{"id":3442,"date":"2026-05-13T07:38:29","date_gmt":"2026-05-13T06:38:29","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/?page_id=3442"},"modified":"2026-10-14T09:03:25","modified_gmt":"2026-10-14T08:03:25","slug":"kmno4","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/kmno4\/","title":{"rendered":"KMnO4"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-alkene-kmno4-page\">\n  <style>\n    .ols-revision-page {\n      --navy: #1C244B;\n      --blue: #2563eb;\n      --soft-blue: #eef4ff;\n      --soft-red: #fff7f7;\n      --soft-purple: #f7f0ff;\n      --soft-green: #f0f7f1;\n      --green: #3f8f46;\n      --red: #d94b2b;\n      --gold: #c9973a;\n      --grey-text: #667085;\n      --body-text: #1f2937;\n      --border: rgba(28, 36, 75, 0.14);\n      --shadow: 0 18px 45px rgba(28, 36, 75, 0.10);\n      --inner-shadow: 0 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border-radius: 22px;\n      }\n<\/style>\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 5 Alkenes<\/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\/alkene-bonding\/\">Alkene Bonding<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/geometric-isomerism\/\">Geometric Isomerism<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/electrophilic-addition-mechanism\/\">Electrophilic Addition Mechanism<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/\">Reactions of Alkenes<\/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-5-alkenes\/reactions-of-alkenes\/halogens\/\">Halogens<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/hydrogen-halide\/\">Hydrogen Halide<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/bromine-water\/\">Bromine Water<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/hydrogen\/\">Hydrogen<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/steam\/\">Steam<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/reactions-of-alkenes\/kmno4\/\">KMnO4<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/polymerisation-reactions\/\">Polymerisation Reactions<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/polymer-waste\/\">Polymer Waste<\/a>\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-6-energetics\/\">Energetics<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-7-intermolecular-forces\/\">Intermolecular Forces<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-8A-redox-chemistry\/\">Redox Chemistry<\/a>\r\n      <\/li>\r\n    <\/ul>\r\n  <\/div>\r\n<\/aside>\r\n\r\n<script>\r\n(function() 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 <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/\">Revision Notes<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/\">A Level Chemistry<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">Edexcel International<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/\">Topic 5 Alkenes<\/a> \/\n        <span>Reactions of Alkenes: KMnO<sub>4<\/sub><\/span>\n      <\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Reactions of Alkenes with KMnO<sub>4<\/sub><\/h1>\n        <p class=\"ols-page-intro\">A concise revision guide to the oxidation of alkenes using potassium manganate(VII), including the formation of diols, the purple to colourless observation and how this reaction can be used as a test for the alkene functional group.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">Exam board: Edexcel International<\/div>\n          <div class=\"ols-badge\">Topic 5: Alkenes<\/div>\n          <div class=\"ols-badge\">Reaction 6: KMnO<sub>4<\/sub><\/div>\n        <\/div>\n      <\/header>\n\n      \n<section class=\"ols-h5p-card ols-h5p-inline ols-h5p-recap\">\n<span class=\"ols-h5p-kicker\">Before you start<\/span>\n<h2>GCSE Recap: Saturated, Unsaturated and a Positive Test<\/h2>\n<p>Before you start, check the GCSE ideas this page builds on: what makes a hydrocarbon unsaturated, and what a positive test looks like.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-content\" data-content-id=\"749\"><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">1<\/div>\n          <h2>The Overall Reaction<\/h2>\n        <\/div>\n\n        <p>Alkenes react with <strong>KMnO<sub>4<\/sub><\/strong>, potassium manganate(VII), in <strong>acidified solution<\/strong> to form <strong>diols<\/strong>.<\/p>\n        <p>A <strong>diol<\/strong> is an organic compound containing two alcohol, <strong>-OH<\/strong>, groups. In this reaction, the C=C double bond opens and an <strong>-OH<\/strong> group is added to each carbon atom from the original double bond.<\/p>\n        <p>For example, <strong>propene<\/strong> is oxidised to form <strong>propane-1,2-diol<\/strong>.<\/p>\n\n        <div class=\"ols-reaction-summary\">\n          <div class=\"ols-summary-item\"><span>Functional group change<\/span><strong>Alkene \u2192 diol<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Reagent<\/span><strong>KMnO<sub>4<\/sub> in acidified solution<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Product from propene<\/span><strong>Propane-1,2-diol<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Type of reaction<\/span><strong>Oxidation<\/strong><\/div>\n        <\/div>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Key idea:<\/strong> KMnO<sub>4<\/sub> oxidises the alkene functional group, converting the C=C double bond into a diol.<\/p>\n        <\/div>\n\n        <div class=\"ols-figure-card\">\n          <div class=\"ols-figure-image\">\n            <img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-cd-09-propenediol.svg\" alt=\"Propene oxidised by cold dilute acidified manganate(VII) to propane-1,2-diol, the new OH groups highlighted\" width=\"1424\" height=\"756\">\n          <\/div>\n          <div class=\"ols-figure-caption\">\n            <p>The displayed reaction shows the alkene functional group in propene changing into a diol after oxidation with KMnO<sub>4<\/sub>.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Name the Diol<\/h2>\n<p>Apply the reaction to an alkene that this page does not use.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-48\" class=\"h5p-iframe\" data-content-id=\"48\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Alkene Oxidation MCQ: The Diol Formed from But-2-ene\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">2<\/div>\n          <h2>Conditions and Observation<\/h2>\n        <\/div>\n\n        <p>This reaction is carried out using <strong>dilute acidified KMnO<sub>4<\/sub><\/strong> at <strong>room temperature<\/strong>.<\/p>\n        <p>The important observation is that the <strong>purple colour<\/strong> of the MnO<sub>4<\/sub><sup>&#8211;<\/sup> ion <strong>decolourises to colourless<\/strong>.<\/p>\n        <p>This colour change is useful because it provides a simple chemical test for the presence of the <strong>alkene functional group<\/strong>.<\/p>\n\n        <div class=\"ols-reaction-summary\">\n          <div class=\"ols-summary-item\"><span>Condition<\/span><strong>Room temperature<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Starting colour<\/span><strong>Purple<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Final colour<\/span><strong>Colourless<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Ion responsible<\/span><strong>MnO<sub>4<\/sub><sup>&#8211;<\/sup><\/strong><\/div>\n        <\/div>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Exam focus:<\/strong> State the full observation as purple to colourless. Do not write only \u201cgoes clear\u201d.<\/p>\n        <\/div>\n      <div class=\"ols-figure-card ols-zoom-pop\">\n<div class=\"ols-figure-image\">\n<a class=\"ols-image-fullscreen-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-img-32-kmno4test.jpg\" target=\"_blank\" rel=\"noopener\" aria-label=\"Open image fullscreen\">\n<img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-img-32-kmno4test.jpg\" alt=\"Test tubes: acidified KMnO\u2084 shaken with an alkene turns purple to colourless, with an alkane it stays purple\" data-fullscreen-src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-img-32-kmno4test.jpg\">\n<\/a>\n<\/div>\n<div class=\"ols-figure-caption\"><p>Shaken with an alkene at room temperature, acidified KMnO\u2084 turns from purple to colourless as a diol forms; with an alkane it stays purple.<\/p><\/div>\n<\/div>\n<\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Two Unlabelled Bottles<\/h2>\n<p>Drag the words into place to complete the account of the two tests.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-46\" class=\"h5p-iframe\" data-content-id=\"46\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Alkene Oxidation Drag: Identifying Two Unlabelled Hydrocarbons\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">3<\/div>\n          <h2>Why It Tests for Alkenes<\/h2>\n        <\/div>\n\n        <p>The reaction can be used as a test for alkenes because alkenes contain a <strong>C=C double bond<\/strong> that can be oxidised under these conditions.<\/p>\n        <p>Alkanes do not contain a carbon-carbon double bond. They are saturated hydrocarbons, so they do not react in the same way with acidified KMnO<sub>4<\/sub> at room temperature.<\/p>\n        <p>Therefore, an alkene gives the purple to colourless change, but an alkane would show <strong>no colour change<\/strong>.<\/p>\n\n        <div class=\"ols-definition-box\">\n          <div class=\"ols-definition-circle\">Diol<\/div>\n          <p><strong>Diol:<\/strong> An organic compound containing two alcohol, <strong>-OH<\/strong>, groups. In this alkene oxidation reaction, the two -OH groups form on the two carbon atoms from the original C=C double bond.<\/p>\n        <\/div>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Remember:<\/strong> The test depends on oxidation of the alkene double bond, not substitution or hydrogenation.<\/p>\n        <\/div>\n      <div class=\"ols-figure-card ols-zoom-pop\">\n<div class=\"ols-figure-image\">\n<a class=\"ols-image-fullscreen-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-img-33-twotests.jpg\" target=\"_blank\" rel=\"noopener\" aria-label=\"Open image fullscreen\">\n<img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-img-33-twotests.jpg\" alt=\"Comparison table of bromine water and acidified KMnO\u2084 as tests for C=C: colours, reaction type, product from ethene and limits\" data-fullscreen-src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t5-img-33-twotests.jpg\">\n<\/a>\n<\/div>\n<div class=\"ols-figure-caption\"><p>Bromine water and acidified KMnO\u2084 both lose their colour with an alkene, but by addition and by oxidation respectively.<\/p><\/div>\n<\/div>\n<\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Which Samples React?<\/h2>\n<p>Click every hydrocarbon that makes the purple colour fade.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-47\" class=\"h5p-iframe\" data-content-id=\"47\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Alkene Oxidation Mark the Words: Which Samples Make the Purple Colour Fade\"><\/iframe><\/div><\/div>\n<\/section>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: The Limits of the Test<\/h2>\n<p>Write a short explanation, then compare it with the mark points and the model answer.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-49\" class=\"h5p-iframe\" data-content-id=\"49\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Alkene Oxidation Explain: What the Test Can and Cannot Tell You\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">4<\/div>\n          <h2>Common Exam Mistakes<\/h2>\n        <\/div>\n\n        <p>Students often lose marks by forgetting that the product is a <strong>diol<\/strong>, not a single alcohol.<\/p>\n        <p>Another common error is to describe the reaction as addition only. The expected reaction type here is <strong>oxidation<\/strong>.<\/p>\n        <p>For observation questions, the safest answer should include both the starting colour and the final colour.<\/p>\n\n        <div class=\"ols-reaction-summary\">\n          <div class=\"ols-summary-item\"><span>Do say<\/span><strong>Purple MnO<sub>4<\/sub><sup>&#8211;<\/sup> decolourises to colourless.<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Do not say only<\/span><strong>It goes clear.<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Product type<\/span><strong>Diol, not just alcohol.<\/strong><\/div>\n          <div class=\"ols-summary-item\"><span>Reaction type<\/span><strong>Oxidation.<\/strong><\/div>\n        <\/div>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Exam focus:<\/strong> Link the colour change to the reaction of MnO<sub>4<\/sub><sup>&#8211;<\/sup> with the alkene C=C double bond.<\/p>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Oxidising an Alkene from Start to Finish<\/h2>\n<p>Each round covers one part of the page, from the product to the conditions. Choose the one accurate statement.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-1275\" class=\"h5p-iframe\" data-content-id=\"1275\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Alkene Oxidation Summary: Pent-2-ene and Manganate(VII)\"><\/iframe><\/div><\/div>\n<\/section>\n\n      \n\n      <section class=\"ols-faq-card\">\n<h2>FAQs<\/h2>\n<p>These questions secure the conditions, product and limits of the manganate(VII) test.<\/p>\n<div class=\"ols-faq-list\">\n<div class=\"ols-faq-item\">\n<h3>Why is this reaction called oxidation?<\/h3>\n<p>In organic chemistry, gaining oxygen or losing hydrogen counts as oxidation. The alkene gains two OH groups, so it is oxidised. The manganate(VII) ions are reduced at the same time.<\/p>\n<\/div>\n<div class=\"ols-faq-item\">\n<h3>Does the KMnO<sub>4<\/sub> need to be hot or cold?<\/h3>\n<p>Cold and dilute. Hot, concentrated manganate(VII) is a much stronger oxidising agent and breaks the carbon chain at the double bond instead of stopping at the diol.<\/p>\n<\/div>\n<div class=\"ols-faq-item\">\n<h3>What forms when ethene reacts with acidified KMnO<sub>4<\/sub>?<\/h3>\n<p>Ethane-1,2-diol, HOCH<sub>2<\/sub>CH<sub>2<\/sub>OH. One OH group adds to each carbon of the original C=C bond. Ethane-1,2-diol is used as antifreeze.<\/p>\n<\/div>\n<div class=\"ols-faq-item\">\n<h3>Why does the purple colour disappear?<\/h3>\n<p>The purple colour comes from MnO<sub>4<\/sub><sup>&#8211;<\/sup> ions. As they oxidise the alkene, they are reduced to almost colourless Mn<sup>2+<\/sup> ions in the acidic solution, so the purple fades to colourless.<\/p>\n<\/div>\n<div class=\"ols-faq-item\">\n<h3>Is acidified KMnO<sub>4<\/sub> as reliable a test for alkenes as bromine water?<\/h3>\n<p>No. Acidified KMnO<sub>4<\/sub> also oxidises other compounds, such as primary and secondary alcohols and aldehydes. A colour change with it does not prove a C=C bond on its own, so bromine water is the usual test.<\/p>\n<\/div>\n<\/div>\n<\/section>\n\n      <!-- author card (moved to the end, 10 Oct 2026) -->\n      <div class=\"ols-author\">\n\n    <img decoding=\"async\"\n      class=\"ols-author-avatar-img\"\n      src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\"\n      alt=\"Dr. Mohammed Al-Fatah\"\n    >\n\n    <div class=\"ols-author-content\">\n\n      <h2 class=\"ols-author-title\">\n        Written by: Dr. Mohammed Al-Fatah\n      <\/h2>\n\n      <p class=\"ols-author-description\">\n        Chemistry specialist revision notes for A Level Chemistry.\n      <\/p>\n\n      <a\n        class=\"ols-linkedin-pill\"\n        href=\"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\"\n        target=\"_blank\"\n        rel=\"noopener noreferrer\"\n      >\n        <svg class=\"ols-linkedin-icon\" viewBox=\"0 0 24 24\" fill=\"currentColor\" aria-hidden=\"true\">\n          <path d=\"M4.98 3.5C4.98 4.88 3.86 6 2.48 6S0 4.88 0 3.5 1.12 1 2.48 1s2.5 1.12 2.5 2.5zM.5 8h4V24h-4V8zm7 0h3.8v2.2h.1c.5-.9 1.8-2.2 3.9-2.2 4.2 0 5 2.8 5 6.4V24h-4v-7.6c0-1.8 0-4.2-2.6-4.2s-3 2-3 4v7.8h-4V8z\"\/>\n        <\/svg>\n        View LinkedIn Profile\n      <\/a>\n\n    <\/div>\n\n  <\/div>\n\n\n      <section class=\"ols-related-card\">\n        <h2>Related Alkene Revision Notes<\/h2>\n        <p>Continue through Topic 5 by linking oxidation with the other addition reactions of alkenes.<\/p>\n\n        <div class=\"ols-related-grid\">\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">Steam<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">Hydrogen<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\">Bromine Water<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card ols-attr-std\" aria-label=\"Copyright notice\">\n<style id=\"ols-attribution-card-css\">.ols-attribution-card.ols-attr-std{background:linear-gradient(135deg,#ffffff,#f8fbff);border:1px solid rgba(28,36,75,0.14);border-radius:28px;box-shadow:0 18px 45px rgba(28,36,75,0.10);padding:34px;margin:24px 0;overflow:hidden;font-family:Poppins,Arial,sans-serif;box-sizing:border-box}.ols-attribution-card.ols-attr-std *{box-sizing:border-box}.ols-attribution-card.ols-attr-std p{margin:0;font-size:14px;line-height:1.65;font-weight:300;color:#667085}.ols-attribution-card.ols-attr-std strong{font-weight:700;color:#1C244B}@media (max-width:760px){.ols-attribution-card.ols-attr-std{padding:24px 18px;border-radius:22px}}<\/style>\n<p><strong>Copyright notice:<\/strong> This OLS revision content, including the explanations, layout, diagrams, tables and embedded learning structure, is authored for Online Learning System by Dr. Mohammed Al-Fatah. It may not be copied, reproduced, redistributed or adapted without written permission.<\/p>\n<\/section>\n      <\/main>\n  \n\n<script type=\"application\/ld+json\">\n{\n    \"@context\": \"https:\/\/schema.org\",\n    \"@graph\": [\n        {\n            \"@type\": \"WebPage\",\n            \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/#webpage\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/\",\n            \"name\": \"Alkene Oxidation with KMnO4 | A Level Chemistry\",\n            \"description\": \"Learn alkene oxidation with KMnO4, including diol formation, purple to colourless observation and the test for C=C double bonds.\",\n            \"inLanguage\": \"en-GB\",\n            \"isPartOf\": {\n                \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/#website\"\n            },\n            \"breadcrumb\": {\n        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