{"id":4596,"date":"2026-05-30T06:13:12","date_gmt":"2026-05-30T05:13:12","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/metallic-bonding-and-structure\/"},"modified":"2026-06-01T11:16:50","modified_gmt":"2026-06-01T10:16:50","slug":"metallic-bonding-and-structure","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/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: 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#ffffff; box-shadow: var(--inner-shadow); }\n      .ols-table td { border-bottom: 1px solid var(--border); padding: 14px 16px; overflow-wrap: anywhere; }\n      .ols-table td:last-child { border-bottom: none; }\n      .ols-table td::before { content: attr(data-label); display: block; margin-bottom: 6px; font-size: 13px; font-weight: 700; color: var(--blue); }\n      .ols-author { align-items: flex-start; padding: 22px 18px; border-radius: 22px; }\n      .ols-author-avatar-img { width: 72px; height: 72px; }\n      .ols-author-title { font-size: 24px; }\n      .ols-author-description { font-size: 15px; }\n      .ols-infographic-full { margin: 0 0 26px; }\n      .ols-infographic-full-frame { border-radius: 18px; padding: 0; }\n      .ols-zoomable-img:hover { transform: none; box-shadow: none; }\n    }\n  <\/style>\n\n    <aside class=\"ols-sidebar\">\r\n  <div class=\"ols-sidebar-header\">\r\n    <h3>Revision Notes<\/h3>\r\n    <p>A Level Chemistry<\/p>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Topic 2 Bonding and Structure<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/\">Ionic Bonding<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/nature-of-ionic-bonding\/\">Nature of Ionic Bonding<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/polarisation-of-ions\/\">Polarisation of Ions<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/physical-properties-of-ionic-compounds\/\">Physical Properties of Ionic Compounds<\/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-2-bonding-and-structure\/covalent-bonding\/\">Covalent Bonding<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/nature-of-covalent-bonding\/\">Nature of Covalent Bonding<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/dative-covalent-bonding\/\">Dative Covalent Bonding<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/electronegativity\/\">Electronegativity<\/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-2-bonding-and-structure\/shapes-of-molecules\/\">Shapes of Molecules<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/linear\/\">Linear<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-planar\/\">Trigonal Planar<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/\">Tetrahedral<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/\">Trigonal Pyramidal<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/bent\/\">Bent<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-bipyramidal\/\">Trigonal Bipyramidal<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/octahedral\/\">Octahedral<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/square-planar\/\">Square Planar<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/square-pyramidal\/\">Square Pyramidal<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/distorted-t\/\">Distorted T<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/seesaw\/\">SeeSaw<\/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-2-bonding-and-structure\/polar-molecules\/\">Polar 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-2-bonding-and-structure\/metallic-bonding\/\">Metallic Bonding<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/metallic-bonding-and-structure\/\">Metallic Bonding and Structure<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/physical-properties-of-metals\/\">Physical Properties of Metals<\/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-2-bonding-and-structure\/intermolecular-forces\/\">Intermolecular Forces<\/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-2-bonding-and-structure\/structure-types\/\">Structure Types<\/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-3-redox-i\/\">Redox 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\/\">Inorganic Chemistry &amp; The Periodic Table<\/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\/\">Formulae, Equations &amp; Amounts<\/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      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href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/\">A Level Chemistry<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/\">Edexcel<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/\">Topic 2 Bonding and Structure<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/\">Metallic Bonding<\/a> \/\n        <span>Metallic Bonding &amp; 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\">Unit: Paper 1<\/div>\n          <div class=\"ols-badge\">Topic 2: Bonding and Structure<\/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\">\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      <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\n      <section id=\"ols-na-metallic-unit-cell-card\" class=\"ols-na-metallic-unit-cell-card\">\n  <style>\n    #ols-na-metallic-unit-cell-card {\n      --ols-navy: #1C244B;\n      --ols-gold: #c9973a;\n      --ols-blue: #1f7ae0;\n      --ols-red: #c81e1e;\n      --ols-soft-blue: #eef6ff;\n      --ols-border: rgba(28, 36, 75, 0.14);\n      --ols-shadow: 0 14px 34px rgba(28, 36, 75, 0.12);\n      font-family: Poppins, Arial, sans-serif;\n      color: var(--ols-navy);\n      width: 100%;\n      margin: 28px auto;\n    }\n\n    #ols-na-metallic-unit-cell-card * {\n      box-sizing: border-box;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-model-card {\n      width: 100%;\n      background: linear-gradient(180deg, #ffffff 0%, #f8fbff 100%);\n      border: 1px solid var(--ols-border);\n      border-radius: 28px;\n      box-shadow: var(--ols-shadow);\n      overflow: hidden;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-model-header {\n      padding: 24px 26px 16px;\n      border-bottom: 1px solid rgba(28, 36, 75, 0.08);\n      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1.55;\n      font-weight: 300;\n      color: rgba(28, 36, 75, 0.82);\n      max-width: 980px;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-viewer-wrap {\n      position: relative;\n      width: 100%;\n      height: 560px;\n      background:\n        radial-gradient(circle at center, rgba(200, 30, 30, 0.055), transparent 38%),\n        linear-gradient(180deg, #ffffff 0%, #f7f9fc 100%);\n      overflow: hidden;\n    }\n\n    #ols-na-metallic-unit-cell-card #olsNaMetallicUnitCellViewer {\n      width: 100%;\n      height: 100%;\n      display: block;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-viewer-badge {\n      position: absolute;\n      top: 16px;\n      right: 16px;\n      background: rgba(255, 255, 255, 0.92);\n      color: var(--ols-navy);\n      padding: 8px 12px;\n      border-radius: 12px;\n      font-size: 13px;\n      font-weight: 600;\n      box-shadow: 0 6px 18px rgba(28, 36, 75, 0.14);\n      border: 1px solid rgba(28, 36, 75, 0.08);\n      pointer-events: none;\n      z-index: 4;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-controls {\n      display: flex;\n      flex-wrap: wrap;\n      gap: 10px;\n      padding: 16px 18px;\n      background: #ffffff;\n      border-top: 1px solid rgba(28, 36, 75, 0.08);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-btn {\n      appearance: none;\n      border: 1px solid rgba(28, 36, 75, 0.14);\n      background: #ffffff;\n      color: var(--ols-navy);\n      border-radius: 999px;\n      padding: 10px 15px;\n      font-family: Poppins, Arial, sans-serif;\n      font-size: 14px;\n      font-weight: 600;\n      cursor: pointer;\n      transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-btn:hover {\n      transform: translateY(-2px);\n      box-shadow: 0 8px 20px rgba(28, 36, 75, 0.12);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-btn.is-active {\n      background: var(--ols-navy);\n      color: #ffffff;\n      border-color: var(--ols-navy);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-btn.ols-red {\n      background: var(--ols-red);\n      color: #ffffff;\n      border-color: var(--ols-red);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-model-legend {\n      display: grid;\n      grid-template-columns: repeat(3, minmax(0, 1fr));\n      gap: 12px;\n      padding: 16px 18px;\n      background: #ffffff;\n      border-top: 1px solid rgba(28, 36, 75, 0.08);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-legend-item {\n      display: flex;\n      align-items: center;\n      gap: 10px;\n      padding: 12px 14px;\n      border-radius: 16px;\n      background: #f8fbff;\n      border: 1px solid rgba(28, 36, 75, 0.1);\n      font-size: 14px;\n      line-height: 1.45;\n      font-weight: 400;\n      color: rgba(28, 36, 75, 0.84);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-legend-dot {\n      width: 15px;\n      height: 15px;\n      border-radius: 50%;\n      flex: 0 0 auto;\n      box-shadow: 0 3px 8px rgba(28, 36, 75, 0.16);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-legend-dot.na {\n      background: #dfe3ea;\n      border: 1px solid rgba(28, 36, 75, 0.18);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-legend-dot.electron {\n      background: #c81e1e;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-legend-dot.cloud {\n      background: rgba(200, 30, 30, 0.35);\n      border: 1px solid rgba(200, 30, 30, 0.45);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-explanation {\n      padding: 22px 26px 26px;\n      background: #ffffff;\n      border-top: 1px solid rgba(28, 36, 75, 0.08);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-explanation-grid {\n      display: grid;\n      grid-template-columns: repeat(3, minmax(0, 1fr));\n      gap: 14px;\n      margin-top: 16px;\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-info-box {\n      border-radius: 18px;\n      padding: 16px;\n      background: #f8fbff;\n      border: 1px solid rgba(28, 36, 75, 0.1);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-info-box strong {\n      display: block;\n      font-size: 15px;\n      margin-bottom: 6px;\n      color: var(--ols-navy);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-info-box span {\n      display: block;\n      font-size: 14px;\n      line-height: 1.55;\n      font-weight: 300;\n      color: rgba(28, 36, 75, 0.8);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-key-message {\n      margin: 0;\n      padding: 16px 18px;\n      border-radius: 18px;\n      background: var(--ols-soft-blue);\n      border: 1px solid rgba(31, 122, 224, 0.14);\n      font-size: 16px;\n      line-height: 1.65;\n      font-weight: 300;\n      color: rgba(28, 36, 75, 0.88);\n    }\n\n    #ols-na-metallic-unit-cell-card .ols-key-message strong {\n      font-weight: 700;\n      color: var(--ols-navy);\n    }\n\n    @media (max-width: 820px) {\n      #ols-na-metallic-unit-cell-card .ols-viewer-wrap {\n        height: 470px;\n      }\n\n      #ols-na-metallic-unit-cell-card .ols-explanation-grid,\n      #ols-na-metallic-unit-cell-card .ols-model-legend {\n        grid-template-columns: 1fr;\n      }\n\n      #ols-na-metallic-unit-cell-card .ols-viewer-badge {\n        top: 12px;\n        right: 12px;\n        font-size: 12px;\n      }\n    }\n\n    @media (max-width: 520px) {\n      #ols-na-metallic-unit-cell-card .ols-model-header,\n      #ols-na-metallic-unit-cell-card .ols-explanation {\n        padding-left: 18px;\n        padding-right: 18px;\n      }\n\n      #ols-na-metallic-unit-cell-card .ols-viewer-wrap {\n        height: 420px;\n      }\n\n      #ols-na-metallic-unit-cell-card .ols-controls,\n      #ols-na-metallic-unit-cell-card .ols-model-legend {\n        padding: 14px;\n      }\n\n      #ols-na-metallic-unit-cell-card .ols-btn {\n        width: 100%;\n      }\n    }\n  <\/style>\n\n  <div class=\"ols-model-card\">\n    <div class=\"ols-model-header\">\n      <div class=\"ols-pill\">3D metallic bonding model<\/div>\n      <h2 class=\"ols-model-title\">Sodium metallic bonding in one repeat unit cell<\/h2>\n      <p class=\"ols-model-subtitle\">\n        A centred cubic-style model showing 8 corner Na\u207a ions and 1 central Na\u207a ion fixed in position. Nine small red electrons move through the unit cell, with a toggleable red electron cloud to show that the electrons are better represented as delocalised electron density rather than fixed particles.\n      <\/p>\n    <\/div>\n\n    <div class=\"ols-viewer-wrap\">\n      <div id=\"olsNaMetallicUnitCellViewer\"><\/div>\n      <div class=\"ols-viewer-badge\">Drag to rotate \u2022 Scroll to zoom<\/div>\n    <\/div>\n\n    <div class=\"ols-controls\">\n      <button type=\"button\" class=\"ols-btn is-active\" id=\"olsNaMetalRotateBtn\">Pause rotation<\/button>\n      <button type=\"button\" class=\"ols-btn ols-red\" id=\"olsNaElectronParticlesBtn\">Hide electron particles<\/button>\n      <button type=\"button\" class=\"ols-btn ols-red\" id=\"olsNaElectronCloudBtn\">Hide electron cloud<\/button>\n      <button type=\"button\" class=\"ols-btn\" id=\"olsNaElectronMotionBtn\">Pause electron motion<\/button>\n      <button type=\"button\" class=\"ols-btn\" id=\"olsNaMetalResetBtn\">Reset view<\/button>\n    <\/div>\n\n    <div class=\"ols-model-legend\" aria-label=\"Metallic bonding model legend\">\n      <div class=\"ols-legend-item\">\n        <span class=\"ols-legend-dot na\"><\/span>\n        <span><strong>Na\u207a ions:<\/strong> 8 corner ions and 1 central ion fixed in the unit cell.<\/span>\n      <\/div>\n\n      <div class=\"ols-legend-item\">\n        <span class=\"ols-legend-dot electron\"><\/span>\n        <span><strong>Red particles:<\/strong> 9 moving electrons, one simplified electron per displayed Na\u207a ion.<\/span>\n      <\/div>\n\n      <div class=\"ols-legend-item\">\n        <span class=\"ols-legend-dot cloud\"><\/span>\n        <span><strong>Red cloud:<\/strong> delocalised electron density spread through the whole unit cell.<\/span>\n      <\/div>\n    <\/div>\n\n    <div class=\"ols-explanation\">\n      <p class=\"ols-key-message\">\n        <strong>Key idea:<\/strong> metallic bonding in sodium can be modelled as fixed <strong>Na\u207a ions<\/strong> in a regular lattice surrounded by <strong>delocalised electrons<\/strong>. The small red moving particles are a simplified teaching model. The red cloud is the better model, because the electrons are spread out as electron density throughout the metallic lattice.\n      <\/p>\n\n      <div class=\"ols-explanation-grid\">\n        <div class=\"ols-info-box\">\n          <strong>Na\u207a ions<\/strong>\n          <span>The large silver\/gold spheres represent positive sodium ions fixed at lattice positions.<\/span>\n        <\/div>\n\n        <div class=\"ols-info-box\">\n          <strong>Moving electrons<\/strong>\n          <span>The 9 small red particles show one simplified electron per displayed Na\u207a ion moving through the unit cell.<\/span>\n        <\/div>\n\n        <div class=\"ols-info-box\">\n          <strong>Electron cloud<\/strong>\n          <span>The red dot cloud represents delocalised electron density spread across the whole metallic structure.<\/span>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/div>\n\n  <script>\n    (function () {\n      const CARD_ID = \"ols-na-metallic-unit-cell-card\";\n      const VIEWER_ID = \"olsNaMetallicUnitCellViewer\";\n\n      function loadScript(src) {\n        return new Promise(function (resolve, reject) {\n          if (src.indexOf(\"three.min.js\") !== -1) {\n            if (window.THREE) {\n              resolve();\n              return;\n            }\n          }\n\n          if (src.indexOf(\"OrbitControls.js\") !== -1) {\n            if (window.THREE) {\n              if (THREE.OrbitControls) {\n                resolve();\n                return;\n              }\n            }\n          }\n\n          const existing = document.querySelector('script[src=\"' + src + '\"]');\n          if (existing) {\n            existing.addEventListener(\"load\", resolve);\n            existing.addEventListener(\"error\", reject);\n\n            if (existing.dataset.loaded === \"true\") {\n              resolve();\n            }\n            return;\n          }\n\n          const script = document.createElement(\"script\");\n          script.src = 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= false;\n\n            for (let n = 0; n < ionPositions.length; n++) {\n              const distance = p.distanceTo(ionPositions[n]);\n              if (distance < 0.34) {\n                tooCloseToIon = true;\n                break;\n              }\n            }\n\n            if (tooCloseToIon) {\n              continue;\n            }\n\n            positions[i * 3] = p.x;\n            positions[i * 3 + 1] = p.y;\n            positions[i * 3 + 2] = p.z;\n\n            const centreFactor = Math.max(0, 1 - p.length() \/ (cloudSize * 0.88));\n            const c = paleRed.clone().lerp(midRed, 0.46).lerp(deepRed, centreFactor * 0.46);\n\n            colors[i * 3] = c.r;\n            colors[i * 3 + 1] = c.g;\n            colors[i * 3 + 2] = c.b;\n\n            i++;\n          }\n\n          const geometry = new THREE.BufferGeometry();\n          geometry.setAttribute(\"position\", new THREE.BufferAttribute(positions, 3));\n          geometry.setAttribute(\"color\", new THREE.BufferAttribute(colors, 3));\n\n          const material = new THREE.PointsMaterial({\n            size: 0.034,\n            vertexColors: true,\n            transparent: true,\n            opacity: 0.54,\n            depthWrite: false,\n            blending: THREE.NormalBlending\n          });\n\n          return new THREE.Points(geometry, material);\n        }\n\n        function createUnitCellFrame(sizeValue) {\n          const group = new THREE.Group();\n          const h = sizeValue \/ 2;\n\n          const points = [\n            [-h, -h, -h], [h, -h, -h],\n            [h, -h, -h], [h, h, -h],\n            [h, h, -h], [-h, h, -h],\n            [-h, h, -h], [-h, -h, -h],\n\n            [-h, -h, h], [h, -h, h],\n            [h, -h, h], [h, h, h],\n            [h, h, h], [-h, h, h],\n            [-h, h, h], [-h, -h, h],\n\n            [-h, -h, -h], [-h, -h, h],\n            [h, -h, -h], [h, -h, h],\n            [h, h, -h], [h, h, h],\n            [-h, h, -h], [-h, h, h]\n          ];\n\n          const vertices = [];\n          points.forEach(function (p) {\n            vertices.push(p[0], p[1], p[2]);\n          });\n\n          const geometry = new THREE.BufferGeometry();\n          geometry.setAttribute(\"position\", new THREE.Float32BufferAttribute(vertices, 3));\n\n          const material = new THREE.LineBasicMaterial({\n            color: 0xc9973a,\n            transparent: true,\n            opacity: 0.96\n          });\n\n          const lines = new THREE.LineSegments(geometry, material);\n          group.add(lines);\n\n          const transparentCube = new THREE.Mesh(\n            new THREE.BoxGeometry(sizeValue, sizeValue, sizeValue),\n            new THREE.MeshPhysicalMaterial({\n              color: 0xc9973a,\n              transparent: true,\n              opacity: 0.045,\n              metalness: 0,\n              roughness: 0.4,\n              depthWrite: false\n            })\n          );\n\n          group.add(transparentCube);\n\n          return group;\n        }\n\n        function createElectronGlow() {\n          const canvas = document.createElement(\"canvas\");\n          canvas.width = 128;\n          canvas.height = 128;\n          const ctx = canvas.getContext(\"2d\");\n\n          const gradient = ctx.createRadialGradient(64, 64, 2, 64, 64, 62);\n          gradient.addColorStop(0, \"rgba(255, 255, 255, 0.62)\");\n          gradient.addColorStop(0.35, \"rgba(255, 70, 70, 0.34)\");\n          gradient.addColorStop(1, \"rgba(255, 70, 70, 0)\");\n          ctx.fillStyle = gradient;\n          ctx.fillRect(0, 0, 128, 128);\n\n          const texture = new THREE.CanvasTexture(canvas);\n          const material = new THREE.SpriteMaterial({\n            map: texture,\n            color: 0xc81e1e,\n            transparent: true,\n            depthWrite: false\n          });\n\n          const sprite = new THREE.Sprite(material);\n          sprite.scale.set(0.42, 0.42, 1);\n          return sprite;\n        }\n\n        function addGlow(parent, position, scale, color, opacity) {\n          const canvas = document.createElement(\"canvas\");\n          canvas.width = 128;\n          canvas.height = 128;\n          const ctx = canvas.getContext(\"2d\");\n          const gradient = ctx.createRadialGradient(64, 64, 2, 64, 64, 62);\n          gradient.addColorStop(0, \"rgba(255,255,255,\" + opacity + \")\");\n          gradient.addColorStop(0.42, \"rgba(150,205,255,\" + (opacity * 0.55) + \")\");\n          gradient.addColorStop(1, \"rgba(255,255,255,0)\");\n          ctx.fillStyle = gradient;\n          ctx.fillRect(0, 0, 128, 128);\n\n          const texture = new THREE.CanvasTexture(canvas);\n          const material = new THREE.SpriteMaterial({\n            map: texture,\n            color: color,\n            transparent: true,\n            depthWrite: false\n          });\n\n          const sprite = new THREE.Sprite(material);\n          sprite.position.copy(position);\n          sprite.scale.set(scale * 2.2, scale * 2.2, 1);\n          parent.add(sprite);\n        }\n\n        function addTextSprite(parent, text, position, fontSize, color, scale) {\n          const canvas = document.createElement(\"canvas\");\n          canvas.width = 860;\n          canvas.height = 256;\n          const ctx = canvas.getContext(\"2d\");\n\n          ctx.clearRect(0, 0, canvas.width, canvas.height);\n          ctx.font = \"700 \" + fontSize + \"px Arial, sans-serif\";\n          ctx.textAlign = \"center\";\n          ctx.textBaseline = \"middle\";\n\n          ctx.lineWidth = 10;\n          ctx.strokeStyle = \"rgba(255,255,255,0.94)\";\n          ctx.strokeText(text, canvas.width \/ 2, canvas.height \/ 2);\n\n          ctx.fillStyle = color;\n          ctx.fillText(text, canvas.width \/ 2, canvas.height \/ 2);\n\n          const texture = new THREE.CanvasTexture(canvas);\n          const material = new THREE.SpriteMaterial({\n            map: texture,\n            transparent: true,\n            depthTest: false\n          });\n\n          const sprite = new THREE.Sprite(material);\n          sprite.position.copy(position);\n          sprite.scale.set(1.48 * scale, 0.59 * scale, 1);\n          parent.add(sprite);\n        }\n\n        function updateElectronMovement() {\n          if (!electronMotion) {\n            return;\n          }\n\n          electrons.forEach(function (electron) {\n            electron.mesh.position.add(electron.velocity);\n\n            if (electron.mesh.position.x > half - 0.18) {\n              electron.mesh.position.x = half - 0.18;\n              electron.velocity.x *= -1;\n            }\n\n            if (electron.mesh.position.x < -half + 0.18) {\n              electron.mesh.position.x = -half + 0.18;\n              electron.velocity.x *= -1;\n            }\n\n            if (electron.mesh.position.y > half - 0.18) {\n              electron.mesh.position.y = half - 0.18;\n              electron.velocity.y *= -1;\n            }\n\n            if (electron.mesh.position.y < -half + 0.18) {\n              electron.mesh.position.y = -half + 0.18;\n              electron.velocity.y *= -1;\n            }\n\n            if (electron.mesh.position.z > half - 0.18) {\n              electron.mesh.position.z = half - 0.18;\n              electron.velocity.z *= -1;\n            }\n\n            if (electron.mesh.position.z < -half + 0.18) {\n              electron.mesh.position.z = -half + 0.18;\n              electron.velocity.z *= -1;\n            }\n\n            for (let n = 0; n < ionPositions.length; n++) {\n              const distanceToIon = electron.mesh.position.distanceTo(ionPositions[n]);\n\n              if (distanceToIon < 0.42) {\n                const away = electron.mesh.position.clone().sub(ionPositions[n]).normalize();\n                electron.mesh.position.copy(ionPositions[n].clone().add(away.multiplyScalar(0.42)));\n                electron.velocity.reflect(away);\n              }\n            }\n\n            electron.glow.position.copy(electron.mesh.position);\n          });\n        }\n\n        function setElectronParticlesVisibility(value) {\n          electronParticlesVisible = value;\n          electronParticleGroup.visible = electronParticlesVisible;\n\n          if (electronParticlesVisible) {\n            electronParticlesBtn.textContent = \"Hide electron particles\";\n            electronParticlesBtn.classList.add(\"ols-red\");\n          } else {\n            electronParticlesBtn.textContent = \"Show electron particles\";\n            electronParticlesBtn.classList.remove(\"ols-red\");\n          }\n        }\n\n        function setElectronCloudVisibility(value) {\n          electronCloudVisible = value;\n          electronCloudGroup.visible = electronCloudVisible;\n\n          if (electronCloudVisible) {\n            electronCloudBtn.textContent = \"Hide electron cloud\";\n            electronCloudBtn.classList.add(\"ols-red\");\n          } else {\n            electronCloudBtn.textContent = \"Show electron cloud\";\n            electronCloudBtn.classList.remove(\"ols-red\");\n          }\n        }\n\n        function setElectronMotion(value) {\n          electronMotion = value;\n\n          if (electronMotion) {\n            electronMotionBtn.textContent = \"Pause electron motion\";\n            electronMotionBtn.classList.remove(\"is-active\");\n          } else {\n            electronMotionBtn.textContent = \"Resume electron motion\";\n            electronMotionBtn.classList.add(\"is-active\");\n          }\n        }\n\n        function resetView() {\n          camera.position.set(5.0, 4.2, 7.2);\n          controls.target.set(0, 0, 0);\n          controls.update();\n          root.rotation.set(0, 0, 0);\n\n          electronStartPositions.forEach(function (pos, index) {\n            electrons[index].mesh.position.copy(pos);\n            electrons[index].glow.position.copy(pos);\n          });\n        }\n\n        rotateBtn.addEventListener(\"click\", function () {\n          autoRotate = !autoRotate;\n          rotateBtn.classList.toggle(\"is-active\", autoRotate);\n\n          if (autoRotate) {\n            rotateBtn.textContent = \"Pause rotation\";\n          } else {\n            rotateBtn.textContent = \"Resume rotation\";\n          }\n        });\n\n        electronParticlesBtn.addEventListener(\"click\", function () {\n          setElectronParticlesVisibility(!electronParticlesVisible);\n        });\n\n        electronCloudBtn.addEventListener(\"click\", function () {\n          setElectronCloudVisibility(!electronCloudVisible);\n        });\n\n        electronMotionBtn.addEventListener(\"click\", function () {\n          setElectronMotion(!electronMotion);\n        });\n\n        resetBtn.addEventListener(\"click\", resetView);\n\n        const observer = new IntersectionObserver(function (entries) {\n          entries.forEach(function (entry) {\n            isVisible = entry.isIntersecting;\n          });\n        }, { threshold: 0.18 });\n\n        observer.observe(card);\n\n        function onResize() {\n          const width = container.clientWidth;\n          const height = container.clientHeight;\n          camera.aspect = width \/ height;\n          camera.updateProjectionMatrix();\n          renderer.setSize(width, height);\n        }\n\n        window.addEventListener(\"resize\", onResize);\n\n        function animate() {\n          requestAnimationFrame(animate);\n\n          if (isVisible) {\n            if (autoRotate) {\n              root.rotation.y += 0.0032;\n            }\n\n            updateElectronMovement();\n          }\n\n          controls.update();\n          renderer.render(scene, camera);\n        }\n\n        animate();\n      }\n\n      document.addEventListener(\"DOMContentLoaded\", function () {\n        loadScript(\"https:\/\/cdnjs.cloudflare.com\/ajax\/libs\/three.js\/r128\/three.min.js\")\n          .then(function () {\n            return loadScript(\"https:\/\/cdn.jsdelivr.net\/npm\/three@0.128.0\/examples\/js\/controls\/OrbitControls.js\");\n          })\n          .then(function () {\n            initNaMetallicUnitCellModel();\n          })\n          .catch(function (error) {\n            console.error(\"Na metallic unit cell model failed to load:\", error);\n          });\n      });\n    })();\n  <\/script>\n<\/section>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">3<\/div>\n          <h2>Why 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\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-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-2.webp\" alt=\"Metallic bonding strength factors table showing protons, delocalised electrons and ion size\">\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\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\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      <section class=\"ols-h5p-card\">\n        <h2>Check Your Understanding<\/h2>\n        <p>Use these short activities to check metallic bonding, giant metallic lattice structure, delocalised electrons and metallic bonding strength factors.<\/p>\n\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=\"T3.2.4.1 Drag: Metallic Bonding Key Concepts\"><\/iframe><\/div><\/div>\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=\"T3.2.4.2 MCQ: Definition of Metallic Bonding\"><\/iframe><\/div><\/div>\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=\"T3.2.4.3 MCQ: Giant Metallic Lattice Structure\"><\/iframe><\/div><\/div>\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=\"T3.2.4.4 MCQ: Metallic Bonding Strength in Magnesium\"><\/iframe><\/div><\/div>\n      <\/section>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">\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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.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-metallic .ols-course-cta-intro-stats {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .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-metallic {\r\n        margin: 26px 0 22px;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-course-cta-card {\r\n        padding: 20px;\r\n        border-radius: 24px;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-course-cta-header-row {\r\n        align-items: stretch;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-course-button-top {\r\n        width: 100%;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-course-cta-stats,\r\n      .ols-course-cta-ionic-metallic .ols-course-cta-features {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-course-animation-wrap {\r\n        padding: 0;\r\n        border-radius: 0;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-animation-frame-shell {\r\n        height: 420px;\r\n        border-radius: 18px;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .ols-animation-play-circle {\r\n        width: 76px;\r\n        height: 76px;\r\n      }\r\n\r\n      .ols-course-cta-ionic-metallic .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-metallic .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-metallic .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\/metallic-bonding-edexcel-a-level-chemistry\/\" aria-label=\"Open the Edexcel A Level Chemistry Topic 2A\/B 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\/05\/T2AB-Course-Card.jpg\"\r\n            alt=\"Edexcel A Level Chemistry Topic 2A\/B Ionic and Metallic Bonding course card\"\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            Complete Topic 2A\/B Ionic & Metallic Bonding Course\r\n          <\/div>\r\n\r\n          <a class=\"ols-course-button ols-course-button-top\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/product\/metallic-bonding-edexcel-a-level-chemistry\/\">\r\n            View Course\r\n          <\/a>\r\n\r\n        <\/div>\r\n\r\n        <h2>\r\n          Master Ionic Bonding and Metallic Bonding 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 2A\/B Ionic and Metallic Bonding 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>11 hours<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Video lessons<\/span>\r\n          <strong>288 mins<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>MCQ practice<\/span>\r\n          <strong>51 marks<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>SAQ practice<\/span>\r\n          <strong>68 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 ions, ionic lattices, polarisation and metallic bonding 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 ions, ionic bonding, ionic radii, polarisation and metallic bonding 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\/metallic-bonding-edexcel-a-level-chemistry\/\">\r\n        View Ionic & Metallic Bonding Topic 2A\/B 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  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-ionic-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-ionic-table th,\r\n.mcq-ionic-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-ionic-table th{\r\n  background:#f2f2f2;\r\n  font-weight:700;\r\n}\r\n\r\n.mcq-ionic-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 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}\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\">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\" 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  <\/section>\r\n\r\n<\/div>\r\n\r\n<script>\r\n(function(){\r\n  const nativeSetTimeout=window.setTimeout.bind(window);\r\n  const nativeClearTimeout=window.clearTimeout.bind(window);\r\n  let nextTimerId=1;\r\n  let paused=false;\r\n  const 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},850);\r\n        },3000);\r\n      },250);\r\n    });\r\n  },700);\r\n}\r\n\r\nconst mcqIntroTitle=\"Multiple Choice Question Bank\";\r\nconst mcqSpecificFeedbackText=\"Na\u207a is small, but Cl\u207b is larger than F\u207b, so the ionic bonding is weaker than in NaF.\";\r\nconst mcqGeneralFeedbackText=\r\n\"Your answer is incorrect.\\n\\n\"+\r\n\"To determine which compound has the strongest ionic bonding, recall the key principle:\\n\\n\"+\r\n\"\u2022 Ionic bond strength increases when ionic radii are small, because 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 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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 2.<\/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-2-bonding-and-structure\/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\/edexcel\/topic-2-bonding-and-structure\/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\/edexcel\/topic-2-bonding-and-structure\/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\/edexcel\/topic-2-bonding-and-structure\/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\/edexcel\/topic-2-bonding-and-structure\/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\/edexcel\/topic-2-bonding-and-structure\/\">Topic 2 Bonding and Structure<\/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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