{"id":4740,"date":"2026-06-02T07:46:47","date_gmt":"2026-06-02T06:46:47","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/"},"modified":"2026-10-23T14:06:30","modified_gmt":"2026-10-23T13:06:30","slug":"equations-and-reaction-types","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/","title":{"rendered":"Equations and Reaction Types"},"content":{"rendered":"\n<div class=\"ols-t5-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 5 Formulae, Equations and Amounts of Substance<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/atoms-elements-and-molecules\/\">Atoms, Elements and Molecules<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/\">Equations and Reaction Types<\/a>\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\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/writing-chemical-equations\/\">Writing Chemical Equations<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/typical-reactions-of-acids\/\">Typical Reactions of Acids<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/ionic-and-full-equations\/\">Ionic and Full Equations<\/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\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/\">Mole Calculations<\/a>\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\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/comparing-masses-of-substances\/\">Comparing Masses of Substances<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/calculations-involving-moles\/\">Calculations involving Moles<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/calculations-using-reacting-masses\/\">Calculations using Reacting Masses<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/the-yield-of-a-reaction\/\">The Yield of a Reaction<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/atom-economy\/\">Atom Economy<\/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\/topic-5-formulae-equations-and-amounts-of-substance\/empirical-and-molecular-formulae\/\">Empirical and Molecular Formulae<\/a>\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\/topic-5-formulae-equations-and-amounts-of-substance\/empirical-and-molecular-formulae\/empirical-formulae\/\">Empirical Formulae<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/empirical-and-molecular-formulae\/molecular-formulae\/\">Molecular Formulae<\/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\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/\">Calculations with Solutions and Gases<\/a>\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\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/molar-volume-calculations\/\">Molar Volume Calculations<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/concentrations-of-solutions\/\">Concentrations of Solutions<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/titration-calculations\/\">Titration Calculations<\/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\/topic-5-formulae-equations-and-amounts-of-substance\/measurement-uncertainty-and-errors\/\">Measurement Uncertainty and Errors<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/risks-hazards-and-practical-precautions\/\">Risks, Hazards and Practical Precautions<\/a>\r\n      <\/li>\r\n\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\/topic-6-organic-chemistry-i\/\">Topic 6 Organic Chemistry I<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a 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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\/\">Edexcel<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/\">Topic 5 Formulae, Equations and Amounts of Substance<\/a> \/\n        <span>Equations and Reaction Types<\/span>\n      <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t5-intro\">\n    <div class=\"ols-t5-container\">\n      <div class=\"ols-t5-intro-inner\">\n\n        <div>\n          <div class=\"ols-t5-eyebrow\">Edexcel A Level Chemistry<\/div>\n          <h1>Equations and Reaction Types<\/h1>\n          <div class=\"ols-t5-accent-bar\"><\/div>\n          <p class=\"ols-t5-intro-lead\">\n            Equations and reaction types link chemical formulae to what actually happens during a chemical change. These pages build from writing balanced chemical equations through to recognising acid reactions and writing ionic equations.\n          <\/p>\n        <\/div>\n\n        <div class=\"ols-t5-info-grid\">\n          <div class=\"ols-t5-info-card\">\n            <div class=\"ols-t5-info-card-label\">Exam Paper<\/div>\n            <div class=\"ols-t5-info-card-value\">Paper 1<\/div>\n            <div class=\"ols-t5-info-card-sub\">9CH0\/01<\/div>\n          <\/div>\n          <div class=\"ols-t5-info-card\">\n            <div class=\"ols-t5-info-card-label\">Specification Points<\/div>\n            <div class=\"ols-t5-info-card-value\">5.6 &#8211; 5.15<\/div>\n            <div class=\"ols-t5-info-card-sub\">2 points covered<\/div>\n          <\/div>\n          <div class=\"ols-t5-info-card\">\n            <div class=\"ols-t5-info-card-label\">Sub-topics<\/div>\n            <div class=\"ols-t5-info-card-value\">3 lessons<\/div>\n            <div class=\"ols-t5-info-card-sub\">Revision notes available<\/div>\n          <\/div>\n          <div class=\"ols-t5-info-card\">\n            <div class=\"ols-t5-info-card-label\">Exam Board<\/div>\n            <div class=\"ols-t5-info-card-value\">Edexcel<\/div>\n            <div class=\"ols-t5-info-card-sub\">Pearson 9CH0<\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-t5-topics\">\n    <div class=\"ols-t5-container\">\n\n      <div class=\"ols-t5-section-header\">\n        <h2 class=\"ols-t5-section-title\">Revision Notes<\/h2>\n      <\/div>\n\n      <div class=\"ols-t5-cards-grid\">\n\n        <!-- Card 1: Writing Chemical Equations -->\n        <a class=\"ols-t5-card ols-t5-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/writing-chemical-equations\/\">\n          <div class=\"ols-t5-card-img-wrap\">\n            <div class=\"ols-t5-visual ols-t5-visual--particles\">\n              <div class=\"ols-t5-visual-panel\">\n                  <div class=\"ols-t5-visual-kicker\">Balanced equations<\/div>\n                  <div class=\"ols-t5-visual-main\">Writing Chemical Equations<\/div>\n                  <div class=\"ols-t5-visual-sub\">formulae, coefficients and state symbols<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t5-card-num\">1<\/div>\n          <\/div>\n          <div class=\"ols-t5-card-body\">\n            <p class=\"ols-t5-card-title\">Writing Chemical Equations<\/p>\n            <p class=\"ols-t5-card-desc\">Revise word equations, symbol equations, balancing equations and the correct use of state symbols.<\/p>\n            <span class=\"ols-t5-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: Typical Reactions of Acids -->\n        <a class=\"ols-t5-card ols-t5-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/typical-reactions-of-acids\/\">\n          <div class=\"ols-t5-card-img-wrap\">\n            <div class=\"ols-t5-visual ols-t5-visual--equations\">\n              <div class=\"ols-t5-visual-panel\">\n                  <div class=\"ols-t5-visual-kicker\">Reaction patterns<\/div>\n                  <div class=\"ols-t5-visual-main\">Typical Reactions of Acids<\/div>\n                  <div class=\"ols-t5-visual-sub\">salts, water, hydrogen and carbon dioxide<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t5-card-num\">2<\/div>\n          <\/div>\n          <div class=\"ols-t5-card-body\">\n            <p class=\"ols-t5-card-title\">Typical Reactions of Acids<\/p>\n            <p class=\"ols-t5-card-desc\">Learn the common products formed when acids react with metals, bases, alkalis and carbonates.<\/p>\n            <span class=\"ols-t5-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: Ionic Equations -->\n        <a class=\"ols-t5-card ols-t5-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/ionic-and-full-equations\/\">\n          <div class=\"ols-t5-card-img-wrap\">\n            <div class=\"ols-t5-visual ols-t5-visual--moles\">\n              <div class=\"ols-t5-visual-panel\">\n                  <div class=\"ols-t5-visual-kicker\">Net ionic change<\/div>\n                  <div class=\"ols-t5-visual-main\">Ionic Equations<\/div>\n                  <div class=\"ols-t5-visual-sub\">reacting ions and spectator ions<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t5-card-num\">3<\/div>\n          <\/div>\n          <div class=\"ols-t5-card-body\">\n            <p class=\"ols-t5-card-title\">Ionic Equations<\/p>\n            <p class=\"ols-t5-card-desc\">Learn how ionic equations show only the reacting ions and remove spectator ions from chemical equations.<\/p>\n            <span class=\"ols-t5-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" 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class=\"ols-smap\" aria-label=\"Summary map\"><div class=\"ols-smap-head\"><h2>Summary map<\/h2><p>Download, print and revise the key facts of this topic at a glance.<\/p><\/div><div class=\"ols-smap-grid\"><article class=\"ols-smap-card\"><div class=\"ols-smap-vis\"><svg viewBox=\"0 0 120 120\" aria-hidden=\"true\"><g fill=\"none\" stroke=\"#ffffff\" stroke-width=\"2.4\" stroke-linecap=\"round\"><circle cx=\"60\" cy=\"60\" r=\"17\"\/><path d=\"M60 43V20M60 77v23M43 60H20M77 60h23M48 48 32 32M72 48l16-16M48 72 32 88M72 72l16 16\"\/><\/g><g fill=\"#ffffff\"><path d=\"M60 16l-4 7h8zM60 104l-4-7h8zM16 60l7-4v8zM104 60l-7-4v8zM29 29l2.5 7.5 5-5zM91 29l-7.5 2.5 5 5zM29 91l7.5-2.5-5-5zM91 91l-2.5-7.5-5 5z\"\/><\/g><g fill=\"#5fd0c9\"><circle cx=\"60\" cy=\"11\" r=\"3\"\/><circle cx=\"109\" cy=\"60\" r=\"3\"\/><\/g><g fill=\"#f2c14e\"><circle cx=\"11\" cy=\"60\" r=\"3\"\/><circle cx=\"96\" cy=\"96\" r=\"3\"\/><\/g><g fill=\"#9db8ff\"><circle cx=\"24\" cy=\"24\" r=\"3\"\/><circle cx=\"60\" cy=\"109\" r=\"3\"\/><\/g><\/svg><\/div><div class=\"ols-smap-body\"><span class=\"ols-smap-kicker\">Summary map \u00b7 PDF<\/span><p class=\"ols-smap-title\">Equations and Reaction Types Map<\/p><p class=\"ols-smap-board\">Edexcel A Level Chemistry \u00b7 Topic 5 Formulae, Equations and Amounts of Substance \u00b7 Equations and Reaction Types<\/p><p class=\"ols-smap-desc\">The whole section on one A4 page: balancing, state symbols, ionic equations, precipitation, displacement and the reactions of acids.<\/p><div class=\"ols-smap-row\"><a class=\"ols-smap-btn\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/ols-maps\/map-dom-5b-equations.pdf\" download rel=\"nofollow\"><svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M8 2v8M4.5 6.5 8 10l3.5-3.5M3 13h10\"\/><\/svg>Download the map<\/a><span class=\"ols-smap-meta\">6 key ideas + an equations table \u00b7 A4 portrait \u00b7 print ready<\/span><\/div><\/div><\/article><\/div><p class=\"ols-smap-note\">\u00a9 2026 Online Learning System. For personal study: printing is allowed; editing, copying and redistribution are not.<\/p><\/section>\n<!-- \/OLS-SMAP -->\n<section class=\"ols-t5-spec-section\">\n    <div class=\"ols-t5-container\">\n      <div class=\"ols-t5-spec-wrap\">\n        <div class=\"ols-t5-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-t5-spec-heading\">Equations and Reaction Types &#8211; Edexcel A Level Chemistry<\/h2>\n        <p class=\"ols-t5-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 5. Ideas from this topic are applied across quantitative chemistry, practical work and later physical, inorganic and organic topics.<\/p>\n\n        <h3 class=\"ols-t5-spec-group-title\">Equations, Reaction Types and Observations<\/h3>\n        <div class=\"ols-t5-spec-rows\">\n          <div class=\"ols-t5-spec-row\">\n            <div class=\"ols-t5-spec-code\">5.6<\/div>\n            <div class=\"ols-t5-spec-text\">be able to write balanced full and ionic equations, including state symbols, for chemical reactions<\/div>\n          <\/div>\n          <div class=\"ols-t5-spec-row ols-t5-spec-row--mid\">\n            <div class=\"ols-t5-spec-code\">5.15<\/div>\n            <div class=\"ols-t5-spec-text\">\n              be able to relate ionic and full equations, with state symbols, to observations from simple test tube reactions.\n              <div class=\"ols-t5-spec-sub-list\">\n                <div class=\"ols-t5-spec-sub-row\">\n                  <div class=\"ols-t5-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t5-spec-sub-text\">displacement reactions<\/div>\n                <\/div>\n                <div class=\"ols-t5-spec-sub-row\">\n                  <div class=\"ols-t5-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t5-spec-sub-text\">reactions of acids<\/div>\n                <\/div>\n                <div class=\"ols-t5-spec-sub-row\">\n                  <div class=\"ols-t5-spec-sub-code\">iii<\/div>\n                  <div class=\"ols-t5-spec-sub-text\">precipitation reactions<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"WebPage\",\n      \"@id\": 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These pages build from writing balanced chemical equations through to [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":4501,"menu_order":1,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-4740","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4740","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/comments?post=4740"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4740\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4501"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=4740"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}