{"id":4689,"date":"2026-06-01T12:06:12","date_gmt":"2026-06-01T11:06:12","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/ionic-and-full-equations\/"},"modified":"2026-06-28T05:51:25","modified_gmt":"2026-06-28T04:51:25","slug":"ionic-and-full-equations","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\/ionic-and-full-equations\/","title":{"rendered":"Ionic and Full Equations"},"content":{"rendered":"\n<!--\n===============================================================================\nONLINE LEARNING SYSTEM COPYRIGHT NOTICE\n\u00a9 Online Learning System. 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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 href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-7-modern-analytical-techniques-i\/\">Topic 7 Modern Analytical Techniques I<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\">Topic 4 Inorganic Chemistry &amp; The Periodic Table<\/a>\r\n      <\/li>\r\n    <\/ul>\r\n  <\/div>\r\n<\/aside>\r\n\r\n<script>\r\n(function() {\r\n  function normalisePath(path) {\r\n    return String(path || '')\r\n      .split('?')[0]\r\n      .split('#')[0]\r\n      .replace(\/\\\/+$\/, '')\r\n      .toLowerCase();\r\n  }\r\n\r\n  function highlightActive() {\r\n    var sidebar = document.querySelector('.ols-sidebar');\r\n    if (!sidebar) return false;\r\n\r\n    var currentPath = normalisePath(window.location.pathname);\r\n    var links = sidebar.querySelectorAll('a[href]');\r\n    var matched = null;\r\n   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Formulae, Equations and Amounts of Substance<\/a> \/\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> \/\n        <span>Ionic Equations<\/span>\n      <\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Ionic Equations<\/h1>\n        <p class=\"ols-page-intro\">A focused revision guide to ionic equations, spectator ions and precipitation reactions. Ionic equations look difficult at first, but they often make reactions easier because they show only the particles that actually change.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">Unit: Paper 1<\/div>\n          <div class=\"ols-badge\">Topic 5: Formulae, Equations and Amounts of Substance<\/div>\n          <div class=\"ols-badge\">9CH0\/01<\/div>\n        <\/div>\n\n        <div class=\"ols-author\">\n          <img decoding=\"async\" class=\"ols-author-avatar-img\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\" alt=\"Dr. Mohammed Al-Fatah\">\n          <div class=\"ols-author-content\">\n            <h2 class=\"ols-author-title\">Written by:<br><span>Dr. Mohammed Al-Fatah<\/span><\/h2>\n            <p class=\"ols-author-description\">Chemistry specialist revision notes for A Level Chemistry.<\/p>\n            <a class=\"ols-linkedin-pill\" href=\"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\" target=\"_blank\" rel=\"noopener noreferrer\">\n              <svg class=\"ols-linkedin-icon\" viewBox=\"0 0 24 24\" fill=\"currentColor\" aria-hidden=\"true\"><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\"><\/path><\/svg>\n              View LinkedIn Profile\n            <\/a>\n          <\/div>\n        <\/div>\n      <\/header>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">1<\/div><h2>Why Ionic Equations Are Useful<\/h2><\/div>\n        <p>An <strong>ionic equation<\/strong> shows the ions and particles that actually take part in a reaction. It leaves out ions that remain unchanged in solution.<\/p>\n        <p>This is why ionic equations are often shorter than full chemical equations. They remove the chemical detail that is present in the mixture but not directly involved in the reaction.<\/p>\n        <div class=\"ols-definition-box\"><p><strong>Ionic equation:<\/strong> an equation that represents a reaction using the reacting ions or particles, with spectator ions removed.<\/p><\/div>\n        <div class=\"ols-key-box\"><p><strong>Key idea:<\/strong> full equations show every formula in the reaction mixture, while ionic equations show the actual chemical change.<\/p><\/div>\n      <\/article>\n\n      <div class=\"ols-zoom-card\">\n        <div class=\"ols-zoom-card-image\">\n          <img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Understanding-ionic-equations-in-chemistry.webp\" alt=\"Understanding ionic equations in chemistry with reacting ions and spectator ions\" class=\"ols-zoomable-img ols-lightbox-target\" draggable=\"false\">\n        <\/div>\n        <div class=\"ols-zoom-card-caption\">\n          <p>Ionic equations focus attention on the particles that react, rather than every ion present in the solution.<\/p>\n        <\/div>\n      <\/div>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">2<\/div><h2>Ions in Aqueous Solution<\/h2><\/div>\n        <p>When a soluble ionic compound dissolves in water, its ions separate and move around in solution. For example, sodium chloride solution contains <strong>Na<sup>+<\/sup>(aq)<\/strong> ions and <strong>Cl<sup>&#8211;<\/sup>(aq)<\/strong> ions.<\/p>\n        <p>The state symbol <strong>(aq)<\/strong> means <strong>aqueous<\/strong>, which means dissolved in water. It is important because ionic equations often involve dissolved ions.<\/p>\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>State symbol<\/th>\n                <th>Meaning<\/th>\n                <th>Use in ionic equations<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"State symbol\">(s)<\/td>\n                <td data-label=\"Meaning\">Solid<\/td>\n                <td data-label=\"Use in ionic equations\">Used for precipitates and insoluble substances.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"State symbol\">(l)<\/td>\n                <td data-label=\"Meaning\">Liquid<\/td>\n                <td data-label=\"Use in ionic equations\">Used for pure liquids, such as water.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"State symbol\">(g)<\/td>\n                <td data-label=\"Meaning\">Gas<\/td>\n                <td data-label=\"Use in ionic equations\">Used when a gaseous product forms.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"State symbol\">(aq)<\/td>\n                <td data-label=\"Meaning\">Aqueous solution<\/td>\n                <td data-label=\"Use in ionic equations\">Used for ions dissolved in water.<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n        <div class=\"ols-key-box\"><p><strong>Exam focus:<\/strong> state symbols should be included in ionic equations when requested, especially for precipitates and aqueous ions.<\/p><\/div>\n      <\/article>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">3<\/div><h2>Spectator Ions<\/h2><\/div>\n        <p>A <strong>spectator ion<\/strong> is an ion that is present in the reaction mixture but does not change during the reaction. It appears unchanged on both sides of the full ionic equation.<\/p>\n        <p>For example, in the reaction between sodium chloride solution and silver nitrate solution, sodium ions and nitrate ions remain dissolved in solution. They do not form the precipitate.<\/p>\n        <div class=\"ols-definition-box\"><p><strong>Spectator ion:<\/strong> an ion that is present during a reaction but is not chemically changed.<\/p><\/div>\n        <div class=\"ols-key-box\"><p><strong>How to spot one:<\/strong> if the same ion appears with the same charge and state symbol on both sides of the equation, it can be cancelled.<\/p><\/div>\n      <\/article>\n\n      <article class=\"ols-note-card orange\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">4<\/div><h2>Precipitation Reactions<\/h2><\/div>\n        <p>A <strong>precipitation reaction<\/strong> occurs when two solutions are mixed and an insoluble solid forms. The solid product is called a <strong>precipitate<\/strong>.<\/p>\n        <p>Precipitation reactions are a common context for ionic equations because the useful equation often shows only the two ions that join together to form the insoluble solid.<\/p>\n        <div class=\"ols-definition-box\"><p><strong>Precipitate:<\/strong> an insoluble solid formed when two solutions react.<\/p><\/div>\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Reaction mixture<\/th>\n                <th>Observation<\/th>\n                <th>Ionic change<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Reaction mixture\">Sodium chloride solution and silver nitrate solution<\/td>\n                <td data-label=\"Observation\">A white precipitate forms.<\/td>\n                <td data-label=\"Ionic change\">Ag<sup>+<\/sup>(aq) and Cl<sup>&#8211;<\/sup>(aq) form AgCl(s).<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Reaction mixture\">Barium chloride solution and sulfate ions<\/td>\n                <td data-label=\"Observation\">A white precipitate forms.<\/td>\n                <td data-label=\"Ionic change\">Ba<sup>2+<\/sup>(aq) and SO<sub>4<\/sub><sup>2-<\/sup>(aq) form BaSO<sub>4<\/sub>(s).<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <\/article>\n\n      <div class=\"ols-zoom-card\">\n        <div class=\"ols-zoom-card-image\">\n          <img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/precipitation-reaction.webp\" alt=\"Precipitation reaction showing ions joining to form an insoluble solid\" class=\"ols-zoomable-img ols-lightbox-target\" draggable=\"false\">\n        <\/div>\n        <div class=\"ols-zoom-card-caption\">\n          <p>A precipitate forms when ions in solution are strongly attracted and produce an insoluble solid.<\/p>\n        <\/div>\n      <\/div>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">5<\/div><h2>Example: Silver Chloride Precipitation<\/h2><\/div>\n        <p>When sodium chloride solution is mixed with silver nitrate solution, a white precipitate of <strong>silver chloride<\/strong> forms.<\/p>\n        <div class=\"ols-definition-box\"><p><strong>Full equation:<\/strong> NaCl(aq) + AgNO<sub>3<\/sub>(aq) \u2192 AgCl(s) + NaNO<sub>3<\/sub>(aq)<\/p><\/div>\n        <p>In solution, the dissolved ionic compounds can be shown as ions:<\/p>\n        <div class=\"ols-definition-box\"><p>Na<sup>+<\/sup>(aq) + Cl<sup>&#8211;<\/sup>(aq) + Ag<sup>+<\/sup>(aq) + NO<sub>3<\/sub><sup>&#8211;<\/sup>(aq) \u2192 AgCl(s) + Na<sup>+<\/sup>(aq) + NO<sub>3<\/sub><sup>&#8211;<\/sup>(aq)<\/p><\/div>\n        <p>The <strong>Na<sup>+<\/sup><\/strong> and <strong>NO<sub>3<\/sub><sup>&#8211;<\/sup><\/strong> ions are spectator ions. Once they are removed, the ionic equation is:<\/p>\n        <div class=\"ols-key-box\"><p><strong>Ionic equation:<\/strong> Ag<sup>+<\/sup>(aq) + Cl<sup>&#8211;<\/sup>(aq) \u2192 AgCl(s)<\/p><\/div>\n      <\/article>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">6<\/div><h2>How to Write Ionic Equations<\/h2><\/div>\n        <p>Start with the balanced full equation, then separate aqueous ionic substances into ions. Substances with state symbols <strong>(s)<\/strong>, <strong>(l)<\/strong> and <strong>(g)<\/strong> normally stay together.<\/p>\n        <ol>\n          <li>Write a correct balanced full equation.<\/li>\n          <li>Split aqueous ionic substances into their ions.<\/li>\n          <li>Keep solids, liquids, gases and covalent molecules together.<\/li>\n          <li>Cancel spectator ions that appear unchanged on both sides.<\/li>\n          <li>Check that atoms and charges are balanced.<\/li>\n        <\/ol>\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Substance type<\/th>\n                <th>What to do<\/th>\n                <th>Example<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Substance type\">Aqueous ionic compound<\/td>\n                <td data-label=\"What to do\">Split into ions.<\/td>\n                <td data-label=\"Example\">NaCl(aq) becomes Na<sup>+<\/sup>(aq) + Cl<sup>&#8211;<\/sup>(aq)<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Substance type\">Solid precipitate<\/td>\n                <td data-label=\"What to do\">Keep as a formula.<\/td>\n                <td data-label=\"Example\">AgCl(s) stays as AgCl(s)<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Substance type\">Liquid water<\/td>\n                <td data-label=\"What to do\">Keep as a molecule.<\/td>\n                <td data-label=\"Example\">H<sub>2<\/sub>O(l) stays as H<sub>2<\/sub>O(l)<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Substance type\">Gas<\/td>\n                <td data-label=\"What to do\">Keep as a formula.<\/td>\n                <td data-label=\"Example\">H<sub>2<\/sub>(g) stays as H<sub>2<\/sub>(g)<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <\/article>\n\n      <article class=\"ols-note-card orange\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">7<\/div><h2>Example: Barium Sulfate Precipitation<\/h2><\/div>\n        <p>When barium chloride solution is added to a solution containing sulfate ions, a white precipitate of <strong>barium sulfate<\/strong> forms.<\/p>\n        <div class=\"ols-definition-box\"><p><strong>Full equation:<\/strong> BaCl<sub>2<\/sub>(aq) + MgSO<sub>4<\/sub>(aq) \u2192 BaSO<sub>4<\/sub>(s) + MgCl<sub>2<\/sub>(aq)<\/p><\/div>\n        <p>The ions that form the insoluble precipitate are <strong>Ba<sup>2+<\/sup><\/strong> and <strong>SO<sub>4<\/sub><sup>2-<\/sup><\/strong>.<\/p>\n        <div class=\"ols-key-box\"><p><strong>Ionic equation:<\/strong> Ba<sup>2+<\/sup>(aq) + SO<sub>4<\/sub><sup>2-<\/sup>(aq) \u2192 BaSO<sub>4<\/sub>(s)<\/p><\/div>\n        <p>This reaction is used as a chemical test for sulfate ions. The sample is usually acidified before barium chloride solution is added.<\/p>\n      <\/article>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">8<\/div><h2>Ionic Equations Beyond Precipitation<\/h2><\/div>\n        <p>Ionic equations are also useful for displacement reactions because they show the species that gain or lose electrons, or the ions that are displaced.<\/p>\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Reaction type<\/th>\n                <th>Example full equation<\/th>\n                <th>Useful ionic equation<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Reaction type\">Metal displacement<\/td>\n                <td data-label=\"Example full equation\">Mg(s) + CuSO<sub>4<\/sub>(aq) \u2192 MgSO<sub>4<\/sub>(aq) + Cu(s)<\/td>\n                <td data-label=\"Useful ionic equation\">Mg(s) + Cu<sup>2+<\/sup>(aq) \u2192 Mg<sup>2+<\/sup>(aq) + Cu(s)<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Reaction type\">Halogen displacement<\/td>\n                <td data-label=\"Example full equation\">Cl<sub>2<\/sub>(aq) + 2KBr(aq) \u2192 2KCl(aq) + Br<sub>2<\/sub>(aq)<\/td>\n                <td data-label=\"Useful ionic equation\">Cl<sub>2<\/sub>(aq) + 2Br<sup>&#8211;<\/sup>(aq) \u2192 2Cl<sup>&#8211;<\/sup>(aq) + Br<sub>2<\/sub>(aq)<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n        <div class=\"ols-key-box\"><p><strong>Exam focus:<\/strong> spectator ions are not always sodium, potassium or nitrate ions, but these are very common because their compounds are usually soluble.<\/p><\/div>\n      <\/article>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\"><div class=\"ols-note-icon\">9<\/div><h2>Common Exam Points<\/h2><\/div>\n        <ul>\n          <li>Ionic equations show only the particles that actually change.<\/li>\n          <li>Spectator ions appear unchanged on both sides of the equation and are cancelled.<\/li>\n          <li>The state symbol (aq) means aqueous, which means dissolved in water.<\/li>\n          <li>Precipitation reactions form an insoluble solid from ions in solution.<\/li>\n          <li>For precipitation reactions, the precipitate is written as a solid with the state symbol (s).<\/li>\n          <li>Do not split solids, liquids, gases or covalent molecules into ions.<\/li>\n          <li>Always check that the final ionic equation is balanced for both atoms and charge.<\/li>\n          <li>Ag<sup>+<\/sup>(aq) + Cl<sup>&#8211;<\/sup>(aq) \u2192 AgCl(s) is the ionic equation for forming silver chloride.<\/li>\n          <li>Ba<sup>2+<\/sup>(aq) + SO<sub>4<\/sub><sup>2-<\/sup>(aq) \u2192 BaSO<sub>4<\/sub>(s) is the ionic equation for forming barium sulfate.<\/li>\n        <\/ul>\n      <\/article>\n\n      <section class=\"ols-h5p-card\">\n        <h2>Check Your Understanding<\/h2>\n        <p>Use this short activity to practise identifying the reacting ions and removing spectator ions from ionic equations.<\/p>\n        <div class=\"ols-h5p-grid\">\n          <div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-288\" class=\"h5p-iframe\" data-content-id=\"288\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Ionic Equations: Precipitation and Displacement\"><\/iframe><\/div><\/div>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-h5p-card\">\n        <h2>Extension Questions<\/h2>\n        <p>These are extension questions to practise applying ionic equations in different reaction contexts.<\/p>\n        <div class=\"ols-h5p-grid\">\n          <div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-289\" class=\"h5p-iframe\" data-content-id=\"289\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Full and Ionic Equations\"><\/iframe><\/div><\/div>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-quicksnap-card\">\n        <h2>QuickSnap<\/h2>\n        <p>This text summary condenses the page into the essential exam ideas.<\/p>\n        <ul class=\"ols-quicksnap-list\">\n          <li><strong>Ionic equations:<\/strong> show the particles that actually react.<\/li>\n          <li><strong>Spectator ions:<\/strong> ions that appear unchanged on both sides of the equation.<\/li>\n          <li><strong>Aqueous ions:<\/strong> ions in solution are shown using the state symbol (aq).<\/li>\n          <li><strong>Precipitation:<\/strong> two aqueous ions combine to form an insoluble solid.<\/li>\n          <li><strong>Silver chloride:<\/strong> Ag<sup>+<\/sup>(aq) + Cl<sup>&#8211;<\/sup>(aq) \u2192 AgCl(s).<\/li>\n          <li><strong>Barium sulfate:<\/strong> Ba<sup>2+<\/sup>(aq) + SO<sub>4<\/sub><sup>2-<\/sup>(aq) \u2192 BaSO<sub>4<\/sub>(s).<\/li>\n          <li><strong>Final check:<\/strong> atoms and overall charge must both balance.<\/li>\n        <\/ul>\n      <\/section>\n\n\n      <div class=\"ols-image-lightbox\" id=\"olsImageLightboxIonicEquations001\" aria-hidden=\"true\" role=\"dialog\" aria-modal=\"true\" aria-label=\"Expanded revision image\">\n        <div class=\"ols-image-lightbox-inner\">\n          <button class=\"ols-image-lightbox-close\" type=\"button\" aria-label=\"Close enlarged image\">\u00d7<\/button>\n          <img decoding=\"async\" class=\"ols-image-lightbox-img\" src=\"\" alt=\"\">\n        <\/div>\n      <\/div>\n\n      <script>\n        (function(){\n          var page = document.querySelector(\".ols-ionic-equations-page\");\n          if (!page) {\n            return;\n          }\n\n          var lightbox = page.querySelector(\"#olsImageLightboxIonicEquations001\");\n          if 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class=\"ols-course-cta-header-row\">\r\n\r\n          <div class=\"ols-course-cta-kicker\">\r\n            Complete Topic 5 Formulae, Equations & Amounts of Substance Course\r\n          <\/div>\r\n\r\n          <a class=\"ols-course-button ols-course-button-top\" href=\"https:\/\/onlinelearningsystem.net\/xyz\/shop\">\r\n            View Course\r\n          <\/a>\r\n\r\n        <\/div>\r\n\r\n        <h2>\r\n          Master Formulae, Equations and Amounts of Substance for Edexcel A Level Chemistry\r\n        <\/h2>\r\n\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-intro-stats\">\r\n\r\n      <p class=\"ols-course-cta-intro\">\r\n        Continue from these free revision notes into the full Topic 5 Formulae, Equations and Amounts of Substance course, with guided video teaching, diagnostic MCQ practice, teacher-marked short-answer questions and a specification assignment with a personalised progress report.\r\n      <\/p>\r\n\r\n      <div class=\"ols-course-cta-stats\">\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Guided learning<\/span>\r\n          <strong>Complete Topic 5<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Video lessons<\/span>\r\n          <strong>Full virtual lesson<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>MCQ practice<\/span>\r\n          <strong>123 marks<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>SAQ practice<\/span>\r\n          <strong>up to 145 marks<\/strong>\r\n        <\/div>\r\n\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-features\">\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Guided video teaching<\/h3>\r\n        <p>\r\n          Learn formulae, balanced equations, ionic equations, relative masses, mole calculations, empirical formulae, reacting masses, gas volumes, percentage yield and atom economy through structured video lessons with worked examples and walkthroughs.\r\n        <\/p>\r\n      <\/div>\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Instant MCQ feedback<\/h3>\r\n        <p>\r\n          Auto-marked MCQ quizzes provide immediate diagnostic feedback for every answer choice.\r\n        <\/p>\r\n      <\/div>\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Teacher-marked SAQs<\/h3>\r\n        <p>\r\n          Submit written exam responses and receive chemistry specialist feedback with improvement guidance.\r\n        <\/p>\r\n      <\/div>\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Progress tracking<\/h3>\r\n        <p>\r\n          Identify strengths and weaknesses across formulae, equations, mole calculations, concentration, empirical formulae, percentage yield, atom economy and test-tube reactions with targeted reporting.\r\n        <\/p>\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-animation-wrap\">\r\n\r\n      <h3 class=\"ols-course-animation-title\">\r\n        See how the course works\r\n      <\/h3>\r\n\r\n      <div class=\"ols-animation-frame-shell\">\r\n        <iframe\r\n          id=\"olsCourseAnimationFrame005\"\r\n          title=\"OLS course preview animation\"\r\n          loading=\"lazy\"\r\n          referrerpolicy=\"no-referrer\">\r\n        <\/iframe>\r\n\r\n        <button\r\n          class=\"ols-animation-start-overlay\"\r\n          id=\"olsCourseAnimationStart005\"\r\n          type=\"button\"\r\n          aria-label=\"Play OLS course preview animation\">\r\n          <span class=\"ols-animation-start-content\">\r\n            <span class=\"ols-animation-play-circle\" aria-hidden=\"true\">\r\n              <span class=\"ols-animation-play-icon\"><\/span>\r\n            <\/span>\r\n            <span class=\"ols-animation-start-text\">\r\n              Play course preview animation\r\n            <\/span>\r\n          <\/span>\r\n        <\/button>\r\n\r\n        <button\r\n          class=\"ols-animation-pause-button\"\r\n          id=\"olsCourseAnimationPause005\"\r\n          type=\"button\"\r\n          aria-label=\"Pause course preview animation\">\r\n          Pause\r\n        <\/button>\r\n      <\/div>\r\n\r\n      <p class=\"ols-course-video-status\">\r\n        Click play to start the course preview animation.\r\n      <\/p>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-bottom\">\r\n\r\n      <a class=\"ols-course-button\" href=\"https:\/\/onlinelearningsystem.net\/xyz\/shop\">\r\n        View Formulae, Equations & Amounts of Substance Topic 5 Course\r\n      <\/a>\r\n\r\n    <\/div>\r\n\r\n  <\/div>\r\n\r\n  <template id=\"olsCourseAnimationTemplate005\">\r\n<!DOCTYPE html>\r\n<html lang=\"en\">\r\n<head>\r\n<meta charset=\"UTF-8\">\r\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\r\n<title>OLS Combined Promo Animation<\/title>\r\n\r\n<style>\r\n*{box-sizing:border-box;}\r\n\r\nhtml.ols-animation-paused *,\r\nhtml.ols-animation-paused *::before,\r\nhtml.ols-animation-paused *::after{\r\n  animation-play-state:paused!important;\r\n}\r\n\r\n:root{\r\n  --ols-video-screen-w:1180;\r\n  --ols-video-screen-h:664;\r\n  --ols-video-screen-scale:1;\r\n  --ols-mcq-screen-w:1360;\r\n  --ols-mcq-screen-h:1130;\r\n  --ols-mcq-screen-scale:1;\r\n  --ols-saq-screen-w:1360;\r\n  --ols-saq-screen-h:965;\r\n  --ols-saq-screen-scale:1;\r\n}\r\n\r\nhtml,\r\nbody{\r\n  width:100%;\r\n  height:100%;\r\n}\r\n\r\nbody{\r\n  margin:0;\r\n  overflow:hidden;\r\n  font-family:Poppins,Arial,sans-serif;\r\n  background:#e9efff;\r\n}\r\n\r\n.ols-combined-stage{\r\n  position:relative;\r\n  width:100vw;\r\n  height:100vh;\r\n  overflow:hidden;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n}\r\n\r\n.ols-scene{\r\n  position:absolute;\r\n  inset:0;\r\n  width:100vw;\r\n  height:100vh;\r\n  opacity:0;\r\n  visibility:hidden;\r\n  pointer-events:none;\r\n}\r\n\r\n.ols-scene.active{\r\n  opacity:1;\r\n  visibility:visible;\r\n  pointer-events:auto;\r\n}\r\n\r\n.ols-scene.fade-out{\r\n  animation:olsSceneFadeOut 0.85s ease forwards;\r\n}\r\n\r\n@keyframes olsSceneFadeOut{\r\n  to{\r\n    opacity:0;\r\n    visibility:hidden;\r\n  }\r\n}\r\n\r\n.ols-title-cursor{\r\n  display:inline-block;\r\n  width:5px;\r\n  height:0.85em;\r\n  background:#1C244B;\r\n  margin-left:8px;\r\n  transform:translateY(8px);\r\n  animation:olsBlink 0.8s infinite;\r\n}\r\n\r\n.cursor{\r\n  display:inline-block;\r\n  width:3px;\r\n  height:28px;\r\n  background:#1c244b;\r\n  margin-left:3px;\r\n  transform:translateY(5px);\r\n  animation:olsBlink 0.8s infinite;\r\n}\r\n\r\n@keyframes olsBlink{\r\n  0%,45%{opacity:1;}\r\n  46%,100%{opacity:0;}\r\n}\r\n\r\n.ols-video-stage,\r\n.ols-mcq-stage,\r\n.ols-saq-stage{\r\n  width:100vw;\r\n  height:100vh;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  padding:0;\r\n  overflow:hidden;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n}\r\n\r\n.ols-video-title-screen,\r\n.ols-mcq-intro-screen,\r\n.ols-saq-intro{\r\n  position:absolute;\r\n  inset:0;\r\n  z-index:50;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n  opacity:1;\r\n  visibility:visible;\r\n  pointer-events:none;\r\n}\r\n\r\n.ols-video-title-screen.hide{animation:olsVideoTitleFadeOut 0.85s ease forwards;}\r\n.ols-mcq-intro-screen.hide{animation:olsMcqIntroFadeOut 0.85s ease forwards;}\r\n.ols-saq-intro.hide{animation:olsSaqIntroFadeOut 0.85s ease forwards;}\r\n\r\n@keyframes olsVideoTitleFadeOut{to{opacity:0;visibility:hidden;}}\r\n@keyframes olsMcqIntroFadeOut{to{opacity:0;visibility:hidden;}}\r\n@keyframes olsSaqIntroFadeOut{to{opacity:0;visibility:hidden;}}\r\n\r\n.ols-video-title-wrap,\r\n.ols-mcq-intro-title-wrap,\r\n.ols-saq-intro-title-wrap{\r\n  max-width:1250px;\r\n  padding:0 34px;\r\n  text-align:center;\r\n}\r\n\r\n.ols-video-title,\r\n.ols-mcq-intro-title,\r\n.ols-saq-intro-title{\r\n  margin:0;\r\n  font-family:Poppins,Arial,sans-serif;\r\n  font-size:clamp(52px,8vw,124px);\r\n  font-weight:600;\r\n  line-height:1.08;\r\n  color:#1C244B;\r\n  text-shadow:-9px 0 9px rgba(28,36,75,0.16);\r\n  letter-spacing:-0.045em;\r\n}\r\n\r\n#videoTitleText,\r\n#mcqIntroTitleText,\r\n#saqIntroTitleText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.ols-video-scene{\r\n  width:100%;\r\n  height:100%;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  opacity:0;\r\n  visibility:hidden;\r\n}\r\n\r\n.ols-video-scene.show{\r\n  visibility:visible;\r\n  animation:olsVideoSceneIn 1s ease forwards;\r\n}\r\n\r\n@keyframes olsVideoSceneIn{to{opacity:1;}}\r\n\r\n.ols-video-scale-wrap{\r\n  width:calc(var(--ols-video-screen-w) * 1px);\r\n  height:calc(var(--ols-video-screen-h) * 1px);\r\n  transform:scale(var(--ols-video-screen-scale));\r\n  transform-origin:center center;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n}\r\n\r\n.ols-video-card{\r\n  width:1180px;\r\n  height:664px;\r\n  border-radius:28px;\r\n  overflow:hidden;\r\n  background:#1C244B;\r\n  box-shadow:0 28px 80px rgba(28,36,75,0.28);\r\n  transform:translateY(24px) scale(0.96);\r\n  opacity:0;\r\n}\r\n\r\n.ols-video-scene.show .ols-video-card{\r\n  animation:olsVideoCardIn 1s cubic-bezier(.18,.89,.32,1.12) forwards;\r\n  animation-delay:0.2s;\r\n}\r\n\r\n@keyframes olsVideoCardIn{\r\n  to{\r\n    transform:translateY(0) scale(1);\r\n    opacity:1;\r\n  }\r\n}\r\n\r\n.ols-video-card video{\r\n  display:block;\r\n  width:100%;\r\n  height:100%;\r\n  aspect-ratio:16 \/ 9;\r\n  object-fit:cover;\r\n  border:0;\r\n}\r\n\r\n.ols-mcq-scale-wrap,\r\n.ols-saq-scale-wrap{\r\n  width:calc(var(--ols-mcq-screen-w) * 1px);\r\n  height:calc(var(--ols-mcq-screen-h) * 1px);\r\n  transform:scale(var(--ols-mcq-screen-scale));\r\n  transform-origin:center center;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:flex-start;\r\n}\r\n\r\n.ols-saq-scale-wrap{\r\n  width:calc(var(--ols-saq-screen-w) * 1px);\r\n  height:calc(var(--ols-saq-screen-h) * 1px);\r\n  transform:scale(var(--ols-saq-screen-scale));\r\n}\r\n\r\n.ols-mcq-screen{\r\n  width:1360px;\r\n  height:1130px;\r\n  border-radius:22px;\r\n  overflow:hidden;\r\n  background:#eaf0ff;\r\n  box-shadow:0 26px 70px rgba(28,36,75,0.22);\r\n  opacity:0;\r\n  transform:translateY(24px) scale(0.96);\r\n}\r\n\r\n.ols-mcq-screen.show{\r\n  animation:olsMcqScreenEnter 1s ease forwards;\r\n}\r\n\r\n@keyframes olsMcqScreenEnter{\r\n  from{opacity:0;transform:translateY(24px) scale(0.96);}\r\n  to{opacity:1;transform:translateY(0) scale(1);}\r\n}\r\n\r\n.mcq-question-area{\r\n  background:#eaf0ff;\r\n  padding:28px 30px 30px;\r\n  position:relative;\r\n  height:610px;\r\n}\r\n\r\n.mcq-question-lead{\r\n  margin:0 0 14px;\r\n  font-size:24px;\r\n  line-height:1.35;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-data-table{\r\n  border-collapse:collapse;\r\n  width:500px;\r\n  margin-bottom:8px;\r\n  font-size:21px;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-data-table th,\r\n.mcq-data-table td{\r\n  border:1.5px solid #c9ced8;\r\n  padding:12px 18px;\r\n  text-align:center;\r\n}\r\n\r\n.mcq-data-table th{\r\n  background:#f2f2f2;\r\n  font-weight:700;\r\n}\r\n\r\n.mcq-data-table td{\r\n  background:#eaf0ff;\r\n}\r\n\r\n.mcq-question-main{\r\n  margin:6px 0 28px;\r\n  font-size:24px;\r\n  line-height:1.35;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-options-wrap{\r\n  display:flex;\r\n  flex-direction:column;\r\n  gap:17px;\r\n  max-width:1200px;\r\n}\r\n\r\n.mcq-option-row{\r\n  display:flex;\r\n  align-items:center;\r\n  min-height:34px;\r\n  position:relative;\r\n}\r\n\r\n.mcq-radio{\r\n  width:28px;\r\n  height:28px;\r\n  border-radius:50%;\r\n  border:2px solid #6b7280;\r\n  margin-right:16px;\r\n  background:transparent;\r\n  position:relative;\r\n  flex:0 0 auto;\r\n}\r\n\r\n.mcq-radio::after{\r\n  content:\"\";\r\n  position:absolute;\r\n  inset:5px;\r\n  border-radius:50%;\r\n  background:#6b7280;\r\n  opacity:0;\r\n  transform:scale(0.4);\r\n  transition:opacity 0.25s ease,transform 0.25s ease;\r\n}\r\n\r\n.mcq-option-row.selected .mcq-radio::after{\r\n  opacity:1;\r\n  transform:scale(1);\r\n}\r\n\r\n.mcq-radio-ripple{\r\n  position:absolute;\r\n  left:14px;\r\n  top:50%;\r\n  width:28px;\r\n  height:28px;\r\n  border-radius:50%;\r\n  border:2px solid rgba(28,36,75,0.28);\r\n  transform:translate(-50%,-50%) scale(1);\r\n  opacity:0;\r\n  pointer-events:none;\r\n}\r\n\r\n.mcq-option-row.clicking .mcq-radio-ripple{\r\n  animation:mcqRipple 0.75s ease forwards;\r\n}\r\n\r\n@keyframes mcqRipple{\r\n  0%{opacity:0.65;transform:translate(-50%,-50%) scale(1);}\r\n  100%{opacity:0;transform:translate(-50%,-50%) scale(2.5);}\r\n}\r\n\r\n.mcq-option-label{\r\n  font-size:23px;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-specific-feedback{\r\n  display:inline-flex;\r\n  align-items:center;\r\n  margin-left:18px;\r\n  min-height:38px;\r\n  opacity:0;\r\n  transform:translateX(-8px);\r\n}\r\n\r\n.mcq-specific-feedback.show{\r\n  opacity:1;\r\n  transform:translateX(0);\r\n  transition:opacity 0.35s ease,transform 0.35s ease;\r\n}\r\n\r\n.mcq-cross-icon{\r\n  width:26px;\r\n  height:26px;\r\n  border-radius:50%;\r\n  border:2px solid #d83255;\r\n  color:#d83255;\r\n  display:inline-flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  font-size:18px;\r\n  font-weight:700;\r\n  margin-right:12px;\r\n  opacity:0;\r\n  transform:scale(0.4);\r\n}\r\n\r\n.mcq-cross-icon.show{\r\n  animation:mcqCrossPop 0.35s ease forwards;\r\n}\r\n\r\n@keyframes mcqCrossPop{\r\n  70%{opacity:1;transform:scale(1.18);}\r\n  100%{opacity:1;transform:scale(1);}\r\n}\r\n\r\n.mcq-specific-feedback-text{\r\n  display:inline-block;\r\n  background:#fff4b8;\r\n  color:#111827;\r\n  padding:8px 16px;\r\n  font-size:22px;\r\n  line-height:1.35;\r\n  min-width:850px;\r\n  min-height:44px;\r\n}\r\n\r\n.mcq-submit-button{\r\n  position:absolute;\r\n  right:34px;\r\n  bottom:30px;\r\n  border:0;\r\n  border-radius:999px;\r\n  background:#1C244B;\r\n  color:#ffffff;\r\n  padding:14px 28px;\r\n  font-size:18px;\r\n  font-weight:600;\r\n  box-shadow:0 14px 32px rgba(28,36,75,0.25);\r\n  cursor:default;\r\n  transition:transform 0.2s ease,box-shadow 0.2s ease,background 0.2s ease;\r\n}\r\n\r\n.mcq-submit-button.clicked{\r\n  transform:translateY(2px) scale(0.97);\r\n  background:#26315f;\r\n  box-shadow:0 7px 18px rgba(28,36,75,0.22);\r\n}\r\n\r\n.mcq-general-feedback{\r\n  height:520px;\r\n  background:#fff3c9;\r\n  color:#8a6a00;\r\n  padding:26px 30px 28px;\r\n  font-size:23px;\r\n  line-height:1.34;\r\n  opacity:0;\r\n  transform:translateY(20px);\r\n  transition:opacity 0.7s ease,transform 0.7s ease;\r\n  overflow:hidden;\r\n}\r\n\r\n.mcq-general-feedback.show{\r\n  opacity:1;\r\n  transform:translateY(0);\r\n}\r\n\r\n#mcqGeneralText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.mcq-specific-cursor{background:#111827;}\r\n.mcq-general-cursor{background:#8a6a00;}\r\n\r\n.ols-saq-screen{\r\n  width:1360px;\r\n  height:965px;\r\n  border-radius:22px;\r\n  overflow:hidden;\r\n  background:#eaf0ff;\r\n  box-shadow:0 26px 70px rgba(28,36,75,0.22);\r\n  opacity:0;\r\n  transform:translateY(24px) scale(0.96);\r\n}\r\n\r\n.ols-saq-screen.show{\r\n  animation:olsSaqScreenEnter 1s ease forwards;\r\n}\r\n\r\n@keyframes olsSaqScreenEnter{\r\n  from{opacity:0;transform:translateY(24px) scale(0.96);}\r\n  to{opacity:1;transform:translateY(0) scale(1);}\r\n}\r\n\r\n.saq-question-area{\r\n  height:335px;\r\n  background:#eaf0ff;\r\n  padding:30px 40px 32px;\r\n}\r\n\r\n.saq-question-text{\r\n  font-size:25px;\r\n  line-height:1.42;\r\n  color:#111827;\r\n  margin-bottom:22px;\r\n}\r\n\r\n.saq-student-box{\r\n  height:195px;\r\n  background:#f3f4f6;\r\n  border:2px solid #cfd6e3;\r\n  border-radius:8px;\r\n  padding:23px 26px;\r\n  font-size:24px;\r\n  line-height:1.55;\r\n  color:#4b5563;\r\n  position:relative;\r\n  overflow:hidden;\r\n}\r\n\r\n.saq-teacher-feedback{\r\n  height:630px;\r\n  background:#dff3e6;\r\n  color:#075f3b;\r\n  padding:28px 40px 30px;\r\n  font-size:23px;\r\n  line-height:1.47;\r\n  opacity:0;\r\n  transform:translateY(20px);\r\n  transition:opacity 0.7s ease,transform 0.7s ease;\r\n  overflow:hidden;\r\n}\r\n\r\n.saq-teacher-feedback.show{\r\n  opacity:1;\r\n  transform:translateY(0);\r\n}\r\n\r\n#saqTeacherText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.saq-teacher-cursor{\r\n  background:#075f3b;\r\n}\r\n\r\n@media(max-width:900px){\r\n  .ols-video-title,\r\n  .ols-mcq-intro-title,\r\n  .ols-saq-intro-title{\r\n    font-size:clamp(42px,11vw,78px);\r\n    line-height:1.12;\r\n  }\r\n\r\n  .ols-title-cursor{\r\n    width:4px;\r\n    margin-left:6px;\r\n  }\r\n\r\n  .ols-video-card{\r\n    border-radius:20px;\r\n  }\r\n}\r\n<\/style>\r\n<\/head>\r\n\r\n<body>\r\n<div class=\"ols-combined-stage\">\r\n\r\n  <section id=\"sceneVideo\" class=\"ols-scene active\">\r\n    <div class=\"ols-video-stage\">\r\n      <div id=\"videoTitleScreen\" class=\"ols-video-title-screen\">\r\n        <div class=\"ols-video-title-wrap\">\r\n          <h1 class=\"ols-video-title\">\r\n            <span id=\"videoTitleText\"><\/span><span id=\"videoTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <section id=\"videoScene\" class=\"ols-video-scene\">\r\n        <div class=\"ols-video-scale-wrap\">\r\n          <div class=\"ols-video-card\">\r\n            <video\r\n              id=\"lessonVideo\"\r\n              src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Virtual-Lesson.mp4\"\r\n              muted\r\n              playsinline\r\n              preload=\"auto\">\r\n            <\/video>\r\n          <\/div>\r\n        <\/div>\r\n      <\/section>\r\n    <\/div>\r\n  <\/section>\r\n\r\n  <section id=\"sceneMcq\" class=\"ols-scene\">\r\n    <div class=\"ols-mcq-stage\">\r\n      <div id=\"mcqIntroScreen\" class=\"ols-mcq-intro-screen\">\r\n        <div class=\"ols-mcq-intro-title-wrap\">\r\n          <h1 class=\"ols-mcq-intro-title\">\r\n            <span id=\"mcqIntroTitleText\"><\/span><span id=\"mcqIntroTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <div class=\"ols-mcq-scale-wrap\">\r\n        <main id=\"mcqScreen\" class=\"ols-mcq-screen\">\r\n          <section class=\"mcq-question-area\">\r\n            <p class=\"mcq-question-lead\">A compound contains carbon, hydrogen and oxygen only. Its percentage composition by mass is shown.<\/p>\r\n\r\n            <table class=\"mcq-data-table\">\r\n              <thead>\r\n                <tr>\r\n                  <th>Element<\/th>\r\n                  <th>Percentage by mass<\/th>\r\n                <\/tr>\r\n              <\/thead>\r\n              <tbody>\r\n                <tr><td>C<\/td><td>40.0%<\/td><\/tr>\r\n                <tr><td>H<\/td><td>6.7%<\/td><\/tr>\r\n                <tr><td>O<\/td><td>53.3%<\/td><\/tr>\r\n              <\/tbody>\r\n            <\/table>\r\n\r\n            <p class=\"mcq-question-main\">What is the empirical formula of the compound?<\/p>\r\n\r\n            <div class=\"mcq-options-wrap\">\r\n              <div id=\"mcqWrongOption\" class=\"mcq-option-row\">\r\n                <span class=\"mcq-radio\"><\/span>\r\n                <span class=\"mcq-radio-ripple\"><\/span>\r\n                <span class=\"mcq-option-label\">C<sub>2<\/sub>H<sub>4<\/sub>O<sub>2<\/sub><\/span>\r\n\r\n                <span id=\"mcqSpecificFeedback\" class=\"mcq-specific-feedback\">\r\n                  <span id=\"mcqCrossIcon\" class=\"mcq-cross-icon\">\u00d7<\/span>\r\n                  <span class=\"mcq-specific-feedback-text\">\r\n                    <span id=\"mcqSpecificText\"><\/span><span id=\"mcqSpecificCursor\" class=\"cursor mcq-specific-cursor\" style=\"display:none;\"><\/span>\r\n                  <\/span>\r\n                <\/span>\r\n              <\/div>\r\n\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">CH<sub>2<\/sub>O<\/span><\/div>\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">CHO<\/span><\/div>\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">CH<sub>4<\/sub>O<\/span><\/div>\r\n            <\/div>\r\n\r\n            <button id=\"mcqSubmitButton\" class=\"mcq-submit-button\">Submit answer<\/button>\r\n          <\/section>\r\n\r\n          <section id=\"mcqGeneralFeedback\" class=\"mcq-general-feedback\">\r\n            <span id=\"mcqGeneralText\"><\/span><span id=\"mcqGeneralCursor\" class=\"cursor mcq-general-cursor\" style=\"display:none;\"><\/span>\r\n          <\/section>\r\n        <\/main>\r\n      <\/div>\r\n    <\/div>\r\n  <\/section>\r\n\r\n  <section id=\"sceneSaq\" class=\"ols-scene\">\r\n    <div class=\"ols-saq-stage\">\r\n      <div id=\"saqIntro\" class=\"ols-saq-intro\">\r\n        <div class=\"ols-saq-intro-title-wrap\">\r\n          <h1 class=\"ols-saq-intro-title\">\r\n            <span id=\"saqIntroTitleText\"><\/span><span id=\"saqIntroTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <div class=\"ols-saq-scale-wrap\">\r\n        <main id=\"saqScreen\" class=\"ols-saq-screen\">\r\n          <section class=\"saq-question-area\">\r\n            <div class=\"saq-question-text\">\r\n              <strong>(ii)<\/strong>&nbsp;&nbsp; A student reacts magnesium with hydrochloric acid and collects hydrogen gas.<br>\r\n              Explain how the volume of hydrogen can be used to calculate the amount of magnesium that reacted.\r\n            <\/div>\r\n\r\n            <div class=\"saq-student-box\">\r\n              <span id=\"saqStudentText\"><\/span><span id=\"saqStudentCursor\" class=\"cursor\"><\/span>\r\n            <\/div>\r\n          <\/section>\r\n\r\n          <section id=\"saqTeacherFeedback\" class=\"saq-teacher-feedback\">\r\n            <span id=\"saqTeacherText\"><\/span><span id=\"saqTeacherCursor\" class=\"cursor saq-teacher-cursor\" style=\"display:none;\"><\/span>\r\n          <\/section>\r\n        <\/main>\r\n      <\/div>\r\n    <\/div>\r\n  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The empirical formula must show the simplest whole-number ratio.\";\r\nconst mcqGeneralFeedbackText=\r\n\"Your answer is incorrect.\\n\\n\"+\r\n\"To find an empirical formula from percentage composition, assume 100 g of the compound, then convert each mass into moles.\\n\\n\"+\r\n\"\u2022 Carbon: 40.0 \u00f7 12.0 = 3.33 mol.\\n\"+\r\n\"\u2022 Hydrogen: 6.7 \u00f7 1.0 = 6.7 mol.\\n\"+\r\n\"\u2022 Oxygen: 53.3 \u00f7 16.0 = 3.33 mol.\\n\"+\r\n\"\u2022 Divide all values by the smallest value, 3.33.\\n\"+\r\n\"\u2022 The ratio is C : H : O = 1 : 2 : 1.\\n\\n\"+\r\n\"Therefore, the empirical formula is CH\u2082O.\\n\\n\"+\r\n\"The correct answer is: CH\u2082O\";\r\n\r\nconst mcqIntroScreen=document.getElementById(\"mcqIntroScreen\");\r\nconst mcqIntroTitleText=document.getElementById(\"mcqIntroTitleText\");\r\nconst mcqIntroTitleCursor=document.getElementById(\"mcqIntroTitleCursor\");\r\nconst mcqScreen=document.getElementById(\"mcqScreen\");\r\nconst mcqWrongOption=document.getElementById(\"mcqWrongOption\");\r\nconst mcqSubmitButton=document.getElementById(\"mcqSubmitButton\");\r\nconst mcqSpecificFeedback=document.getElementById(\"mcqSpecificFeedback\");\r\nconst mcqCrossIcon=document.getElementById(\"mcqCrossIcon\");\r\nconst mcqSpecificText=document.getElementById(\"mcqSpecificText\");\r\nconst mcqSpecificCursor=document.getElementById(\"mcqSpecificCursor\");\r\nconst mcqGeneralFeedback=document.getElementById(\"mcqGeneralFeedback\");\r\nconst mcqGeneralText=document.getElementById(\"mcqGeneralText\");\r\nconst mcqGeneralCursor=document.getElementById(\"mcqGeneralCursor\");\r\n\r\nfunction selectMcqWrongOption(){\r\n  mcqWrongOption.classList.add(\"clicking\");\r\n\r\n  setTimeout(function(){\r\n    mcqWrongOption.classList.add(\"selected\");\r\n  },220);\r\n\r\n  setTimeout(function(){\r\n    mcqWrongOption.classList.remove(\"clicking\");\r\n  },850);\r\n}\r\n\r\nfunction clickMcqSubmit(){\r\n  mcqSubmitButton.classList.add(\"clicked\");\r\n\r\n  setTimeout(function(){\r\n    mcqSubmitButton.classList.remove(\"clicked\");\r\n  },240);\r\n}\r\n\r\nfunction showMcqSpecificFeedback(){\r\n  mcqSpecificFeedback.classList.add(\"show\");\r\n\r\n  setTimeout(function(){\r\n    mcqCrossIcon.classList.add(\"show\");\r\n  },180);\r\n\r\n  setTimeout(function(){\r\n    mcqSpecificCursor.style.display=\"inline-block\";\r\n\r\n    typeWriter(mcqSpecificText,mcqSpecificFeedbackText,12,function(){\r\n      mcqSpecificCursor.style.display=\"none\";\r\n\r\n      setTimeout(function(){\r\n        showMcqGeneralFeedback();\r\n      },650);\r\n    });\r\n  },560);\r\n}\r\n\r\nfunction showMcqGeneralFeedback(){\r\n  mcqGeneralFeedback.classList.add(\"show\");\r\n\r\n  setTimeout(function(){\r\n    mcqGeneralCursor.style.display=\"inline-block\";\r\n\r\n    typeWriter(mcqGeneralText,mcqGeneralFeedbackText,8,function(){\r\n      mcqGeneralCursor.style.display=\"none\";\r\n\r\n      setTimeout(function(){\r\n        switchScene(sceneMcq,sceneSaq,function(){\r\n          startSaqIntro();\r\n        });\r\n      },2600);\r\n    });\r\n  },600);\r\n}\r\n\r\nfunction startMcqAnimation(){\r\n  fitMcqScreen();\r\n  mcqScreen.classList.add(\"show\");\r\n\r\n  setTimeout(function(){\r\n    selectMcqWrongOption();\r\n\r\n    setTimeout(function(){\r\n      clickMcqSubmit();\r\n\r\n      setTimeout(function(){\r\n        showMcqSpecificFeedback();\r\n      },620);\r\n    },1150);\r\n  },1300);\r\n}\r\n\r\nfunction startMcqIntro(){\r\n  fitMcqScreen();\r\n\r\n  setTimeout(function(){\r\n    typeWriter(mcqIntroTitleText,mcqIntroTitle,44,function(){\r\n      setTimeout(function(){\r\n        mcqIntroTitleCursor.style.display=\"none\";\r\n\r\n        setTimeout(function(){\r\n          mcqIntroScreen.classList.add(\"hide\");\r\n\r\n          setTimeout(function(){\r\n            startMcqAnimation();\r\n          },850);\r\n        },3000);\r\n      },250);\r\n    });\r\n  },700);\r\n}\r\n\r\nconst saqIntroTitle=\"Chemistry Specialist\\nMarked Exam Feedback\";\r\nconst saqStudentAnswer=\"You measure the gas volume and use it to find the number of moles, then use the equation to find magnesium.\";\r\nconst saqTeacherFeedbackText=\r\n\"Comment:\\n\"+\r\n\"This answer is on the right track, but it needs the calculation sequence and the balanced equation to be exam-standard.\\n\\n\"+\r\n\"Magnesium reacts with hydrochloric acid according to the equation Mg + 2HCl \u2192 MgCl\u2082 + H\u2082. The mole ratio between magnesium and hydrogen is 1 : 1, so the amount of hydrogen produced is equal to the amount of magnesium that reacted.\\n\\n\"+\r\n\"The volume of hydrogen can be converted into moles using the molar volume of gas, or pV = nRT if pressure and temperature data are supplied. Once the moles of H\u2082 are known, the 1 : 1 ratio gives the moles of Mg. The mass of magnesium can then be calculated using mass = moles \u00d7 molar mass.\\n\\n\"+\r\n\"Next time, include:\\n\"+\r\n\"\u2022 The balanced equation: Mg + 2HCl \u2192 MgCl\u2082 + H\u2082 \u2713\\n\"+\r\n\"\u2022 Convert gas volume into moles of H\u2082 \u2713\\n\"+\r\n\"\u2022 Use the 1 : 1 mole ratio between Mg and H\u2082 \u2713\\n\"+\r\n\"\u2022 Convert moles of Mg into mass if required \u2713\\n\\n\"+\r\n\"You identified the main idea, but the strongest answers show the equation, mole ratio and calculation route clearly.\";\r\n\r\nconst saqIntro=document.getElementById(\"saqIntro\");\r\nconst saqIntroTitleText=document.getElementById(\"saqIntroTitleText\");\r\nconst saqIntroTitleCursor=document.getElementById(\"saqIntroTitleCursor\");\r\nconst saqStudentText=document.getElementById(\"saqStudentText\");\r\nconst saqTeacherText=document.getElementById(\"saqTeacherText\");\r\nconst saqStudentCursor=document.getElementById(\"saqStudentCursor\");\r\nconst saqTeacherCursor=document.getElementById(\"saqTeacherCursor\");\r\nconst saqFeedbackBox=document.getElementById(\"saqTeacherFeedback\");\r\nconst saqScreen=document.getElementById(\"saqScreen\");\r\n\r\nfunction startSaqFeedbackAnimation(){\r\n  fitSaqScreen();\r\n  saqScreen.classList.add(\"show\");\r\n\r\n  setTimeout(function(){\r\n    typeWriter(saqStudentText,saqStudentAnswer,27,function(){\r\n      saqStudentCursor.style.display=\"none\";\r\n\r\n      setTimeout(function(){\r\n        saqFeedbackBox.classList.add(\"show\");\r\n        saqTeacherCursor.style.display=\"inline-block\";\r\n\r\n        typeWriter(saqTeacherText,saqTeacherFeedbackText,10,function(){\r\n          saqTeacherCursor.style.display=\"none\";\r\n        });\r\n      },650);\r\n    });\r\n  },850);\r\n}\r\n\r\nfunction startSaqIntro(){\r\n  fitSaqScreen();\r\n\r\n  setTimeout(function(){\r\n    typeWriter(saqIntroTitleText,saqIntroTitle,44,function(){\r\n      setTimeout(function(){\r\n        saqIntroTitleCursor.style.display=\"none\";\r\n\r\n        setTimeout(function(){\r\n          saqIntro.classList.add(\"hide\");\r\n\r\n          setTimeout(function(){\r\n            startSaqFeedbackAnimation();\r\n          },850);\r\n        },3000);\r\n      },250);\r\n    });\r\n  },700);\r\n}\r\n\r\nstartVideoSection();\r\n<\/script>\r\n<\/body>\r\n<\/html>\r\n  <\/template>\r\n\r\n  <script>\r\n    (function(){\r\n      var startButton = document.getElementById(\"olsCourseAnimationStart005\");\r\n      var pauseButton = document.getElementById(\"olsCourseAnimationPause005\");\r\n      var iframe = document.getElementById(\"olsCourseAnimationFrame005\");\r\n      var template = document.getElementById(\"olsCourseAnimationTemplate005\");\r\n\r\n      if (!startButton || !pauseButton || !iframe || !template) {\r\n        return;\r\n      }\r\n\r\n      startButton.addEventListener(\"click\", function(){\r\n        iframe.setAttribute(\"srcdoc\", template.innerHTML);\r\n        startButton.classList.add(\"is-hidden\");\r\n        pauseButton.classList.add(\"is-visible\");\r\n        pauseButton.textContent = \"Pause\";\r\n        pauseButton.setAttribute(\"aria-label\", \"Pause course preview animation\");\r\n      });\r\n\r\n      pauseButton.addEventListener(\"click\", function(){\r\n        if (!iframe.contentWindow || typeof iframe.contentWindow.olsToggleAnimationPause !== \"function\") {\r\n          return;\r\n        }\r\n\r\n        var state = iframe.contentWindow.olsToggleAnimationPause();\r\n\r\n        if (state === \"paused\") {\r\n          pauseButton.textContent = \"Resume\";\r\n          pauseButton.setAttribute(\"aria-label\", \"Resume course preview animation\");\r\n        } else {\r\n          pauseButton.textContent = \"Pause\";\r\n          pauseButton.setAttribute(\"aria-label\", \"Pause course preview animation\");\r\n        }\r\n      });\r\n    })();\r\n  <\/script>\r\n<\/section>\n\n      <section class=\"ols-faq-card\">\n        <h2>FAQs<\/h2>\n        <p>These questions address the most common misconceptions students have when learning ionic equations.<\/p>\n        <div class=\"ols-faq-list\">\n          <div class=\"ols-faq-item\">\n            <h3>What is an ionic equation?<\/h3>\n            <p>An ionic equation is an equation that shows the particles that actually take part in a reaction. Spectator ions are removed because they do not change.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>What is a spectator ion?<\/h3>\n            <p>A spectator ion is an ion that remains unchanged during a reaction. It appears on both sides of the full ionic equation with the same charge and state symbol.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Why do precipitates form?<\/h3>\n            <p>A precipitate forms when ions in solution combine to make an insoluble solid. For example, Ag<sup>+<\/sup>(aq) and Cl<sup>&#8211;<\/sup>(aq) form AgCl(s).<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Do I split every compound into ions?<\/h3>\n            <p>No. Only aqueous ionic substances are split into ions. Solids, liquids, gases and covalent molecules are normally kept together.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>How do I check my ionic equation is correct?<\/h3>\n            <p>Check that the atoms balance and that the total charge on the left equals the total charge on the right. A chemically correct ionic equation must satisfy both checks.<\/p>\n          <\/div>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-related-card\">\n        <h2>Related Topics<\/h2>\n        <p>Build the surrounding skills needed to write and interpret ionic equations confidently.<\/p>\n        <div class=\"ols-related-grid\">\n          <a class=\"ols-related-item\" 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>\n          <a class=\"ols-related-item\" 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>\n          <a class=\"ols-related-item\" 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>\n          <a class=\"ols-related-item\" 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>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/empirical-and-molecular-formulae\/\">Formulae<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/\">Topic 5 Overview<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card\">\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\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\/topic-5-formulae-equations-and-amounts-of-substance\/ionic-and-full-equations\/#webpage\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/ionic-and-full-equations\/\",\n            \"name\": \"Ionic Equations - Edexcel A Level Chemistry\",\n            \"description\": \"Revise ionic equations, spectator ions, state symbols and precipitation reactions for Edexcel A Level Chemistry Topic 5.\",\n            \"inLanguage\": \"en-GB\",\n            \"isPartOf\": {\n             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