{"id":10579,"date":"2026-09-26T11:35:19","date_gmt":"2026-09-26T10:35:19","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/"},"modified":"2026-09-26T11:35:19","modified_gmt":"2026-09-26T10:35:19","slug":"topic-6-electrochemistry","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/","title":{"rendered":"Topic 6 Electrochemistry"},"content":{"rendered":"\n<div class=\"ols-cie6-page\">\n\n  <aside class=\"ols-sidebar\">\n  <div class=\"ols-sidebar-header\">\n    <h3>Revision Notes<\/h3>\n    <p>A Level Chemistry<\/p>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Topic 6 Electrochemistry<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/\">Topic Overview<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/oxidation-numbers\/\">Oxidation Numbers<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/electron-transfer-and-half-equations\/\">Electron Transfer and Half-Equations<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/disproportionation\/\">Disproportionation<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/redox-classification\/\">Redox Classification<\/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\/cie\/topic-10-group-2\/\">Topic 10 Group 2<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-11-group-17\/\">Topic 11 Group 17<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-2-atoms-molecules-and-stoichiometry\/\">Topic 2 Atoms, Molecules and Stoichiometry<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/\">Topic 9 Chemical Periodicity<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-5-chemical-energetics\/\">Topic 5 Chemical Energetics<\/a>\n      <\/li>\n    <\/ul>\n  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at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #ecfdf5 0%, #34d399 45%, #047857 100%); }\n    .ols-cie6-visual--ho { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fefce8 0%, #facc15 45%, #a16207 100%); }\n    .ols-cie6-visual--cd { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f0fdf4 0%, #86efac 45%, #166534 100%); }\n    .ols-cie6-visual--hi { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fdf4ff 0%, #d8b4fe 45%, #7e22ce 100%); }\n  <\/style>\n\n  <!-- BREADCRUMB BAR -->\n  <div class=\"ols-cie6-breadcrumb-bar\">\n    <div class=\"ols-cie6-container\">\n      <nav class=\"ols-cie6-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\/cie\/\">Cambridge International (CIE)<\/a> \/\n          <span>Topic 6 Electrochemistry<\/span>\n        <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-cie6-intro\">\n    <div class=\"ols-cie6-container\">\n      <div class=\"ols-cie6-intro-inner\">\n        <div>\n          <div class=\"ols-cie6-eyebrow\">Cambridge International AS &amp; A Level Chemistry<\/div>\n          <h1>Topic 6<br>Electrochemistry<\/h1>\n          <div class=\"ols-cie6-accent-bar\"><\/div>\n          <p class=\"ols-cie6-intro-lead\">At AS Level, Topic 6 is the redox processes of 6.1: calculating oxidation numbers, using changes in oxidation number to balance equations, the terms redox, oxidation, reduction and disproportionation in terms of electron transfer and oxidation number, oxidising and reducing agents, and Roman numerals. Electrode potentials and electrolysis (6.2 and 6.3) are A Level content and follow later. The redox classification page is revision support.<\/p>\n        <\/div>\n        <div class=\"ols-cie6-info-grid\">\n          <div class=\"ols-cie6-info-card\"><div class=\"ols-cie6-info-card-label\">Exam Papers<\/div><div class=\"ols-cie6-info-card-value\">Papers 1 &amp; 2<\/div><div class=\"ols-cie6-info-card-sub\">9701 AS Level<\/div><\/div>\n          <div class=\"ols-cie6-info-card\"><div class=\"ols-cie6-info-card-label\">Learning Outcomes<\/div><div class=\"ols-cie6-info-card-value\">6.1.1 &#8211; 6.1.5<\/div><div class=\"ols-cie6-info-card-sub\">5 outcomes at AS<\/div><\/div>\n          <div class=\"ols-cie6-info-card\"><div class=\"ols-cie6-info-card-label\">Topic Parts<\/div><div class=\"ols-cie6-info-card-value\">4 pages<\/div><div class=\"ols-cie6-info-card-sub\">Revision notes available<\/div><\/div>\n          <div class=\"ols-cie6-info-card\"><div class=\"ols-cie6-info-card-label\">Exam Board<\/div><div class=\"ols-cie6-info-card-value\">Cambridge<\/div><div class=\"ols-cie6-info-card-sub\">9701 (2025 onwards)<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-cie6-topics\">\n    <div class=\"ols-cie6-container\">\n      <div class=\"ols-cie6-section-header\">\n        <h2 class=\"ols-cie6-section-title\">Revision Notes<\/h2>\n        <p class=\"ols-cie6-section-sub\">Work through Topic 6 Electrochemistry in a structured sequence.<\/p>\n      <\/div>\n      <div class=\"ols-cie6-cards-grid\">\n\n        <!-- Card 1: Oxidation Numbers -->\n        <a class=\"ols-cie6-card ols-cie6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/oxidation-numbers\/\">\n          <div class=\"ols-cie6-card-img-wrap\">\n            <div class=\"ols-cie6-visual ols-cie6-visual--ox\">\n              <div class=\"ols-cie6-visual-panel\">\n                <div class=\"ols-cie6-visual-kicker\">Bookkeeping<\/div>\n                <div class=\"ols-cie6-visual-main\">Oxidation<br>Numbers<\/div>\n                <div class=\"ols-cie6-config-line\" aria-hidden=\"true\"><span>rules, ions, Roman numerals<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie6-card-num\">1<\/div>\n            <span class=\"ols-cie6-card-status ols-cie6-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-cie6-card-body\">\n            <p class=\"ols-cie6-card-title\">Oxidation Numbers<\/p>\n            <p class=\"ols-cie6-card-desc\">Oxidation numbers: the rules, calculating them in compounds, ions, peroxides and metal hydrides, Roman numerals and writing formulae.<\/p>\n            <span class=\"ols-cie6-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: Electron Transfer and Half-Equations -->\n        <a class=\"ols-cie6-card ols-cie6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/electron-transfer-and-half-equations\/\">\n          <div class=\"ols-cie6-card-img-wrap\">\n            <div class=\"ols-cie6-visual ols-cie6-visual--et\">\n              <div class=\"ols-cie6-visual-panel\">\n                <div class=\"ols-cie6-visual-kicker\">OIL RIG<\/div>\n                <div class=\"ols-cie6-visual-main\">Electron<br>Transfer<\/div>\n                <div class=\"ols-cie6-config-line\" aria-hidden=\"true\"><span>half-equations and agents<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie6-card-num\">2<\/div>\n            <span class=\"ols-cie6-card-status ols-cie6-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-cie6-card-body\">\n            <p class=\"ols-cie6-card-title\">Electron Transfer and Half-Equations<\/p>\n            <p class=\"ols-cie6-card-desc\">Redox as electron transfer: oxidising and reducing agents, oxidation number changes, writing ionic half-equations and combining them into full ionic equations.<\/p>\n            <span class=\"ols-cie6-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: Disproportionation -->\n        <a class=\"ols-cie6-card ols-cie6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/disproportionation\/\">\n          <div class=\"ols-cie6-card-img-wrap\">\n            <div class=\"ols-cie6-visual ols-cie6-visual--dp\">\n              <div class=\"ols-cie6-visual-panel\">\n                <div class=\"ols-cie6-visual-kicker\">Both ways at once<\/div>\n                <div class=\"ols-cie6-visual-main\">Dispropor-<br>tionation<\/div>\n                <div class=\"ols-cie6-config-line\" aria-hidden=\"true\"><span>Cl\u2082, H\u2082O\u2082, Cu\u207a<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie6-card-num\">3<\/div>\n            <span class=\"ols-cie6-card-status ols-cie6-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-cie6-card-body\">\n            <p class=\"ols-cie6-card-title\">Disproportionation<\/p>\n            <p class=\"ols-cie6-card-desc\">Disproportionation: recognising it with oxidation numbers, chlorine in water and alkali, hydrogen peroxide, copper(I) and which species cannot disproportionate.<\/p>\n            <span class=\"ols-cie6-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: Redox Classification -->\n        <a class=\"ols-cie6-card ols-cie6-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/redox-classification\/\">\n          <div class=\"ols-cie6-card-img-wrap\">\n            <div class=\"ols-cie6-visual ols-cie6-visual--rc\">\n              <div class=\"ols-cie6-visual-panel\">\n                <div class=\"ols-cie6-visual-kicker\">Redox or not?<\/div>\n                <div class=\"ols-cie6-visual-main\">Redox<br>Classification<\/div>\n                <div class=\"ols-cie6-config-line\" aria-hidden=\"true\"><span>metals, acids, unfamiliar equations<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie6-card-num\">4<\/div>\n            <span class=\"ols-cie6-card-status ols-cie6-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-cie6-card-body\">\n            <p class=\"ols-cie6-card-title\">Redox Classification<\/p>\n            <p class=\"ols-cie6-card-desc\">Classifying reactions with oxidation numbers: redox or not, s-block and p-block examples, metals with acids, and unfamiliar equations.<\/p>\n            <span class=\"ols-cie6-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-cie6-spec-section\">\n    <div class=\"ols-cie6-container\">\n      <div class=\"ols-cie6-spec-wrap\">\n        <div class=\"ols-cie6-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-cie6-spec-heading\">Topic 6 Electrochemistry &#8211; Cambridge International AS Level Chemistry<\/h2>\n        <p class=\"ols-cie6-spec-intro-text\">The following Cambridge learning outcomes state what candidates should be able to do. Wording is taken from the Cambridge International AS &amp; A Level Chemistry (9701) syllabus.<\/p>\n        <h3 class=\"ols-cie6-spec-group-title\">6.1 Redox processes: electron transfer and changes in oxidation number<\/h3>\n        <div class=\"ols-cie6-spec-rows\">\n          <div class=\"ols-cie6-spec-row ols-cie6-spec-row--light\"><div class=\"ols-cie6-spec-code\">6.1.1<\/div><div class=\"ols-cie6-spec-text\">calculate oxidation numbers of elements in compounds and ions<\/div><\/div>\n          <div class=\"ols-cie6-spec-row ols-cie6-spec-row--mid\"><div class=\"ols-cie6-spec-code ols-cie6-spec-code--mid\">6.1.2<\/div><div class=\"ols-cie6-spec-text\">use changes in oxidation numbers to help balance chemical equations<\/div><\/div>\n          <div class=\"ols-cie6-spec-row ols-cie6-spec-row--light\"><div class=\"ols-cie6-spec-code\">6.1.3<\/div><div class=\"ols-cie6-spec-text\">explain and use the terms redox, oxidation, reduction and disproportionation in terms of electron transfer and changes in oxidation number<\/div><\/div>\n          <div class=\"ols-cie6-spec-row ols-cie6-spec-row--mid\"><div class=\"ols-cie6-spec-code ols-cie6-spec-code--mid\">6.1.4<\/div><div class=\"ols-cie6-spec-text\">explain and use the terms oxidising agent and reducing agent<\/div><\/div>\n          <div class=\"ols-cie6-spec-row ols-cie6-spec-row--light\"><div class=\"ols-cie6-spec-code\">6.1.5<\/div><div class=\"ols-cie6-spec-text\">use a Roman numeral to indicate the magnitude of the oxidation number of an element<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"CollectionPage\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-6-electrochemistry\/#webpage\",\n      \"url\": 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Cambridge International AS &amp; A Level Chemistry Topic 6Electrochemistry At AS Level, Topic 6 is the redox processes of 6.1: calculating oxidation numbers, using changes in oxidation number to balance equations, the terms redox, oxidation, reduction and disproportionation in terms of 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