{"id":7809,"date":"2026-09-13T19:08:58","date_gmt":"2026-09-13T18:08:58","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/metallic-bonding-and-structure\/"},"modified":"2026-09-26T10:25:50","modified_gmt":"2026-09-26T09:25:50","slug":"metallic-bonding-and-structure","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/metallic-bonding-and-structure\/","title":{"rendered":"Metallic Bonding and Structure"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-metallic-bonding-structure-9ch0-page\">\n  <style>\n    .ols-revision-page {\n      --navy: #1C244B;\n      --blue: #2563eb;\n      --soft-blue: #eef4ff;\n      --soft-red: #fff7f7;\n      --soft-purple: #f7f0ff;\n      --soft-green: #f0f7f1;\n      --soft-orange: #fff7ed;\n      --soft-gold: #fff8e8;\n      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text-align: center; line-height: 1.6; }\n    .ols-figure-placeholder .ols-figure-image { background: transparent; }\n    .ols-figure-placeholder { background: #ffffff; border: 1px solid rgba(28, 36, 75, 0.12); border-radius: 22px; padding: 14px; margin: 18px 0 6px; }\n    .ols-figure-placeholder .ols-figure-caption p { margin: 10px 0 0; font-size: 14px; color: #667085; text-align: center; }\n<\/style>\n\n    <aside class=\"ols-sidebar\">\n  <div class=\"ols-sidebar-header\">\n    <h3>Revision Notes<\/h3>\n    <p>Cambridge International AS Level Chemistry<\/p>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>3.3 Metallic Bonding<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/\">Part overview<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/metallic-bonding-and-structure\/\">Metallic Bonding and Structure<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/physical-properties-of-metals\/\">Physical Properties of Metals<\/a><\/li>\n    <\/ul>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>Other Topic 3 Parts<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/\">Topic 3 overview<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/electronegativity\/\">3.1 Electronegativity<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/ionic-bonding\/\">3.2 Ionic Bonding<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/\">3.4 Covalent Bonding<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/shapes-of-molecules\/\">3.5 Shapes of Molecules<\/a><\/li>\n    <\/ul>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>Related<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-4-states-of-matter\/structure-types\/\">Topic 4: Structure Types<\/a><\/li>\n    <\/ul>\n  <\/div>\n<\/aside>\n<script>\r\n(function() {\r\n  function normalisePath(path) {\r\n    return String(path || '')\r\n      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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\/cie\/\">Cambridge International (CIE)<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/\">Topic 3 Chemical Bonding<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/\">3.3 Metallic Bonding<\/a> \/\n<span>Metallic Bonding and Structure<\/span>\n<\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Metallic Bonding &amp; Structure<\/h1>\n        <p class=\"ols-page-intro\">A concise revision guide to metallic bonding, giant metallic lattice structures, positive metal ions, delocalised electrons and the factors that affect metallic bonding strength.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">AS Level<\/div>\n<div class=\"ols-badge\">Topic 3: Chemical Bonding<\/div>\n<div class=\"ols-badge\">9701 Papers 1 and 2<\/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\">\n                <path d=\"M4.98 3.5C4.98 4.88 3.86 6 2.48 6S0 4.88 0 3.5 1.12 1 2.48 1s2.5 1.12 2.5 2.5zM.5 8h4V24h-4V8zm7 0h3.8v2.2h.1c.5-.9 1.8-2.2 3.9-2.2 4.2 0 5 2.8 5 6.4V24h-4v-7.6c0-1.8 0-4.2-2.6-4.2s-3 2-3 4v7.8h-4V8z\"><\/path>\n              <\/svg>\n              View LinkedIn Profile\n            <\/a>\n          <\/div>\n        <\/div>\n      <\/header>\n\n      <section class=\"ols-h5p-card ols-h5p-inline ols-h5p-recap\">\n<span class=\"ols-h5p-kicker\">Before you start<\/span>\n<h2>GCSE Recap: The Model of a Metal<\/h2>\n<p>Before you start, check that you remember the GCSE picture of metallic bonding.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-content\" data-content-id=\"603\"><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">1<\/div>\n          <h2>What Is Metallic Bonding?<\/h2>\n        <\/div>\n\n        <p><strong>Metallic bonding<\/strong> is the electrostatic force of attraction between <strong>positive metal ions<\/strong> and <strong>delocalised electrons<\/strong>.<\/p>\n        <p>When metal atoms form a metallic lattice, their outer-shell electrons become delocalised. These electrons are not attached to one particular atom and can move through the structure.<\/p>\n        <p>The metal atoms are left as positive ions. The attraction between these positive ions and the delocalised electrons holds the metal lattice together.<\/p>\n\n        <div class=\"ols-definition-box\">\n          <p><strong>Definition:<\/strong> Metallic bonding is the strong electrostatic attraction between a regular lattice of positive metal ions and a sea of delocalised electrons.<\/p>\n        <\/div>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Key idea:<\/strong> A metal is not made from separate molecules. It is a giant metallic lattice held together by attraction between positive ions and delocalised electrons.<\/p>\n        <\/div>\n      <\/article>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">2<\/div>\n          <h2>Giant Metallic Lattice Structure<\/h2>\n        <\/div>\n\n        <p>Metals exist as <strong>giant metallic lattice structures<\/strong>. The positive metal ions are arranged in a <strong>regular, closely packed lattice<\/strong>.<\/p>\n        <p>The outer-shell electrons are <strong>delocalised<\/strong>, meaning they are free to move through the lattice. This leaves behind positive metal ions such as <strong>Na<sup>+<\/sup><\/strong>, <strong>Mg<sup>2+<\/sup><\/strong> and <strong>Al<sup>3+<\/sup><\/strong>.<\/p>\n        <p>The structure can be described as <strong>layers of positive metal ions surrounded by delocalised electrons<\/strong>.<\/p>\n\n        <div class=\"ols-zoom-card wide\">\n          <div class=\"ols-zoom-card-image\">\n            <img decoding=\"async\" class=\"ols-zoomable-img ols-lightbox-target\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/metallic-bonding.webp\" alt=\"Giant metallic lattice structure showing positive Mg2+ ions surrounded by a sea of delocalised electrons\">\n          <\/div>\n          <div class=\"ols-zoom-card-caption\">\n            <p>The diagram shows positive metal ions in fixed lattice positions surrounded by delocalised electrons.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Ions and Electrons in New Metals<\/h2>\n<p>Answer five quick questions on metals that this page has not mentioned.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-225\" class=\"h5p-iframe\" data-content-id=\"225\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Metallic Bonding Quick Fire: Ions and Delocalised Electrons in New Metals\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <!-- 3D card: metallic-bonding (swapped 26 Sep 2026) -->\n<section class=\"ols-met-001\" id=\"olsMet001\">\n<style>\n@import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600&display=swap');\n\n.ols-met-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  color:#1C244B; 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text-align:center; font-size:11px; font-style:italic; color:#aab0c0;\n}\n.ols-cc-met-001 a{color:#aab0c0; text-decoration:none;}\n.ols-cc-met-001 a:hover{text-decoration:underline;}\n<\/style>\n\n<div class=\"met-head\">\n  <h2 class=\"met-title\">Metallic Bonding in Sodium<\/h2>\n  <p class=\"met-sub\">Build sodium from its lattice of Na<sup>+<\/sup> ions and the sea of delocalised electrons around them, then see how metallic bonding explains conductivity, malleability and melting point.<\/p>\n<\/div>\n\n<div class=\"met-stage\" id=\"metStage\">\n  <canvas class=\"met-canvas\" id=\"metCanvas\"><\/canvas>\n  <div class=\"met-overlay\" id=\"metOverlay\"><\/div>\n  <div class=\"met-caption\" id=\"metCaption\"><\/div>\n  <div class=\"met-hint\" id=\"metHint\">Drag to rotate<\/div>\n  <div class=\"met-badges\" id=\"metBadges\"><\/div>\n<\/div>\n\n<div class=\"met-controls\">\n  <div class=\"met-row\">\n    <span class=\"met-rowlab\">Step<\/span>\n    <div class=\"met-seg\" role=\"group\" aria-label=\"Step\">\n      <button type=\"button\" data-step=\"1\" aria-pressed=\"true\">Unit cell<\/button>\n      <button type=\"button\" data-step=\"2\" aria-pressed=\"false\">Delocalised electrons<\/button>\n      <button type=\"button\" data-step=\"3\" aria-pressed=\"false\">Giant lattice<\/button>\n      <button type=\"button\" data-step=\"4\" aria-pressed=\"false\">Properties<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"met-row is-hidden\" id=\"metRowP\">\n    <span class=\"met-rowlab\">Property<\/span>\n    <div class=\"met-seg\" role=\"group\" aria-label=\"Property\">\n      <button type=\"button\" data-p=\"cond\" aria-pressed=\"true\">Conductivity<\/button>\n      <button type=\"button\" data-p=\"mall\" aria-pressed=\"false\">Malleability<\/button>\n      <button type=\"button\" data-p=\"namg\" aria-pressed=\"false\">Na vs Mg<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"met-row\">\n    <span class=\"met-rowlab\">View<\/span>\n    <div class=\"met-seg\" role=\"group\" aria-label=\"Camera view\">\n      <button type=\"button\" data-v=\"front\" aria-pressed=\"false\">Front<\/button>\n      <button type=\"button\" data-v=\"side\" aria-pressed=\"false\">Side<\/button>\n      <button type=\"button\" data-v=\"top\" aria-pressed=\"false\">Top<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"met-row\">\n    <span class=\"met-rowlab\">Show<\/span>\n    <button type=\"button\" class=\"met-pill p-red\" id=\"metTogPart\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Electrons as particles<\/button>\n    <button type=\"button\" class=\"met-pill p-red\" id=\"metTogSea\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Electron sea<\/button>\n    <button type=\"button\" class=\"met-pill\" id=\"metTogCell\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Unit cell outline<\/button>\n    <button type=\"button\" class=\"met-pill\" id=\"metTogLab\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Labels<\/button>\n    <button type=\"button\" class=\"met-pill\" id=\"metTogMove\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Electron motion<\/button>\n  <\/div>\n\n  <div class=\"met-row\">\n    <span class=\"met-rowlab\">Motion<\/span>\n    <button type=\"button\" class=\"met-pill\" id=\"metSpin\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Rotation<\/button>\n    <button type=\"button\" class=\"met-pill\" id=\"metResetV\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"met-info\">\n  <h3 id=\"metInfoTitle\"><\/h3>\n  <p id=\"metInfoText\"><\/p>\n  <div class=\"met-facts\" id=\"metFacts\"><\/div>\n  <div class=\"met-key\">\n    <span><i style=\"background:#b0b6c2\"><\/i>Na<sup>+<\/sup> ion<\/span>\n    <span><i style=\"background:#96a0b2\"><\/i>Mg<sup>2+<\/sup> ion<\/span>\n    <span><i style=\"background:#d63030; border-radius:50%\"><\/i>Delocalised electron<\/span>\n    <span><i style=\"background:rgba(220,60,60,0.25)\"><\/i>Electron sea<\/span>\n    <span><i style=\"background:#ffffff; border:1.5px solid rgba(28,36,75,0.75)\"><\/i>Unit cell<\/span>\n  <\/div>\n<\/div>\n<\/section>\n\n<p class=\"ols-cc-met-001\">&copy; Dr. Mohammed Al-Fatah &#8211; <a href=\"https:\/\/www.onlinelearningsystem.net\" target=\"_blank\" rel=\"noopener\">onlinelearningsystem.net<\/a><\/p>\n\n<script src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/JS\/metallic-bonding.js?v=20260926\"><\/script>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">3<\/div>\n          <h2>Why Delocalised Electrons Matter<\/h2>\n        <\/div>\n\n        <p>In a metal, delocalised electrons can move through the lattice. They are sometimes described as a <strong>sea of delocalised electrons<\/strong>.<\/p>\n        <p>This electron sea is attracted to many positive ions at the same time, helping to hold the whole giant lattice together rather than forming a small separate molecule.<\/p>\n        <p>The delocalised electrons also explain why metals can conduct electricity. When a potential difference is applied, the mobile electrons can move and carry charge through the structure.<\/p>\n\n        <div class=\"ols-equation-box\">\n          <p><strong>Metallic lattice model:<\/strong> positive metal ions + delocalised electrons &rarr; giant metallic lattice held by electrostatic attraction.<\/p>\n        <\/div>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Exam focus:<\/strong> Use the phrase <strong>delocalised electrons<\/strong>, not free electrons by itself. The electrons are free to move through the metallic lattice, but they are still part of the metal structure.<\/p>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Metal or Ionic Solid?<\/h2>\n<p>Complete the comparison of calcium metal with calcium oxide.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-224\" class=\"h5p-iframe\" data-content-id=\"224\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Metallic Bonding Drag: Calcium Metal Compared with Calcium Oxide\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card orange\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">4<\/div>\n          <h2>Metallic Bonding Strength Factors<\/h2>\n        <\/div>\n\n        <p>The strength of metallic bonding depends on how strongly the positive metal ions attract the delocalised electrons.<\/p>\n        <p>Three main factors are used in exam explanations: <strong>nuclear charge<\/strong>, the <strong>number of delocalised electrons per atom<\/strong> and the <strong>size of the metal ion<\/strong>.<\/p>\n\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Factor<\/th>\n                <th>Effect on metallic bonding<\/th>\n                <th>Exam wording<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Factor\"><strong>Number of protons<\/strong><\/td>\n                <td data-label=\"Effect on metallic bonding\">More protons means a higher nuclear charge, giving a stronger attraction to delocalised electrons.<\/td>\n                <td data-label=\"Exam wording\">More protons lead to a stronger attraction between positive ions and delocalised electrons.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Factor\"><strong>Number of delocalised electrons per atom<\/strong><\/td>\n                <td data-label=\"Effect on metallic bonding\">More delocalised electrons means a greater electron density available for attraction to the metal ions.<\/td>\n                <td data-label=\"Exam wording\">More delocalised electrons result in a stronger metallic bond.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Factor\"><strong>Size of the metal ion<\/strong><\/td>\n                <td data-label=\"Effect on metallic bonding\">Smaller ions allow the delocalised electrons to be attracted more strongly because the charge is closer.<\/td>\n                <td data-label=\"Exam wording\">Smaller ions produce a stronger attraction and therefore stronger metallic bonding.<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n\n        <div class=\"ols-zoom-card wide\">\n          <div class=\"ols-figure-card\">\n<div class=\"ols-figure-image\"><img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/fix-21.jpg\" alt=\"Three factors that make metallic bonding stronger, compared across sodium, magnesium and aluminium.\"><\/div>\n<div class=\"ols-figure-caption\"><p>Metallic bonding strength factors table showing protons, delocalised electrons and ion size<\/p><\/div>\n<\/div>\n          <div class=\"ols-zoom-card-caption\">\n            <p>Metallic bonding becomes stronger when the attraction between positive ions and delocalised electrons increases.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Rank the Metallic Bonding<\/h2>\n<p>Use ion charge, delocalised electrons per atom and ionic radius to put five metals in order.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-227\" class=\"h5p-iframe\" data-content-id=\"227\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Metallic Bonding Sort: Ranking Five Metals by Bond Strength\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card gold\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">5<\/div>\n          <h2>Comparing Metallic Bonding Strength<\/h2>\n        <\/div>\n\n        <p>Metallic bonding is often stronger when a metal atom contributes more outer-shell electrons to the delocalised electron sea.<\/p>\n        <p>For example, magnesium forms <strong>Mg<sup>2+<\/sup><\/strong> ions and contributes more delocalised electrons per atom than sodium, which forms <strong>Na<sup>+<\/sup><\/strong> ions. Aluminium forms <strong>Al<sup>3+<\/sup><\/strong> ions and contributes even more delocalised electrons per atom.<\/p>\n        <p>This is why exam answers often compare the charge on the metal ion, the number of delocalised electrons, and the strength of attraction within the lattice.<\/p>\n\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Metal<\/th>\n                <th>Ion commonly shown<\/th>\n                <th>Delocalised electrons per atom<\/th>\n                <th>Expected bonding strength trend<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Metal\"><strong>Sodium<\/strong><\/td>\n                <td data-label=\"Ion commonly shown\">Na<sup>+<\/sup><\/td>\n                <td data-label=\"Delocalised electrons per atom\">1<\/td>\n                <td data-label=\"Expected bonding strength trend\">Weaker than magnesium and aluminium, because fewer electrons are delocalised per atom.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Metal\"><strong>Magnesium<\/strong><\/td>\n                <td data-label=\"Ion commonly shown\">Mg<sup>2+<\/sup><\/td>\n                <td data-label=\"Delocalised electrons per atom\">2<\/td>\n                <td data-label=\"Expected bonding strength trend\">Stronger than sodium, because Mg<sup>2+<\/sup> attracts more delocalised electrons.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Metal\"><strong>Aluminium<\/strong><\/td>\n                <td data-label=\"Ion commonly shown\">Al<sup>3+<\/sup><\/td>\n                <td data-label=\"Delocalised electrons per atom\">3<\/td>\n                <td data-label=\"Expected bonding strength trend\">Usually stronger again, because Al<sup>3+<\/sup> has a higher charge and more delocalised electrons per atom.<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Accurate Statement or Common Mistake?<\/h2>\n<p>In each round, pick the one statement that is accurate.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-226\" class=\"h5p-iframe\" data-content-id=\"226\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Metallic Bonding Summary: Spot the Accurate Statement\"><\/iframe><\/div><\/div>\n<\/section>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Explain a Period 5 Contrast<\/h2>\n<p>Write a short explanation, then compare it with the mark points and the model answer.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-604\" class=\"h5p-iframe\" data-content-id=\"604\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Metallic Bonding Explain: Strontium Compared with Rubidium\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">6<\/div>\n          <h2>Common Exam Points<\/h2>\n        <\/div>\n\n        <p>Strong answers about metallic bonding must describe the correct particles and the correct force between them.<\/p>\n\n        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>Say positive metal ions, not atoms<\/h3>\n            <p>In the metallic lattice, the particles in fixed positions are positive metal ions, not neutral metal atoms.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Say delocalised electrons<\/h3>\n            <p>The outer-shell electrons are delocalised and can move through the structure. This is central to metallic bonding and electrical conductivity.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Use electrostatic attraction<\/h3>\n            <p>Metallic bonding is an electrostatic force of attraction between oppositely charged particles: positive metal ions and delocalised electrons.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Link strength to attraction<\/h3>\n            <p>Stronger metallic bonding means stronger attraction between the positive ions and the delocalised electron sea.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n\n      \n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">\u2713<\/div>\n          <h2>QuickSnap<\/h2>\n        <\/div>\n\n        <p>Metallic bonding is the strong electrostatic attraction between positive metal ions and delocalised electrons. Metals form giant metallic lattices, not molecules. The stronger the attraction between the ions and electron sea, the stronger the metallic bonding.<\/p>\n\n        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>Metallic bonding<\/h3>\n            <p>Electrostatic attraction between positive metal ions and delocalised electrons.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Giant metallic lattice<\/h3>\n            <p>A regular, closely packed arrangement of positive metal ions surrounded by delocalised electrons.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Delocalised electrons<\/h3>\n            <p>Outer-shell electrons that are free to move through the metal lattice.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Bonding strength<\/h3>\n            <p>Increases with stronger attraction, more delocalised electrons per atom, higher nuclear charge and smaller metal ion size.<\/p>\n        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36, 75, 0.30),\r\n          0 0 0 0 rgba(255, 255, 255, 0);\r\n      }\r\n    }\r\n\r\n    .ols-course-cta-ionic .ols-course-video-status {\r\n      margin: 14px 0 0;\r\n      text-align: center;\r\n      color: var(--grey-text);\r\n      font-size: 13px;\r\n      line-height: 1.5;\r\n      font-weight: 500;\r\n    }\r\n\r\n    .ols-course-cta-ionic .ols-course-cta-bottom {\r\n      display: flex;\r\n      justify-content: center;\r\n      padding-top: 22px;\r\n      border-top: 1px solid var(--border);\r\n    }\r\n\r\n    .ols-course-cta-ionic .ols-course-button {\r\n      display: inline-flex;\r\n      align-items: center;\r\n      justify-content: center;\r\n      padding: 15px 28px;\r\n      border-radius: 999px;\r\n      background: var(--navy);\r\n      color: #ffffff;\r\n      text-decoration: none;\r\n      font-size: 16px;\r\n      line-height: 1.2;\r\n      font-weight: 800;\r\n      box-shadow: 0 12px 26px rgba(28, 36, 75, 0.18);\r\n      transition:\r\n        transform 0.2s ease,\r\n        background 0.2s ease,\r\n        box-shadow 0.2s ease;\r\n    }\r\n\r\n    .ols-course-cta-ionic .ols-course-button:hover {\r\n      transform: translateY(-2px);\r\n      background: var(--blue);\r\n      color: #ffffff;\r\n      box-shadow: 0 16px 32px rgba(37, 99, 235, 0.24);\r\n    }\r\n\r\n    .ols-course-cta-ionic .ols-course-button-top {\r\n      flex-shrink: 0;\r\n      padding: 12px 22px;\r\n      font-size: 15px;\r\n    }\r\n\r\n    @media (max-width: 900px) {\r\n      .ols-course-cta-ionic .ols-course-cta-top {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-cta-image-link {\r\n        max-width: 520px;\r\n        margin: 0 auto;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-cta-intro-stats {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-animation-frame-shell {\r\n        height: 520px;\r\n      }\r\n    }\r\n\r\n    @media (max-width: 760px) {\r\n      .ols-course-cta-ionic {\r\n        margin: 26px 0 22px;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-cta-card {\r\n        padding: 20px;\r\n        border-radius: 24px;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-cta-header-row {\r\n        align-items: stretch;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-button-top {\r\n        width: 100%;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-cta-stats,\r\n      .ols-course-cta-ionic .ols-course-cta-features {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-animation-wrap {\r\n        padding: 0;\r\n        border-radius: 0;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-animation-frame-shell {\r\n        height: 420px;\r\n        border-radius: 18px;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-animation-play-circle {\r\n        width: 76px;\r\n        height: 76px;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-animation-play-icon {\r\n        border-top-width: 14px;\r\n        border-bottom-width: 14px;\r\n        border-left-width: 22px;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-animation-pause-button {\r\n        left: 12px;\r\n        bottom: 12px;\r\n        min-width: 84px;\r\n        padding: 9px 14px;\r\n        font-size: 13px;\r\n      }\r\n\r\n      .ols-course-cta-ionic .ols-course-button {\r\n        width: 100%;\r\n      }\r\n    }\r\n  <\/style>\r\n\r\n  <div class=\"ols-course-cta-card\">\r\n\r\n    <div class=\"ols-course-cta-top\">\r\n\r\n      <a class=\"ols-course-cta-image-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/product\/ionic-and-metallic-bonding-topic-3-cambridge-international\/\" aria-label=\"Open the Cambridge International AS and A Level Chemistry Topic 3 Ionic and Metallic Bonding course page\">\r\n\r\n        <div class=\"ols-course-cta-image\">\r\n          <img decoding=\"async\"\r\n            src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/cambridge-international-a-level-chemistry-topic-3-ionic-metallic-bonding-interactive-course-banner.jpg\"\r\n            alt=\"Cambridge International AS and A Level Chemistry Topic 3 Ionic and Metallic Bonding interactive course banner\"\r\n          >\r\n        <\/div>\r\n\r\n      <\/a>\r\n\r\n      <div class=\"ols-course-cta-content\">\r\n\r\n        <div class=\"ols-course-cta-header-row\">\r\n\r\n          <div class=\"ols-course-cta-kicker\">\r\n            Cambridge 9701 | Topic 3 Course\r\n          <\/div>\r\n\r\n          <a class=\"ols-course-button ols-course-button-top\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/product\/ionic-and-metallic-bonding-topic-3-cambridge-international\/\">\r\n            View Course\r\n          <\/a>\r\n\r\n        <\/div>\r\n\r\n        <h2>\r\n          Master Ionic and Metallic Bonding for Cambridge International AS &amp; 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 3 Ionic and Metallic Bonding course. The guided video lessons are ready now; the Cambridge International MCQ bank, teacher-marked short-answer questions and KASP spec-point report are being written, and the course opens for enrolment as soon as they are complete.\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>Recorded lessons<\/span>\n          <strong>Coming soon<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Video lessons<\/span>\n          <strong>Coming soon<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>MCQ practice<\/span>\n          <strong>Coming soon<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>SAQ practice<\/span>\n          <strong>Coming soon<\/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 the chemistry and exam technique 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 the full Topic 3 specification 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=\"olsCourseAnimationFrame001\"\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=\"olsCourseAnimationStart001\"\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=\"olsCourseAnimationPause001\"\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:\/\/www.onlinelearningsystem.net\/xyz\/product\/ionic-and-metallic-bonding-topic-3-cambridge-international\/\">\r\n        View Ionic and Metallic Bonding Course\r\n      <\/a>\r\n\r\n    <\/div>\r\n\r\n  <\/div>\r\n\r\n  <template id=\"olsCourseAnimationTemplate001\">\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  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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\">Some ionic radii are shown.<\/p>\r\n\r\n            <table class=\"mcq-ionic-table\">\r\n              <thead>\r\n                <tr>\r\n                  <th>Ion<\/th>\r\n                  <th>Ionic radius \/ nm<\/th>\r\n                <\/tr>\r\n              <\/thead>\r\n              <tbody>\r\n                <tr><td>Na<sup>+<\/sup><\/td><td>0.102<\/td><\/tr>\r\n                <tr><td>K<sup>+<\/sup><\/td><td>0.138<\/td><\/tr>\r\n                <tr><td>F<sup>\u2212<\/sup><\/td><td>0.133<\/td><\/tr>\r\n                <tr><td>Cl<sup>\u2212<\/sup><\/td><td>0.180<\/td><\/tr>\r\n              <\/tbody>\r\n            <\/table>\r\n\r\n            <p class=\"mcq-question-main\">Which compound has the strongest ionic bonding?<\/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\">sodium chloride<\/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\">potassium chloride<\/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\">sodium fluoride<\/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\">potassium fluoride<\/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; Melting temperature depends on the strength of metallic bonding.<br>\r\n              Explain why the metallic bonding in magnesium is much stronger than that in sodium.\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\" 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the ions can get closer together.\\n\"+\r\n\"\u2022 Smaller ions \u2192 stronger electrostatic attraction \u2192 stronger ionic lattice.\\n\"+\r\n\"\u2022 Na\u207a (0.102 nm) is smaller than K\u207a (0.138 nm).\\n\"+\r\n\"\u2022 F\u207b (0.133 nm) is smaller than Cl\u207b (0.180 nm).\\n\\n\"+\r\n\"Therefore, the strongest ionic bonding occurs in the compound formed by the smallest cation and the smallest anion \u2192 sodium fluoride (NaF).\\n\\n\"+\r\n\"The correct answer is: sodium fluoride\";\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 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Melting temperature is a result of bonding strength, not the cause of it.\\n\\n\"+\r\n\"In metallic bonding, positive metal ions are attracted to a sea of delocalised electrons. The strength of this attraction depends on the charge of the ions and the number of delocalised electrons.\\n\\n\"+\r\n\"Magnesium forms Mg\u00b2\u207a ions and contributes two delocalised electrons per atom, whereas sodium forms Na\u207a ions and contributes only one electron. This results in a stronger electrostatic attraction in magnesium. Additionally, Mg\u00b2\u207a ions have a higher charge density than Na\u207a ions, further strengthening the metallic bonding.\\n\\n\"+\r\n\"Next time, include:\\n\"+\r\n\"\u2022 Ion charge: magnesium forms Mg\u00b2\u207a, sodium forms Na\u207a \u2713\\n\"+\r\n\"\u2022 Delocalised electrons: magnesium provides more electrons to the sea \u2713\\n\"+\r\n\"\u2022 Charge density: smaller, more highly charged ions create stronger attraction \u2713\\n\\n\"+\r\n\"You were close. 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They can move through the metallic lattice.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>What makes metallic bonding stronger?<\/h3>\n            <p>Metallic bonding becomes stronger when there is a stronger attraction between positive ions and delocalised electrons. This is affected by nuclear charge, ion size and the number of delocalised electrons per atom.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Why do metals conduct electricity?<\/h3>\n            <p>Metals conduct electricity because their delocalised electrons are mobile and can carry charge through the lattice when a potential difference is applied.<\/p>\n          <\/div>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-related-card\">\n        <h2>Related Topics<\/h2>\n        <p>Use these pages to connect metallic bonding with ionic bonding, polarisation and covalent bonding in Topic 3.<\/p>\n        <div class=\"ols-related-grid\">\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/metallic-bonding\/physical-properties-of-metals\/\">Physical Properties of Metals<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/ionic-bonding\/nature-of-ionic-bonding\/\">Nature of Ionic Bonding<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/ionic-bonding\/polarisation-of-ions\/\">Polarisation of Ions<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/ionic-bonding\/physical-properties-of-ionic-compounds\/\">Physical Properties of Ionic Compounds<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/nature-of-covalent-bonding\/\">Nature of Covalent Bonding<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/\">Topic 3 Chemical Bonding<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card\">\n        <p><strong>Copyright notice:<\/strong> This OLS revision page is written for Online Learning System by <strong>Dr. Mohammed Al-Fatah<\/strong>. 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