"ols-t4-spec-text\">be able to discuss the reasons for developing alternative fuels in terms of sustainability and reducing emissions, including the emission of CO<sub>2<\/sub> and its relationship to climate change<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.16<\/div>\n              <div class=\"ols-t4-spec-text\">be able to apply the concept of carbon neutrality to different fuels, such as petrol, bioethanol and hydrogen<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.17<\/div>\n              <div class=\"ols-t4-spec-text\">\n                <div style=\"margin:0 0 12px;\">understand the reactions of alkanes with:<\/div>\n                <div class=\"ols-t4-spec-sub-list\">\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">oxygen in the air, combustion<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">halogens<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.18<\/div>\n              <div class=\"ols-t4-spec-text\">\n                <div style=\"margin:0 0 12px;\">understand the mechanism of the free radical substitution reaction between an alkane and a halogen:<\/div>\n                <div class=\"ols-t4-spec-sub-list\">\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">using free radicals, which are species with an unpaired electron, represented by a single dot<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">showing the initiation step of the mechanism, with curly half-arrows for free radical formation<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">iii<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">showing the propagation and termination steps of the mechanism<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-sub-row\">\n                    <div class=\"ols-t4-spec-sub-code\">iv<\/div>\n                    <div class=\"ols-t4-spec-sub-text\">having limited use in synthesis because of further substitution reactions<\/div>\n                  <\/div>\n                <\/div>\n                <div class=\"ols-t4-spec-note\">Further suggested practical: Cracking alkanes by thermal decomposition, including liquid paraffin using aluminium oxide as a catalyst.<\/div>\n              <\/div>\n            <\/div>\n\n          <\/div>\n        <\/div>\n      <\/div>\n\n      <!-- MOBILE SPECIFICATION -->\n      <div class=\"ols-t4-spec-mobile\">\n        <div class=\"ols-t4-spec-wrap\">\n          <div class=\"ols-t4-spec-pill\">Specification Coverage<\/div>\n          <h2 class=\"ols-t4-spec-heading\">Topic 4 Organic Chemistry &amp; Alkanes &#8211; Edexcel International A Level Chemistry<\/h2>\n          <p class=\"ols-t4-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 4.<\/p>\n\n          <h3 class=\"ols-t4-spec-group-title\">4A: Introduction<\/h3>\n          <div class=\"ols-t4-spec-mob-rows\">\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.1<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand the difference between hazard and risk<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.2<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand the hazards associated with organic compounds and why it is necessary to carry out risk assessments when dealing with potentially hazardous materials<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.3<\/div>\n              <div class=\"ols-t4-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">be able to suggest ways in which risks can be reduced and reactions carried out safely, for example:<\/div>\n                <div class=\"ols-t4-spec-mob-sub-list\">\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">working on a smaller scale<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">taking precautions specific to the hazard<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">iii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">using an alternative method that involves less hazardous substances<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.4<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand the concepts of homologous series and functional group<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.5<\/div>\n              <div class=\"ols-t4-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">be able to apply IUPAC nomenclature to:<\/div>\n                <div class=\"ols-t4-spec-mob-sub-list\">\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">name compounds relevant to this specification<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">draw these compounds using structural, displayed and skeletal formulae<\/div>\n                  <\/div>\n                <\/div>\n                <div class=\"ols-t4-spec-note\" style=\"margin-top:10px;\">Students will be expected to know prefixes for compounds up to C<sub>10<\/sub>.<\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.6<\/div>\n              <div class=\"ols-t4-spec-mob-text\">be able to classify reactions as addition, substitution, oxidation, reduction or polymerisation<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.7<\/div>\n              <div class=\"ols-t4-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">understand that bond breaking can be:<\/div>\n                <div class=\"ols-t4-spec-mob-sub-list\">\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">homolytic, to produce free radicals<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">heterolytic, to produce ions<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.8<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know definitions of the terms free radical and electrophile<\/div>\n            <\/div>\n\n          <\/div>\n\n          <h3 class=\"ols-t4-spec-group-title\">4B: Alkanes<\/h3>\n          <div class=\"ols-t4-spec-mob-rows\">\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.9<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know the general formula of alkanes and cycloalkanes, and understand that they are saturated hydrocarbons containing single bonds only<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.10<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand structural isomerism and be able to draw structural isomers from a molecular formula<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.11<\/div>\n              <div class=\"ols-t4-spec-mob-text\">be able to draw and name structural isomers of alkanes and cycloalkanes with up to six carbon atoms<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.12<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know that alkanes are used as fuels and obtained from fractional distillation, cracking and reforming of crude oil<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.13<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know that pollutants are emitted during combustion of alkane fuels, including carbon monoxide, oxides of nitrogen and sulfur, carbon particulates and unburned hydrocarbons<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.14<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand problems caused by alkane combustion pollutants, including carbon monoxide toxicity and the acidity of oxides of nitrogen and sulfur<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.15<\/div>\n              <div class=\"ols-t4-spec-mob-text\">be able to discuss reasons for developing alternative fuels in terms of sustainability, reducing emissions, CO<sub>2<\/sub> and climate change<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.16<\/div>\n              <div class=\"ols-t4-spec-mob-text\">be able to apply carbon neutrality to fuels such as petrol, bioethanol and hydrogen<\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.17<\/div>\n              <div class=\"ols-t4-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">understand the reactions of alkanes with:<\/div>\n                <div class=\"ols-t4-spec-mob-sub-list\">\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">oxygen in the air, combustion<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">halogens<\/div>\n                  <\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n\n            <div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.18<\/div>\n              <div class=\"ols-t4-spec-mob-text\">\n                <div style=\"margin:0 0 10px;\">understand free radical substitution between an alkane and a halogen:<\/div>\n                <div class=\"ols-t4-spec-mob-sub-list\">\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">i<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">using free radicals represented by a single dot<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">ii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">showing initiation with curly half-arrows<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">iii<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">showing propagation and termination steps<\/div>\n                  <\/div>\n                  <div class=\"ols-t4-spec-mob-sub-row\">\n                    <div class=\"ols-t4-spec-mob-sub-code\">iv<\/div>\n                    <div class=\"ols-t4-spec-mob-sub-text\">recognising limited synthetic use because of further substitution<\/div>\n                  <\/div>\n                <\/div>\n                <div class=\"ols-t4-spec-note\" style=\"margin-top:10px;\">Further suggested practical: Cracking alkanes by thermal decomposition using aluminium oxide as a catalyst.<\/div>\n              <\/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\": \"Organization\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/#organization\",\n      \"name\": \"Online Learning System\",\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/\",\n      \"logo\": {\n        \"@type\": \"ImageObject\",\n        \"url\": 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