{"id":7719,"date":"2026-09-12T12:07:59","date_gmt":"2026-09-12T11:07:59","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/sigma-and-pi-bonds-and-hybridisation\/"},"modified":"2026-09-22T13:32:37","modified_gmt":"2026-09-22T12:32:37","slug":"sigma-and-pi-bonds-and-hybridisation","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/sigma-and-pi-bonds-and-hybridisation\/","title":{"rendered":"Sigma and Pi Bonds and Hybridisation"},"content":{"rendered":"<script src=\"https:\/\/cdnjs.cloudflare.com\/ajax\/libs\/three.js\/r128\/three.min.js\"><\/script>\n\n<section class=\"ols-revision-page ols-nature-of-covalent-bonding-9ch0-page\">\n  <style>\n    .ols-revision-page {\n      --navy: #1C244B;\n      --blue: #2563eb;\n      --soft-blue: #eef4ff;\n      --soft-red: #fff7f7;\n    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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>3.4 Covalent 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\/covalent-bonding\/\">Part overview<\/a><\/li>\n      <li><a 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><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/dative-covalent-bonding\/\">Dative Covalent Bonding<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/giant-covalent-structures\/\">Giant Covalent Structures<\/a><\/li>\n<li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/sigma-and-pi-bonds-and-hybridisation\/\">Sigma and Pi Bonds and Hybridisation<\/a><\/li>\n<li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/bond-energy-and-bond-length\/\">Bond Energy and Bond Length<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/covalent-bonding\/polar-molecules\/\">Non-Polar and Polar Molecules<\/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\/shapes-of-molecules\/\">3.5 Shapes of Molecules<\/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\/covalent-bonding\/\">3.4 Covalent Bonding<\/a> \/\n<span>Sigma and Pi Bonds and Hybridisation<\/span>\n<\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Sigma and Pi Bonds and Hybridisation<\/h1>\n        <p class=\"ols-page-intro\">A concise Cambridge International AS Level Chemistry revision guide to 3.4.2: how \u03c3 and \u03c0 bonds form by orbital overlap, how the bonds in nitrogen and hydrogen cyanide are built up, and how sp, sp<sup>2<\/sup> and sp<sup>3<\/sup> hybridisation explains the number of bonds and the shape around each atom.<\/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\n    <img decoding=\"async\"\n      class=\"ols-author-avatar-img\"\n      src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\"\n      alt=\"Dr. Mohammed Al-Fatah\"\n    >\n\n    <div class=\"ols-author-content\">\n\n      <h2 class=\"ols-author-title\">\n        Written by:<br><span>Dr. Mohammed Al-Fatah<\/span>\n      <\/h2>\n\n      <p class=\"ols-author-description\">\n        Chemistry specialist revision notes for A Level Chemistry.\n      <\/p>\n\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\"\/>\n        <\/svg>\n        View LinkedIn Profile\n      <\/a>\n\n    <\/div>\n\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>Sigma and Pi Bonds Are Two Kinds of Overlap<\/h2>\n<\/div>\n<p>A covalent bond forms when two atomic orbitals overlap and the shared pair occupies the region between the nuclei. Cambridge distinguishes two ways this can happen.<\/p>\n<div class=\"ols-table-wrap\">\n<table class=\"ols-table\">\n<thead>\n<tr><th>Bond<\/th><th>How the orbitals overlap<\/th><th>Where the electron density lies<\/th><th>Properties<\/th><\/tr>\n<\/thead>\n<tbody>\n<tr><td><strong>\u03c3 (sigma)<\/strong><\/td><td>End-on (head-on) overlap of s or p orbitals, or of hybrid orbitals<\/td><td>Directly between the two nuclei, along the bond axis<\/td><td>Strong; the first bond between any two atoms; allows free rotation<\/td><\/tr>\n<tr><td><strong>\u03c0 (pi)<\/strong><\/td><td>Sideways overlap of two parallel p orbitals<\/td><td>Above and below the bond axis, in two lobes<\/td><td>Weaker than \u03c3; only forms after a \u03c3 bond; prevents rotation<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>A single bond is one \u03c3 bond. A double bond is one \u03c3 bond plus one \u03c0 bond. A triple bond is one \u03c3 bond plus <strong>two<\/strong> \u03c0 bonds, with the two \u03c0 bonds at right angles to each other around the axis.<\/p>\n<div class=\"ols-key-box\">\n<p><strong>Exam sentence:<\/strong> A \u03c3 bond forms by end-on overlap of orbitals along the internuclear axis; a \u03c0 bond forms by sideways overlap of p orbitals, giving electron density above and below the axis.<\/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: Count the Sigma and Pi Bonds<\/h2>\n<p>Draw the molecule out, then count the two kinds of bond.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-450\" class=\"h5p-iframe\" data-content-id=\"450\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Sigma and Pi MCQ: Counting the Bonds in Buta-1,3-diene\"><\/iframe><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">2<\/div>\n<h2>Hybridisation: sp, sp<sup>2<\/sup> and sp<sup>3<\/sup><\/h2>\n<\/div>\n<p>Carbon is 1s<sup>2<\/sup> 2s<sup>2<\/sup> 2p<sup>2<\/sup>, which suggests only two bonds, yet it always forms four. The explanation is <strong>hybridisation<\/strong>: the 2s orbital mixes with some or all of the 2p orbitals to give a set of identical hybrid orbitals, and any p orbitals left unmixed are used for \u03c0 bonds.<\/p>\n<div class=\"ols-table-wrap\">\n<table class=\"ols-table\">\n<thead>\n<tr><th>Hybridisation<\/th><th>Orbitals mixed<\/th><th>Hybrid orbitals<\/th><th>p orbitals left for \u03c0 bonds<\/th><th>Shape and angle<\/th><th>Example<\/th><\/tr>\n<\/thead>\n<tbody>\n<tr><td><strong>sp<sup>3<\/sup><\/strong><\/td><td>2s + three 2p<\/td><td>Four<\/td><td>None<\/td><td>Tetrahedral, 109.5\u00b0<\/td><td>Carbon in methane and every alkane carbon<\/td><\/tr>\n<tr><td><strong>sp<sup>2<\/sup><\/strong><\/td><td>2s + two 2p<\/td><td>Three<\/td><td>One<\/td><td>Trigonal planar, 120\u00b0<\/td><td>Each carbon in ethene; carbonyl carbon<\/td><\/tr>\n<tr><td><strong>sp<\/strong><\/td><td>2s + one 2p<\/td><td>Two<\/td><td>Two<\/td><td>Linear, 180\u00b0<\/td><td>Each carbon in ethyne; the carbon in HCN; each nitrogen in N<sub>2<\/sub><\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>The number of hybrid orbitals always equals the number of atomic orbitals mixed, and the hybrid orbitals make the \u03c3 bonds and hold lone pairs. The Topic 13 pages on <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-13-an-introduction-to-as-level-organic-chemistry\/shapes-of-organic-molecules\/alkanes-and-sp3-carbon\/\">sp<sup>3<\/sup> carbon in alkanes<\/a> and <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-13-an-introduction-to-as-level-organic-chemistry\/shapes-of-organic-molecules\/alkynes-and-nitriles-sp-carbon\/\">sp carbon in alkynes and nitriles<\/a> apply the same idea to organic molecules.<\/p>\n\n<section class=\"ols-hyb-001\" id=\"olsHyb001\">\n<style>\n@import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600&display=swap');\n\n.ols-hyb-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  color:#1C244B;\n  background:#ffffff;\n  border:1px solid rgba(28,36,75,0.14);\n  border-radius:28px;\n  box-shadow:0 18px 45px rgba(28,36,75,0.10);\n  padding:44px;\n  margin:26px auto;\n  max-width:980px;\n  box-sizing:border-box;\n  -webkit-font-smoothing:antialiased;\n}\n.ols-hyb-001 *{box-sizing:border-box;}\n\n.ols-hyb-001 .hyb-head{margin:0 0 22px;}\n.ols-hyb-001 h2.hyb-title{\n  font-size:26px; 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color:#aab0c0;\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;}\n.ols-hyb-001-cc a{color:#aab0c0; text-decoration:none;}\n.ols-hyb-001-cc a:hover{text-decoration:underline;}\n\n@media (max-width:760px){\n  .ols-hyb-001{padding:26px; border-radius:22px;}\n  .ols-hyb-001 h2.hyb-title{font-size:20.5px;}\n  .ols-hyb-001 p.hyb-sub{font-size:13.5px;}\n  .ols-hyb-001 .hyb-stage{height:420px;}\n  .ols-hyb-001 .hyb-rowlab{min-width:100%;}\n  .ols-hyb-001 .hyb-seg button{padding:9px 15px; font-size:13.5px;}\n  .ols-hyb-001 .hyb-lab{font-size:10.5px; padding:4px 8px;}\n  .ols-hyb-001 .hyb-lab.l-ang{font-size:12px;}\n  .ols-hyb-001 .hyb-info{padding:18px;}\n}\n@media (prefers-reduced-motion:reduce){\n  .ols-hyb-001 .hyb-seg button,.ols-hyb-001 .hyb-pill{transition:none;}\n}\n<\/style>\n\n<div class=\"hyb-head\">\n  <h2 class=\"hyb-title\">Hybridisation of Carbon: sp&sup3;, sp&sup2; and sp Orbitals<\/h2>\n  <p class=\"hyb-sub\">Drag to rotate, scroll or pinch to zoom. Switch between the three states to see how mixing the 2s and 2p orbitals changes the shape around the carbon nucleus, and which 2p orbitals are left unhybridised.<\/p>\n<\/div>\n\n<div class=\"hyb-stage\" id=\"hybStage\">\n  <canvas class=\"hyb-canvas\" id=\"hybCanvas\"><\/canvas>\n  <div class=\"hyb-overlay\" id=\"hybOverlay\"><\/div>\n  <div class=\"hyb-hint\" id=\"hybHint\">Drag to rotate<\/div>\n<\/div>\n\n<div class=\"hyb-controls\">\n  <div class=\"hyb-row\">\n    <span class=\"hyb-rowlab\">Hybridisation<\/span>\n    <div class=\"hyb-seg\" role=\"group\" aria-label=\"Hybridisation state\">\n      <button type=\"button\" data-state=\"sp3\" aria-pressed=\"true\">sp&sup3;<\/button>\n      <button type=\"button\" data-state=\"sp2\" aria-pressed=\"false\">sp&sup2;<\/button>\n      <button type=\"button\" data-state=\"sp\" aria-pressed=\"false\">sp<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"hyb-row\">\n    <span class=\"hyb-rowlab\">View<\/span>\n    <div class=\"hyb-seg\" role=\"group\" aria-label=\"Camera view\">\n      <button type=\"button\" data-view=\"front\" aria-pressed=\"false\">Front<\/button>\n      <button type=\"button\" data-view=\"side\" aria-pressed=\"false\">Side<\/button>\n      <button type=\"button\" data-view=\"top\" aria-pressed=\"false\">Top<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"hyb-row\">\n    <span class=\"hyb-rowlab\">Show<\/span>\n    <button type=\"button\" class=\"hyb-pill\" id=\"hybTogHyb\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Hybrid orbitals<\/button>\n    <button type=\"button\" class=\"hyb-pill p-orange\" id=\"hybTogP\" aria-pressed=\"true\"><i class=\"dot\"><\/i>p orbitals<\/button>\n    <button type=\"button\" class=\"hyb-pill\" id=\"hybTogLab\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Labels<\/button>\n  <\/div>\n\n  <div class=\"hyb-row\">\n    <span class=\"hyb-rowlab\">Motion<\/span>\n    <button type=\"button\" class=\"hyb-pill\" id=\"hybSpin\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Rotation<\/button>\n    <button type=\"button\" class=\"hyb-pill\" id=\"hybReset\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"hyb-info\">\n  <h3 id=\"hybInfoTitle\">sp&sup3; hybridisation<\/h3>\n  <p id=\"hybInfoText\"><\/p>\n  <div class=\"hyb-facts\">\n    <div class=\"hyb-fact\"><span>Hybrid orbitals<\/span><strong id=\"hybFactN\">4<\/strong><\/div>\n    <div class=\"hyb-fact\"><span>Bond angle<\/span><strong id=\"hybFactA\">109.5&deg;<\/strong><\/div>\n    <div class=\"hyb-fact\"><span>Shape<\/span><strong id=\"hybFactG\">Tetrahedral<\/strong><\/div>\n    <div class=\"hyb-fact\"><span>Unhybridised 2p<\/span><strong id=\"hybFactP\">None<\/strong><\/div>\n    <div class=\"hyb-fact\"><span>Example<\/span><strong id=\"hybFactE\">Methane, CH<sub>4<\/sub><\/strong><\/div>\n  <\/div>\n  <div class=\"hyb-key\">\n    <span><i class=\"k-b\"><\/i>Hybrid orbital<\/span>\n    <span><i class=\"k-o\"><\/i>Unhybridised 2p<\/span>\n    <span><i class=\"k-p\"><\/i>Second unhybridised 2p<\/span>\n    <span><i class=\"k-r\"><\/i>Carbon nucleus<\/span>\n  <\/div>\n<\/div>\n\n<script src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/JS\/hybridisation-carbon.js\"><\/script>\n<\/section>\n<p class=\"ols-hyb-001-cc\">&copy; Dr. Mohammed Al-Fatah &#8211; <a href=\"https:\/\/www.onlinelearningsystem.net\" target=\"_blank\" rel=\"noopener\">onlinelearningsystem.net<\/a><\/p>\n\n<div class=\"ols-key-box\">\n<p><strong>Key idea:<\/strong> Count the atoms and lone pairs around the atom: four means sp<sup>3<\/sup>, three means sp<sup>2<\/sup>, two means sp. The leftover p orbitals tell you how many \u03c0 bonds the atom makes.<\/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: Two Kinds of Carbon in One Molecule<\/h2>\n<p>Drag the words and numbers into place to describe the bonding in propyne.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-449\" class=\"h5p-iframe\" data-content-id=\"449\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Hybridisation Drag: Two Kinds of Carbon in Propyne\"><\/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 the Two Forms of But-2-ene<\/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-452\" class=\"h5p-iframe\" data-content-id=\"452\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Sigma and Pi Explain: Why But-2-ene Exists as Two Compounds\"><\/iframe><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card purple\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">3<\/div>\n<h2>The Bonding in Nitrogen, N<sub>2<\/sub><\/h2>\n<\/div>\n<p>Each nitrogen atom is 1s<sup>2<\/sup> 2s<sup>2<\/sup> 2p<sup>3<\/sup>. In N<sub>2<\/sub> each atom is <strong>sp hybridised<\/strong>: the 2s orbital mixes with one 2p orbital to give two sp hybrids pointing in opposite directions, leaving two unhybridised p orbitals at right angles.<\/p>\n<ul>\n<li>One sp orbital on each nitrogen overlaps end-on with the sp orbital of the other nitrogen: this is the <strong>N-N \u03c3 bond<\/strong>.<\/li>\n<li>The other sp orbital on each nitrogen points away from the bond and holds the <strong>lone pair<\/strong>.<\/li>\n<li>The two unhybridised p orbitals on each nitrogen overlap sideways with their partners on the other atom to give <strong>two \u03c0 bonds<\/strong>, one above and below the axis and one in front and behind.<\/li>\n<\/ul>\n<p>The result is a triple bond, N\u2261N, made of one \u03c3 and two \u03c0 bonds, with a lone pair on each nitrogen. The three bonds together are very strong, which is why nitrogen gas is so unreactive.<\/p>\n\n<section class=\"ols-n2-001\" id=\"olsN2001\">\n<style>\n@import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600&display=swap');\n\n.ols-n2-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  color:#1C244B; background:#ffffff;\n  border:1px solid rgba(28,36,75,0.14);\n  border-radius:28px;\n  box-shadow:0 18px 45px rgba(28,36,75,0.10);\n  padding:44px; margin:26px auto; max-width:980px;\n  box-sizing:border-box; -webkit-font-smoothing:antialiased;\n}\n.ols-n2-001 *{box-sizing:border-box;}\n\n.ols-n2-001 .n2-head{margin:0 0 22px;}\n.ols-n2-001 h2.n2-title{\n  font-size:26px; line-height:1.25; font-weight:600; letter-spacing:-0.012em;\n  margin:0 0 9px; color:#1C244B;\n}\n.ols-n2-001 p.n2-sub{\n  font-size:14.5px; line-height:1.62; font-weight:300; color:#4a5270;\n  margin:0; max-width:66ch;\n}\n\n.ols-n2-001 .n2-stage{\n  position:relative; 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border-radius:22px;}\n  .ols-n2-001 h2.n2-title{font-size:20.5px;}\n  .ols-n2-001 p.n2-sub{font-size:13.5px;}\n  .ols-n2-001 .n2-stage{height:420px;}\n  .ols-n2-001 .n2-rowlab{min-width:100%;}\n  .ols-n2-001 .n2-seg button{padding:9px 14px; font-size:13.5px;}\n  .ols-n2-001 .n2-lab{font-size:10.5px; padding:4px 8px;}\n  .ols-n2-001 .n2-lab.l-dim{font-size:11.5px;}\n  .ols-n2-001 .n2-caption{font-size:10.5px; padding:5px 9px; max-width:64%;}\n  .ols-n2-001 .n2-info{padding:18px;}\n}\n@media (prefers-reduced-motion:reduce){\n  .ols-n2-001 .n2-seg button,.ols-n2-001 .n2-pill{transition:none;}\n}\n\n.ols-cc-n2-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  margin:10px auto 0; text-align:center; font-size:11px; font-style:italic; color:#aab0c0;\n}\n.ols-cc-n2-001 a{color:#aab0c0; text-decoration:none;}\n.ols-cc-n2-001 a:hover{text-decoration:underline;}\n<\/style>\n\n<div class=\"n2-head\">\n  <h2 class=\"n2-title\">Bonding in Nitrogen, N<sub>2<\/sub>: sp Hybrids, Sigma and Pi Bonds<\/h2>\n  <p class=\"n2-sub\">Drag to rotate, scroll or pinch to zoom. Build the molecule one layer at a time, from the orbitals each nitrogen brings through to the finished triple bond. The side view looks straight down the molecule and shows both pi bonds at right angles.<\/p>\n<\/div>\n\n<div class=\"n2-stage\" id=\"n2Stage\">\n  <canvas class=\"n2-canvas\" id=\"n2Canvas\"><\/canvas>\n  <div class=\"n2-overlay\" id=\"n2Overlay\"><\/div>\n  <div class=\"n2-caption\" id=\"n2Caption\"><\/div>\n  <div class=\"n2-hint\" id=\"n2Hint\">Drag to rotate<\/div>\n<\/div>\n\n<div class=\"n2-controls\">\n  <div class=\"n2-row\">\n    <span class=\"n2-rowlab\">Bonding layer<\/span>\n    <div class=\"n2-seg\" role=\"group\" aria-label=\"Bonding layer\">\n      <button type=\"button\" data-stage=\"hyb\" aria-pressed=\"true\">Atomic orbitals<\/button>\n      <button type=\"button\" data-stage=\"sig\" aria-pressed=\"false\">Sigma bond<\/button>\n      <button type=\"button\" data-stage=\"pi\" aria-pressed=\"false\">Pi bonds<\/button>\n      <button type=\"button\" data-stage=\"all\" aria-pressed=\"false\">Molecular orbitals<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"n2-row\">\n    <span class=\"n2-rowlab\">View<\/span>\n    <div class=\"n2-seg\" role=\"group\" aria-label=\"Camera view\">\n      <button type=\"button\" data-view=\"front\" aria-pressed=\"false\">Front<\/button>\n      <button type=\"button\" data-view=\"side\" aria-pressed=\"false\">Side<\/button>\n      <button type=\"button\" data-view=\"top\" aria-pressed=\"false\">Top<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"n2-row\">\n    <span class=\"n2-rowlab\">Show<\/span>\n    <button type=\"button\" class=\"n2-pill p-orange\" id=\"n2TogP\" aria-pressed=\"true\"><i class=\"dot\"><\/i>p orbitals<\/button>\n    <button type=\"button\" class=\"n2-pill p-rose\" id=\"n2TogLP\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Lone pairs<\/button>\n    <button type=\"button\" class=\"n2-pill\" id=\"n2TogDim\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Bond length<\/button>\n    <button type=\"button\" class=\"n2-pill\" id=\"n2TogLab\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Labels<\/button>\n  <\/div>\n\n  <div class=\"n2-row\">\n    <span class=\"n2-rowlab\">Motion<\/span>\n    <button type=\"button\" class=\"n2-pill\" id=\"n2Spin\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Rotation<\/button>\n    <button type=\"button\" class=\"n2-pill\" id=\"n2Reset\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"n2-info\">\n  <h3 id=\"n2InfoTitle\"><\/h3>\n  <p id=\"n2InfoText\"><\/p>\n  <div class=\"n2-facts\" id=\"n2Facts\"><\/div>\n  <div class=\"n2-key\">\n    <span><i class=\"k-b\"><\/i>sp hybrid and sigma bond<\/span>\n    <span><i class=\"k-o\"><\/i>Pi bond from 2p<sub>y<\/sub><\/span>\n    <span><i class=\"k-p\"><\/i>Pi bond from 2p<sub>z<\/sub><\/span>\n    <span><i class=\"k-l\"><\/i>Lone pair<\/span>\n    <span><i class=\"k-n\"><\/i>Nitrogen nucleus<\/span>\n  <\/div>\n<\/div>\n<\/section>\n\n<p class=\"ols-cc-n2-001\">&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\/n2-bonding.js\"><\/script>\n\n<div class=\"ols-key-box\">\n<p><strong>Exam sentence:<\/strong> In N<sub>2<\/sub> each nitrogen is sp hybridised: the sp orbitals form one \u03c3 bond and hold the lone pairs, and the two remaining p orbitals on each atom overlap sideways to form two \u03c0 bonds.<\/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: Name the Hybridisation<\/h2>\n<p>Count the bonded atoms and the lone pairs together for each atom.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-451\" class=\"h5p-iframe\" data-content-id=\"451\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Hybridisation Quick Fire: Counting Lone Pairs as Well as Bonds\"><\/iframe><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">4<\/div>\n<h2>The Bonding in Hydrogen Cyanide, HCN<\/h2>\n<\/div>\n<p>HCN is linear, H-C\u2261N, and both the carbon and the nitrogen are <strong>sp hybridised<\/strong>. The three atoms are held by two \u03c3 bonds and two \u03c0 bonds.<\/p>\n<div class=\"ols-table-wrap\">\n<table class=\"ols-table\">\n<thead>\n<tr><th>Bond<\/th><th>Orbitals that overlap<\/th><th>Type<\/th><\/tr>\n<\/thead>\n<tbody>\n<tr><td><strong>H-C<\/strong><\/td><td>1s orbital of hydrogen with an sp orbital of carbon (end-on)<\/td><td>\u03c3<\/td><\/tr>\n<tr><td><strong>C-N (first bond)<\/strong><\/td><td>sp orbital of carbon with an sp orbital of nitrogen (end-on)<\/td><td>\u03c3<\/td><\/tr>\n<tr><td><strong>C-N (second and third bonds)<\/strong><\/td><td>The two unhybridised p orbitals on carbon with the two on nitrogen (sideways)<\/td><td>Two \u03c0<\/td><\/tr>\n<tr><td><strong>Nitrogen lone pair<\/strong><\/td><td>The second sp orbital of nitrogen, pointing away from carbon<\/td><td>Lone pair<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>Carbon therefore makes four bonds (one \u03c3 to H, one \u03c3 and two \u03c0 to N) and nitrogen makes three bonds plus a lone pair. Because both central atoms are sp hybridised the H-C-N bond angle is 180\u00b0.<\/p>\n\n<section class=\"ols-hcn-001\" id=\"olsHcn001\">\n<style>\n@import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600&display=swap');\n\n.ols-hcn-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  color:#1C244B; background:#ffffff;\n  border:1px solid rgba(28,36,75,0.14);\n  border-radius:28px;\n  box-shadow:0 18px 45px rgba(28,36,75,0.10);\n  padding:44px; margin:26px auto; max-width:980px;\n  box-sizing:border-box; -webkit-font-smoothing:antialiased;\n}\n.ols-hcn-001 *{box-sizing:border-box;}\n\n.ols-hcn-001 .hcn-head{margin:0 0 22px;}\n.ols-hcn-001 h2.hcn-title{\n  font-size:26px; line-height:1.25; font-weight:600; letter-spacing:-0.012em;\n  margin:0 0 9px; color:#1C244B;\n}\n.ols-hcn-001 p.hcn-sub{\n  font-size:14.5px; line-height:1.62; font-weight:300; color:#4a5270;\n  margin:0; max-width:66ch;\n}\n\n.ols-hcn-001 .hcn-stage{\n  position:relative; 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border-radius:22px;}\n  .ols-hcn-001 h2.hcn-title{font-size:20.5px;}\n  .ols-hcn-001 p.hcn-sub{font-size:13.5px;}\n  .ols-hcn-001 .hcn-stage{height:420px;}\n  .ols-hcn-001 .hcn-rowlab{min-width:100%;}\n  .ols-hcn-001 .hcn-seg button{padding:9px 14px; font-size:13.5px;}\n  .ols-hcn-001 .hcn-lab{font-size:10.5px; padding:4px 8px;}\n  .ols-hcn-001 .hcn-lab.l-ang{font-size:12px;}\n  .ols-hcn-001 .hcn-caption{font-size:10.5px; padding:5px 9px; max-width:64%;}\n  .ols-hcn-001 .hcn-info{padding:18px;}\n}\n@media (prefers-reduced-motion:reduce){\n  .ols-hcn-001 .hcn-seg button,.ols-hcn-001 .hcn-pill{transition:none;}\n}\n\n.ols-cc-hcn-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  margin:10px auto 0; text-align:center; font-size:11px; font-style:italic; color:#aab0c0;\n}\n.ols-cc-hcn-001 a{color:#aab0c0; text-decoration:none;}\n.ols-cc-hcn-001 a:hover{text-decoration:underline;}\n<\/style>\n\n<div class=\"hcn-head\">\n  <h2 class=\"hcn-title\">Bonding in Hydrogen Cyanide, HCN: sp Hybrids, Sigma and Pi Bonds<\/h2>\n  <p class=\"hcn-sub\">Drag to rotate, scroll or pinch to zoom. Build the molecule one layer at a time, from the sp hybrid orbitals on carbon and nitrogen through to the finished triple bond and the lone pair. The side view looks straight down the molecule and shows both pi bonds at right angles.<\/p>\n<\/div>\n\n<div class=\"hcn-stage\" id=\"hcnStage\">\n  <canvas class=\"hcn-canvas\" id=\"hcnCanvas\"><\/canvas>\n  <div class=\"hcn-overlay\" id=\"hcnOverlay\"><\/div>\n  <div class=\"hcn-caption\" id=\"hcnCaption\"><\/div>\n  <div class=\"hcn-hint\" id=\"hcnHint\">Drag to rotate<\/div>\n<\/div>\n\n<div class=\"hcn-controls\">\n  <div class=\"hcn-row\">\n    <span class=\"hcn-rowlab\">Bonding layer<\/span>\n    <div class=\"hcn-seg\" role=\"group\" aria-label=\"Bonding layer\">\n      <button type=\"button\" data-stage=\"hyb\" aria-pressed=\"true\">Atomic orbitals<\/button>\n      <button type=\"button\" data-stage=\"sig\" aria-pressed=\"false\">Sigma bonds<\/button>\n      <button type=\"button\" data-stage=\"pi\" aria-pressed=\"false\">Pi bonds<\/button>\n      <button type=\"button\" data-stage=\"all\" aria-pressed=\"false\">Molecular orbitals<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"hcn-row\">\n    <span class=\"hcn-rowlab\">View<\/span>\n    <div class=\"hcn-seg\" role=\"group\" aria-label=\"Camera view\">\n      <button type=\"button\" data-view=\"front\" aria-pressed=\"false\">Front<\/button>\n      <button type=\"button\" data-view=\"side\" aria-pressed=\"false\">Side<\/button>\n      <button type=\"button\" data-view=\"top\" aria-pressed=\"false\">Top<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"hcn-row\">\n    <span class=\"hcn-rowlab\">Show<\/span>\n    <button type=\"button\" class=\"hcn-pill p-orange\" id=\"hcnTogP\" aria-pressed=\"true\"><i class=\"dot\"><\/i>p orbitals<\/button>\n    <button type=\"button\" class=\"hcn-pill p-rose\" id=\"hcnTogLP\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Lone pair<\/button>\n    <button type=\"button\" class=\"hcn-pill\" id=\"hcnTogAng\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Bond angle<\/button>\n    <button type=\"button\" class=\"hcn-pill\" id=\"hcnTogLab\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Labels<\/button>\n  <\/div>\n\n  <div class=\"hcn-row\">\n    <span class=\"hcn-rowlab\">Motion<\/span>\n    <button type=\"button\" class=\"hcn-pill\" id=\"hcnSpin\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Rotation<\/button>\n    <button type=\"button\" class=\"hcn-pill\" id=\"hcnReset\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"hcn-info\">\n  <h3 id=\"hcnInfoTitle\">Hybrid orbitals<\/h3>\n  <p id=\"hcnInfoText\"><\/p>\n  <div class=\"hcn-facts\" id=\"hcnFacts\"><\/div>\n  <div class=\"hcn-key\">\n    <span><i class=\"k-b\"><\/i>sp hybrid and sigma bond<\/span>\n    <span><i class=\"k-g\"><\/i>Hydrogen 1s orbital<\/span>\n    <span><i class=\"k-o\"><\/i>Pi bond from 2p<sub>y<\/sub><\/span>\n    <span><i class=\"k-p\"><\/i>Pi bond from 2p<sub>z<\/sub><\/span>\n    <span><i class=\"k-l\"><\/i>Lone pair on nitrogen<\/span>\n    <span><i class=\"k-c\"><\/i>Carbon nucleus<\/span>\n    <span><i class=\"k-n\"><\/i>Nitrogen nucleus<\/span>\n    <span><i class=\"k-h\"><\/i>Hydrogen nucleus<\/span>\n  <\/div>\n<\/div>\n<\/section>\n\n<p class=\"ols-cc-hcn-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\/hcn-bonding.js\"><\/script>\n\n<div class=\"ols-key-box\">\n<p><strong>Exam sentence:<\/strong> In HCN the H-C and C-N \u03c3 bonds form by end-on overlap with sp orbitals of carbon, and the two C-N \u03c0 bonds form by sideways overlap of the unhybridised p orbitals on carbon and nitrogen.<\/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: Spot the Accurate Description<\/h2>\n<p>In each round, choose the one statement that describes the bonding correctly.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-842\" class=\"h5p-iframe\" data-content-id=\"842\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Sigma and Pi Summary: Spot the Accurate Description\"><\/iframe><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card soft\">\n<div class=\"ols-note-title\">\n<div class=\"ols-note-icon\">5<\/div>\n<h2>Common Exam Mistakes<\/h2>\n<\/div>\n<ul>\n<li>Saying a triple bond is three identical bonds. It is one \u03c3 bond and two \u03c0 bonds, and the \u03c0 bonds are weaker.<\/li>\n<li>Describing a \u03c0 bond as forming &#8220;between the atoms&#8221;. The \u03c0 electron density lies above and below the bond axis, not along it.<\/li>\n<li>Forgetting that hybrid orbitals hold lone pairs as well as forming \u03c3 bonds. The lone pair on nitrogen in N<sub>2<\/sub> and HCN is in an sp orbital.<\/li>\n<li>Choosing the wrong hybridisation for an atom with a lone pair. Count lone pairs as well as bonded atoms: the oxygen in water has four electron pairs and is sp<sup>3<\/sup>.<\/li>\n<li>Claiming free rotation about a double bond. The \u03c0 bond locks the geometry, which is why alkenes show geometric isomerism.<\/li>\n<\/ul>\n<div class=\"ols-key-box\">\n<p><strong>Exam sentence:<\/strong> \u03c3 first, \u03c0 second: every bond starts with one \u03c3 bond, and each extra bond order adds one \u03c0 bond from a leftover p orbital.<\/p>\n<\/div>\n<\/article>\n\n<section class=\"ols-course-cta-covalent\" id=\"olsCourseCtaCovalent001\">\r\n  <style>\r\n    .ols-course-cta-covalent,\r\n    .ols-course-cta-covalent * {\r\n      box-sizing: border-box;\r\n    }\r\n\r\n    .ols-course-cta-covalent {\r\n      --navy: #1C244B;\r\n      --blue: #2563eb;\r\n      --body-text: #1f2937;\r\n      --grey-text: #667085;\r\n      --border: rgba(28, 36, 75, 0.14);\r\n      --shadow: 0 18px 45px rgba(28, 36, 75, 0.12);\r\n      --inner-shadow: 0 10px 26px rgba(28, 36, 75, 0.08);\r\n\r\n      width: 100%;\r\n      margin: 30px 0 24px;\r\n      font-family: Poppins, Arial, sans-serif;\r\n    }\r\n\r\n    .ols-course-cta-covalent 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class=\"ols-course-cta-top\">\r\n\r\n      <a class=\"ols-course-cta-image-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/product\/covalent-bonding-and-shapes-of-molecules-topic-3-cambridge-international\/\" aria-label=\"Open the Cambridge International AS and A Level Chemistry Topic 3 Covalent Bonding and Shapes of Molecules 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-covalent-bonding-shapes-interactive-course-banner.jpg\"\r\n            alt=\"Cambridge International AS and A Level Chemistry Topic 3 Covalent Bonding and Shapes of Molecules 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\/covalent-bonding-and-shapes-of-molecules-topic-3-cambridge-international\/\">\r\n            View Course\r\n          <\/a>\r\n\r\n        <\/div>\r\n\r\n        <h2>\r\n          Master Covalent Bonding and Shapes of Molecules 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 Covalent Bonding and Shapes of Molecules 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\/covalent-bonding-and-shapes-of-molecules-topic-3-cambridge-international\/\">\r\n        View Covalent Bonding and Shapes of Molecules 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 auto;\r\n}\r\n\r\n.mcq-radio::after{\r\n  content:\"\";\r\n  position:absolute;\r\n  inset:5px;\r\n  border-radius:50%;\r\n  background:#6b7280;\r\n  opacity:0;\r\n  transform:scale(0.4);\r\n  transition:opacity 0.25s ease,transform 0.25s ease;\r\n}\r\n\r\n.mcq-option-row.selected .mcq-radio::after{\r\n  opacity:1;\r\n  transform:scale(1);\r\n}\r\n\r\n.mcq-radio-ripple{\r\n  position:absolute;\r\n  left:14px;\r\n  top:50%;\r\n  width:28px;\r\n  height:28px;\r\n  border-radius:50%;\r\n  border:2px solid rgba(28,36,75,0.28);\r\n  transform:translate(-50%,-50%) scale(1);\r\n  opacity:0;\r\n  pointer-events:none;\r\n}\r\n\r\n.mcq-option-row.clicking .mcq-radio-ripple{\r\n  animation:mcqRipple 0.75s ease forwards;\r\n}\r\n\r\n@keyframes mcqRipple{\r\n  0%{opacity:0.65;transform:translate(-50%,-50%) scale(1);}\r\n  100%{opacity:0;transform:translate(-50%,-50%) scale(2.5);}\r\n}\r\n\r\n.mcq-option-label{\r\n  font-size:23px;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-specific-feedback{\r\n  display:inline-flex;\r\n  align-items:center;\r\n  margin-left:18px;\r\n  min-height:38px;\r\n  opacity:0;\r\n  transform:translateX(-8px);\r\n}\r\n\r\n.mcq-specific-feedback.show{\r\n  opacity:1;\r\n  transform:translateX(0);\r\n  transition:opacity 0.35s ease,transform 0.35s ease;\r\n}\r\n\r\n.mcq-cross-icon{\r\n  width:26px;\r\n  height:26px;\r\n  border-radius:50%;\r\n  border:2px solid #d83255;\r\n  color:#d83255;\r\n  display:inline-flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  font-size:18px;\r\n  font-weight:700;\r\n  margin-right:12px;\r\n  opacity:0;\r\n  transform:scale(0.4);\r\n}\r\n\r\n.mcq-cross-icon.show{\r\n  animation:mcqCrossPop 0.35s ease forwards;\r\n}\r\n\r\n@keyframes mcqCrossPop{\r\n  70%{opacity:1;transform:scale(1.18);}\r\n  100%{opacity:1;transform:scale(1);}\r\n}\r\n\r\n.mcq-specific-feedback-text{\r\n  display:inline-block;\r\n  background:#fff4b8;\r\n  color:#111827;\r\n  padding:8px 16px;\r\n  font-size:22px;\r\n  line-height:1.35;\r\n  min-width:850px;\r\n  min-height:44px;\r\n}\r\n\r\n.mcq-submit-button{\r\n  position:absolute;\r\n  right:34px;\r\n  bottom:30px;\r\n  border:0;\r\n  border-radius:999px;\r\n  background:#1C244B;\r\n  color:#ffffff;\r\n  padding:14px 28px;\r\n  font-size:18px;\r\n  font-weight:600;\r\n  box-shadow:0 14px 32px rgba(28,36,75,0.25);\r\n  cursor:default;\r\n  transition:transform 0.2s ease,box-shadow 0.2s ease,background 0.2s ease;\r\n}\r\n\r\n.mcq-submit-button.clicked{\r\n  transform:translateY(2px) scale(0.97);\r\n  background:#26315f;\r\n  box-shadow:0 7px 18px rgba(28,36,75,0.22);\r\n}\r\n\r\n.mcq-general-feedback{\r\n  height:520px;\r\n  background:#fff3c9;\r\n  color:#8a6a00;\r\n  padding:26px 30px 28px;\r\n  font-size:23px;\r\n  line-height:1.34;\r\n  opacity:0;\r\n  transform:translateY(20px);\r\n  transition:opacity 0.7s ease,transform 0.7s ease;\r\n  overflow:hidden;\r\n}\r\n\r\n.mcq-general-feedback.show{\r\n  opacity:1;\r\n  transform:translateY(0);\r\n}\r\n\r\n#mcqGeneralText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.mcq-specific-cursor{background:#111827;}\r\n.mcq-general-cursor{background:#8a6a00;}\r\n\r\n.ols-saq-screen{\r\n  width:1360px;\r\n  height:965px;\r\n  border-radius:22px;\r\n  overflow:hidden;\r\n  background:#eaf0ff;\r\n  box-shadow:0 26px 70px rgba(28,36,75,0.22);\r\n  opacity:0;\r\n  transform:translateY(24px) scale(0.96);\r\n}\r\n\r\n.ols-saq-screen.show{\r\n  animation:olsSaqScreenEnter 1s ease forwards;\r\n}\r\n\r\n@keyframes olsSaqScreenEnter{\r\n  from{opacity:0;transform:translateY(24px) scale(0.96);}\r\n  to{opacity:1;transform:translateY(0) scale(1);}\r\n}\r\n\r\n.saq-question-area{\r\n  height:335px;\r\n  background:#eaf0ff;\r\n  padding:30px 40px 32px;\r\n}\r\n\r\n.saq-question-text{\r\n  font-size:25px;\r\n  line-height:1.42;\r\n  color:#111827;\r\n  margin-bottom:22px;\r\n}\r\n\r\n.saq-student-box{\r\n  height:195px;\r\n  background:#f3f4f6;\r\n  border:2px solid #cfd6e3;\r\n  border-radius:8px;\r\n  padding:23px 26px;\r\n  font-size:24px;\r\n  line-height:1.55;\r\n  color:#4b5563;\r\n  position:relative;\r\n  overflow:hidden;\r\n}\r\n\r\n.saq-teacher-feedback{\r\n  height:630px;\r\n  background:#dff3e6;\r\n  color:#075f3b;\r\n  padding:28px 40px 30px;\r\n  font-size:23px;\r\n  line-height:1.47;\r\n  opacity:0;\r\n  transform:translateY(20px);\r\n  transition:opacity 0.7s ease,transform 0.7s ease;\r\n  overflow:hidden;\r\n}\r\n\r\n.saq-teacher-feedback.show{\r\n  opacity:1;\r\n  transform:translateY(0);\r\n}\r\n\r\n#saqTeacherText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.saq-teacher-cursor{\r\n  background:#075f3b;\r\n}\r\n\r\n@media(max-width:900px){\r\n  .ols-video-title,\r\n  .ols-mcq-intro-title,\r\n  .ols-saq-intro-title{\r\n    font-size:clamp(42px,11vw,78px);\r\n    line-height:1.12;\r\n  }\r\n\r\n  .ols-title-cursor{\r\n    width:4px;\r\n    margin-left:6px;\r\n  }\r\n\r\n  .ols-video-card{\r\n    border-radius:20px;\r\n  }\r\n}\r\n<\/style>\r\n<\/head>\r\n\r\n<body>\r\n<div class=\"ols-combined-stage\">\r\n\r\n  <section id=\"sceneVideo\" class=\"ols-scene active\">\r\n    <div class=\"ols-video-stage\">\r\n      <div id=\"videoTitleScreen\" class=\"ols-video-title-screen\">\r\n        <div class=\"ols-video-title-wrap\">\r\n          <h1 class=\"ols-video-title\">\r\n            <span id=\"videoTitleText\"><\/span><span id=\"videoTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <section id=\"videoScene\" class=\"ols-video-scene\">\r\n        <div class=\"ols-video-scale-wrap\">\r\n          <div class=\"ols-video-card\">\r\n            <video\r\n              id=\"lessonVideo\"\r\n              src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Virtual-Lesson.mp4\"\r\n              muted\r\n              playsinline\r\n              preload=\"auto\">\r\n            <\/video>\r\n          <\/div>\r\n        <\/div>\r\n      <\/section>\r\n    <\/div>\r\n  <\/section>\r\n\r\n  <section id=\"sceneMcq\" class=\"ols-scene\">\r\n    <div class=\"ols-mcq-stage\">\r\n      <div id=\"mcqIntroScreen\" class=\"ols-mcq-intro-screen\">\r\n        <div class=\"ols-mcq-intro-title-wrap\">\r\n          <h1 class=\"ols-mcq-intro-title\">\r\n            <span id=\"mcqIntroTitleText\"><\/span><span id=\"mcqIntroTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <div class=\"ols-mcq-scale-wrap\">\r\n        <main id=\"mcqScreen\" class=\"ols-mcq-screen\">\r\n          <section class=\"mcq-question-area\">\r\n            <p class=\"mcq-question-lead\">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 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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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because it has more atoms packed together and melts at a higher temperature than sodium.\";\r\nconst saqTeacherFeedbackText=\r\n\"Comment:\\n\"+\r\n\"This answer is not correct. 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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Polar Molecules<\/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\/metallic-bonding\/metallic-bonding-and-structure\/\">Metallic Bonding and Structure<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card\">\n        <p><strong>Copyright and author footprint:<\/strong> This OLS revision page was written for Online Learning System by <strong>Dr. Mohammed Al-Fatah<\/strong>. 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