{"id":7677,"date":"2026-09-12T11:56:36","date_gmt":"2026-09-12T10:56:36","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/"},"modified":"2026-09-26T10:24:06","modified_gmt":"2026-09-26T09:24:06","slug":"tetrahedral","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/","title":{"rendered":"Tetrahedral Molecular Shape"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-tetrahedral-molecular-shape-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      --gold: #c9973a;\n      --grey-text: #667085;\n      --body-text: 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border-spacing: 0; }\n      .ols-table thead { display: none; }\n      .ols-table tr { margin-bottom: 14px; border: 1px solid var(--border); border-radius: 18px; overflow: hidden; background: #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    }\n  <\/style>\n\n  <aside class=\"ols-sidebar\">\n  <div class=\"ols-sidebar-header\">\n    <h3>Revision Notes<\/h3>\n    <p>OCR A Level Chemistry A<\/p>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>2.2.2 Bonding and Structure<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/\">Section overview<\/a><\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/ionic-bonding\/\">Ionic Bonding<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/ionic-bonding\/nature-of-ionic-bonding\/\">Nature of Ionic Bonding<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/ionic-bonding\/polarisation-of-ions\/\">Polarisation of Ions<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/ionic-bonding\/physical-properties-of-ionic-compounds\/\">Physical Properties of Ionic Compounds<\/a><\/li>\n        <\/ul>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/covalent-bonding\/\">Covalent Bonding<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/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\/ocr-a\/2-2-2-bonding-and-structure\/covalent-bonding\/dative-covalent-bonding\/\">Dative Covalent Bonding<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/covalent-bonding\/electronegativity\/\">Electronegativity<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/covalent-bonding\/giant-covalent-structures\/\">Giant Covalent Structures<\/a><\/li>\n        <\/ul>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/\">Shapes of Molecules<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/linear\/\">Linear<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/trigonal-planar\/\">Trigonal Planar<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/\">Tetrahedral<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/\">Trigonal Pyramidal<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/bent\/\">Bent<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/trigonal-bipyramidal\/\">Trigonal Bipyramidal<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/octahedral\/\">Octahedral<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/square-planar\/\">Square Planar<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/square-pyramidal\/\">Square Pyramidal<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/distorted-t\/\">Distorted T<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/seesaw\/\">SeeSaw<\/a><\/li>\n        <\/ul>\n      <\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/polar-molecules\/\">Non-Polar and Polar Molecules<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/bond-enthalpy-and-pauling-values\/\">Bond Enthalpy and Pauling Values<\/a><\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/metallic-bonding\/\">Metallic Bonding<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/metallic-bonding\/metallic-bonding-and-structure\/\">Metallic Bonding and Structure<\/a><\/li>\n          <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/metallic-bonding\/physical-properties-of-metals\/\">Physical Properties of Metals<\/a><\/li>\n        <\/ul>\n      <\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/simple-molecular-structures\/\">Simple Molecular Structures<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/structure-types\/\">Structure Types<\/a><\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/\">Intermolecular Forces<\/a>\n        <ul class=\"ols-subtopic-list\">\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/london-forces\/\">London Forces<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/permanent-dipole-dipole-forces\/\">Permanent Dipole-Dipole Forces<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/hydrogen-bonding\/\">Hydrogen Bonding<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/anomalous-properties-of-water\/\">Anomalous Properties of Water<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/boiling-temperature-trends\/\">Boiling Point Trends<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/intermolecular-forces\/choosing-solvents\/\">Choosing Solvents<\/a>\n          <\/li>\n        <\/ul>\n      <\/li>\n    <\/ul>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>Other OCR Sections<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/4-1-1-basic-concepts-of-organic-chemistry\/\">4.1.1 Basic Concepts of Organic Chemistry<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/4-1-2-alkanes\/\">4.1.2 Alkanes<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/4-1-3-alkenes\/\">4.1.3 Alkenes<\/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      .split('?')[0]\r\n      .split('#')[0]\r\n      .replace(\/\\\/+$\/, '')\r\n      .toLowerCase();\r\n  }\r\n\r\n  function highlightActive() {\r\n    var sidebar = document.querySelector('.ols-sidebar');\r\n    if (!sidebar) return false;\r\n\r\n    var currentPath = normalisePath(window.location.pathname);\r\n    var links = 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\/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/\">2.2.2 Bonding and Structure<\/a> \/\n<a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/\">Shapes of Molecules<\/a> \/\n<span>Tetrahedral Molecular Shape<\/span>\n<\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Tetrahedral Molecular Shape<\/h1>\n        <p class=\"ols-page-intro\">A focused revision guide to the tetrahedral molecular shape, using CH<sub>4<\/sub> as the key example. This page explains why four bonding pairs and no lone pairs around a central atom give a three-dimensional tetrahedral arrangement with bond angles of 109.5&deg;.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">Paper 1 and 2<\/div>\n<div class=\"ols-badge\">2.2.2: Bonding and Structure<\/div>\n<div class=\"ols-badge\">H432\/01 and H432\/02<\/div>\n        <\/div>\n\n        <div class=\"ols-author\">\n          <img decoding=\"async\" class=\"ols-author-avatar-img\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\" alt=\"Dr. Mohammed Al-Fatah\">\n          <div class=\"ols-author-content\">\n            <h2 class=\"ols-author-title\">Written by:<br><span>Dr. Mohammed Al-Fatah<\/span><\/h2>\n            <p class=\"ols-author-description\">Chemistry specialist revision notes for A Level Chemistry.<\/p>\n            <a class=\"ols-linkedin-pill\" href=\"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\" target=\"_blank\" rel=\"noopener noreferrer\">\n              <svg class=\"ols-linkedin-icon\" viewBox=\"0 0 24 24\" fill=\"currentColor\" aria-hidden=\"true\"><path d=\"M4.98 3.5C4.98 4.88 3.86 6 2.48 6S0 4.88 0 3.5 1.12 1 2.48 1s2.5 1.12 2.5 2.5zM.5 8h4V24h-4V8zm7 0h3.8v2.2h.1c.5-.9 1.8-2.2 3.9-2.2 4.2 0 5 2.8 5 6.4V24h-4v-7.6c0-1.8 0-4.2-2.6-4.2s-3 2-3 4v7.8h-4V8z\"><\/path><\/svg>\n              View LinkedIn Profile\n            <\/a>\n          <\/div>\n        <\/div>\n      <\/header>\n\n<style>\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-spec-grid {\n    display: grid;\n    grid-template-columns: repeat(3, minmax(0, 1fr));\n    gap: 14px;\n    margin-top: 18px;\n  }\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-spec-box {\n    background: #ffffff;\n    border: 1px solid var(--border);\n    border-radius: 18px;\n    padding: 18px;\n    box-shadow: var(--inner-shadow);\n  }\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-spec-box strong {\n    display: block;\n    font-size: 15px;\n    color: var(--blue);\n    margin-bottom: 6px;\n  }\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-spec-box span {\n    display: block;\n    font-size: 17px;\n    line-height: 1.55;\n    color: var(--body-text);\n    font-weight: 300;\n    overflow-wrap: anywhere;\n  }\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-h5p-grid {\n    display: grid;\n    gap: 18px;\n    margin-top: 22px;\n  }\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-h5p-frame {\n    margin-top: 0;\n  }\n  .ols-tetrahedral-molecular-shape-9ch0-page .ols-formula {\n    white-space: nowrap;\n  }\n  @media (max-width: 760px) {\n    .ols-tetrahedral-molecular-shape-9ch0-page .ols-spec-grid {\n      grid-template-columns: 1fr;\n    }\n  }\n<\/style>\n\n      <section class=\"ols-h5p-card ols-h5p-inline ols-h5p-recap\">\n<span class=\"ols-h5p-kicker\">Before you start<\/span>\n<h2>GCSE Recap: Flat Drawings and 3D Structures<\/h2>\n<p>Before you start, check what you remember about four bonds on one atom and about what a flat drawing can and cannot show.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-content\" data-content-id=\"678\"><\/div><\/div>\n<\/section>\n<article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">1<\/div>\n          <h2>What Tetrahedral Means<\/h2>\n        <\/div>\n        <p>A <strong>tetrahedral<\/strong> molecule has four atoms or groups arranged around a central atom in a three-dimensional shape. The four bonding regions point towards the corners of a tetrahedron.<\/p>\n        <p>The key example for this page is <strong>CH<sub>4<\/sub><\/strong>. Carbon is the central atom and each hydrogen atom is attached to carbon by a covalent bond.<\/p>\n\n        <div class=\"ols-spec-grid\">\n          <div class=\"ols-spec-box\">\n            <strong>Bonding pairs<\/strong>\n            <span>4 bonding pairs around the central atom<\/span>\n          <\/div>\n          <div class=\"ols-spec-box\">\n            <strong>Lone pairs<\/strong>\n            <span>0 lone pairs on the central atom<\/span>\n          <\/div>\n          <div class=\"ols-spec-box\">\n            <strong>Bond angle<\/strong>\n            <span>109.5&deg; between each bond<\/span>\n          <\/div>\n        <\/div>\n\n        <div class=\"ols-key-box\"><p><strong>Key idea:<\/strong> four bonding regions and no lone pairs around a central atom give a tetrahedral shape with 109.5&deg; bond angles.<\/p><\/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>Why CH<sub>4<\/sub> Is Tetrahedral<\/h2>\n        <\/div>\n        <p>In CH<sub>4<\/sub>, the central carbon atom is surrounded by four C-H bonding pairs. These bonding pairs are regions of negative charge, so they repel one another and move as far apart as possible.<\/p>\n        <p>With four equal bonding regions and no lone pairs, the maximum separation is achieved in three dimensions. This gives a <strong>tetrahedral<\/strong> arrangement with H-C-H bond angles of <strong>109.5&deg;<\/strong>.<\/p>\n\n        <div class=\"ols-zoom-card compact\">\n          <div class=\"ols-zoom-card-image\">\n            <img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/wave-59.png\" alt=\"Tetrahedral CH\u2084 drawn with wedge and hash, the 109.5\u00b0 angle marked and a counts panel\" class=\"ols-zoomable-img ols-lightbox-target\" draggable=\"false\">\n          <\/div>\n          <div class=\"ols-zoom-card-caption\">\n            <p>A tetrahedral species has four bonding regions around the central atom and no lone pairs, giving a 109.5&deg; bond angle.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Why Not Flat?<\/h2>\n<p>Drag the words and values into the gaps to explain why four bonding pairs do not lie in one plane.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-184\" class=\"h5p-iframe\" data-content-id=\"184\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Tetrahedral Drag: Why Silane Is Not a Flat Square\"><\/iframe><\/div><\/div>\n<\/section>\n\n<!-- 3D card: ch4-tetrahedral (swapped 26 Sep 2026) -->\n<section class=\"ols-thd-001\" id=\"olsThd001\">\n<style>\n@import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600&display=swap');\n\n.ols-thd-001{\n  font-family:'Poppins',system-ui,-apple-system,'Segoe UI',Roboto,Helvetica,Arial,sans-serif;\n  color:#1C244B; 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padding:4px 8px;}\n  .ols-thd-001 .thd-caption{font-size:10.5px; padding:5px 9px; max-width:64%;}\n  .ols-thd-001 .thd-badge{font-size:10.5px; padding:4px 9px;}\n  .ols-thd-001 .thd-badge.b-shape{font-size:12px;}\n  .ols-thd-001 .thd-badges{max-width:70%;}\n  .ols-thd-001 .thd-info{padding:18px;}\n}\n@media (prefers-reduced-motion:reduce){\n  .ols-thd-001 .thd-seg button,.ols-thd-001 .thd-pill{transition:none;}\n}\n\n.ols-cc-thd-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-thd-001 a{color:#aab0c0; text-decoration:none;}\n.ols-cc-thd-001 a:hover{text-decoration:underline;}\n<\/style>\n\n<div class=\"thd-head\">\n  <h2 class=\"thd-title\">Tetrahedral Shape of CH<sub>4<\/sub><\/h2>\n  <p class=\"thd-sub\">Build methane one layer at a time, from four repelling electron pairs to a three-dimensional molecule with every bond angle 109.5&deg;.<\/p>\n<\/div>\n\n<div class=\"thd-stage\" id=\"thdStage\">\n  <canvas class=\"thd-canvas\" id=\"thdCanvas\"><\/canvas>\n  <div class=\"thd-overlay\" id=\"thdOverlay\"><\/div>\n  <div class=\"thd-caption\" id=\"thdCaption\"><\/div>\n  <div class=\"thd-hint\" id=\"thdHint\">Drag to rotate<\/div>\n  <div class=\"thd-badges\" id=\"thdBadges\"><\/div>\n<\/div>\n\n<div class=\"thd-controls\">\n  <div class=\"thd-row\">\n    <span class=\"thd-rowlab\">Step<\/span>\n    <div class=\"thd-seg\" role=\"group\" aria-label=\"Step\">\n      <button type=\"button\" data-step=\"1\" aria-pressed=\"true\">Electron pairs<\/button>\n      <button type=\"button\" data-step=\"2\" aria-pressed=\"false\">Bonds<\/button>\n      <button type=\"button\" data-step=\"3\" aria-pressed=\"false\">Bond angles<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"thd-row\">\n    <span class=\"thd-rowlab\">View<\/span>\n    <div class=\"thd-seg\" role=\"group\" aria-label=\"Camera view\">\n      <button type=\"button\" data-v=\"front\" aria-pressed=\"false\">Front<\/button>\n      <button type=\"button\" data-v=\"side\" aria-pressed=\"false\">Side<\/button>\n      <button type=\"button\" data-v=\"top\" aria-pressed=\"false\">Top<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"thd-row\">\n    <span class=\"thd-rowlab\">Show<\/span>\n    <button type=\"button\" class=\"thd-pill is-off\" id=\"thdTogLp\" aria-pressed=\"false\" aria-disabled=\"true\" title=\"CH&#8324; has no lone pairs\"><i class=\"dot\"><\/i>Lone pairs<\/button>\n    <button type=\"button\" class=\"thd-pill p-gold\" id=\"thdTogAng\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Bond angles<\/button>\n    <button type=\"button\" class=\"thd-pill\" id=\"thdTogLab\" aria-pressed=\"true\"><i class=\"dot\"><\/i>Labels<\/button>\n    <button type=\"button\" class=\"thd-pill\" id=\"thdTogCloud\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Electron-pair cloud outline<\/button>\n    <button type=\"button\" class=\"thd-pill\" id=\"thdTogTet\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Show tetrahedron<\/button>\n  <\/div>\n\n  <div class=\"thd-row\">\n    <span class=\"thd-rowlab\">Motion<\/span>\n    <button type=\"button\" class=\"thd-pill\" id=\"thdSpin\" aria-pressed=\"false\"><i class=\"dot\"><\/i>Rotation<\/button>\n    <button type=\"button\" class=\"thd-pill\" id=\"thdResetV\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"thd-info\">\n  <h3 id=\"thdInfoTitle\"><\/h3>\n  <p id=\"thdInfoText\"><\/p>\n  <div class=\"thd-facts\" id=\"thdFacts\"><\/div>\n  <div class=\"thd-key\">\n    <span><i style=\"background:rgba(59,120,220,0.45)\"><\/i>Electron pair<\/span>\n    <span><i style=\"background:#484e5c\"><\/i>Carbon, central atom<\/span>\n    <span><i style=\"background:#eef0f5\"><\/i>Hydrogen<\/span>\n    <span><i style=\"background:#8c92a0\"><\/i>Bond<\/span>\n    <span><i style=\"background:#c9961c\"><\/i>Bond angle<\/span>\n    <span><i style=\"background:rgba(28,36,75,0.06); border:1.5px dashed rgba(28,36,75,0.6)\"><\/i>Tetrahedron<\/span>\n  <\/div>\n<\/div>\n<\/section>\n\n<p class=\"ols-cc-thd-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\/ch4-tetrahedral.js?v=20260926\"><\/script>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">3<\/div>\n          <h2>Bonding Pairs, Lone Pairs and Bond Angle<\/h2>\n        <\/div>\n        <p>The shape is decided by the number of electron domains around the central atom. In a simple molecular shape question, each single bond counts as one bonding region. CH<sub>4<\/sub> has four bonding regions around carbon and no lone pair regions on carbon.<\/p>\n\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Feature<\/th>\n                <th>Tetrahedral value<\/th>\n                <th>Meaning in CH<sub>4<\/sub><\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Feature\">Number of bonding pairs<\/td>\n                <td data-label=\"Tetrahedral value\">4<\/td>\n                <td data-label=\"Meaning in CH4\">Four C-H bonding pairs repel each other equally.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Feature\">Number of lone pairs<\/td>\n                <td data-label=\"Tetrahedral value\">0<\/td>\n                <td data-label=\"Meaning in CH4\">No lone pair compression occurs, so the ideal tetrahedral angle is maintained.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Feature\">Bond angle<\/td>\n                <td data-label=\"Tetrahedral value\">109.5&deg;<\/td>\n                <td data-label=\"Meaning in CH4\">The four bonds are arranged as far apart as possible in three-dimensional space.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Feature\">Molecular shape<\/td>\n                <td data-label=\"Tetrahedral value\">Tetrahedral<\/td>\n                <td data-label=\"Meaning in CH4\">The surrounding atoms point towards the corners of a tetrahedron.<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Count the Pairs<\/h2>\n<p>Work out the electron count for two species with four bonded atoms and type each answer.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-186\" class=\"h5p-iframe\" data-content-id=\"186\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Tetrahedral Flashcards: Counting Electron Pairs in BH\u2084\u207b and TeBr\u2084\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">4<\/div>\n          <h2>Examples of Tetrahedral Species<\/h2>\n        <\/div>\n        <p>Several molecules and ions use the same four-region arrangement around the central atom. The examples from this shape table include <strong>SiCl<sub>4<\/sub><\/strong>, <strong>SO<sub>4<\/sub><sup>2-<\/sup><\/strong>, <strong>ClO<sub>4<\/sub><sup>&#8211;<\/sup><\/strong> and <strong>NH<sub>4<\/sub><sup>+<\/sup><\/strong>.<\/p>\n        <p>For exam purposes, focus on the central atom, count the electron domains around it, then state the shape and bond angle.<\/p>\n\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Species<\/th>\n                <th>Central atom<\/th>\n                <th>Electron regions around central atom<\/th>\n                <th>Shape<\/th>\n                <th>Bond angle<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Species\">CH<sub>4<\/sub><\/td>\n                <td data-label=\"Central atom\">C<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 0 lone pairs<\/td>\n                <td data-label=\"Shape\">Tetrahedral<\/td>\n                <td data-label=\"Bond angle\">109.5&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">SiCl<sub>4<\/sub><\/td>\n                <td data-label=\"Central atom\">Si<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 0 lone pairs<\/td>\n                <td data-label=\"Shape\">Tetrahedral<\/td>\n                <td data-label=\"Bond angle\">109.5&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">SO<sub>4<\/sub><sup>2-<\/sup><\/td>\n                <td data-label=\"Central atom\">S<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 0 lone pairs<\/td>\n                <td data-label=\"Shape\">Tetrahedral<\/td>\n                <td data-label=\"Bond angle\">109.5&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">ClO<sub>4<\/sub><sup>&#8211;<\/sup><\/td>\n                <td data-label=\"Central atom\">Cl<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 0 lone pairs<\/td>\n                <td data-label=\"Shape\">Tetrahedral<\/td>\n                <td data-label=\"Bond angle\">109.5&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">NH<sub>4<\/sub><sup>+<\/sup><\/td>\n                <td data-label=\"Central atom\">N<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 0 lone pairs<\/td>\n                <td data-label=\"Shape\">Tetrahedral<\/td>\n                <td data-label=\"Bond angle\">109.5&deg;<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <\/article>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: Which Are Tetrahedral?<\/h2>\n<p>Count the electrons left over on each central atom, then click every species that is tetrahedral.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-185\" class=\"h5p-iframe\" data-content-id=\"185\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Tetrahedral Mark the Words: Which Species Are Tetrahedral?\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card orange\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">5<\/div>\n          <h2>How to Explain Tetrahedral Shape in an Exam<\/h2>\n        <\/div>\n        <p>A full exam explanation should name the electron pairs around the central atom and connect this directly to repulsion and angle.<\/p>\n\n        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>1. Identify the central atom<\/h3>\n            <p>For CH<sub>4<\/sub>, the central atom is carbon.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>2. Count bonding pairs and lone pairs<\/h3>\n            <p>Carbon has four bonding pairs and no lone pairs around it.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>3. Apply electron-pair repulsion<\/h3>\n            <p>The four bonding pairs repel equally and move as far apart as possible.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>4. State the shape and angle<\/h3>\n            <p>The molecule is tetrahedral with bond angles of 109.5&deg;.<\/p>\n          <\/div>\n        <\/div>\n\n        <div class=\"ols-definition-box\">\n          <p><strong>Exam answer model:<\/strong> CH<sub>4<\/sub> has four bonding pairs and no lone pairs around the central carbon atom. The bonding pairs repel equally and arrange themselves as far apart as possible in three-dimensional space. Therefore, CH<sub>4<\/sub> is tetrahedral with bond angles of 109.5&deg;.<\/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: Whose Reasoning Is Right?<\/h2>\n<p>In each round, choose the one student statement that an examiner would accept.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-187\" class=\"h5p-iframe\" data-content-id=\"187\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Tetrahedral Summary: Whose Reasoning Is Right?\"><\/iframe><\/div><\/div>\n<\/section>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">6<\/div>\n          <h2>Common Exam Points<\/h2>\n        <\/div>\n        <p>Tetrahedral questions often test whether you can distinguish a four-domain arrangement from trigonal planar or shapes affected by lone pairs.<\/p>\n        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>Do not write 120&deg;<\/h3>\n            <p>120&deg; is the trigonal planar angle. Tetrahedral species have four electron regions and an ideal angle of 109.5&deg;.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Do not flatten the shape<\/h3>\n            <p>Tetrahedral molecules are three-dimensional, not planar. Wedge and dashed bonds are often used to show this 3D arrangement.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Check for lone pairs<\/h3>\n            <p>Four bonding pairs and no lone pairs gives tetrahedral. If lone pairs are present, the molecular shape and bond angle may change.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Use electron-pair repulsion language<\/h3>\n            <p>Marks usually require the idea that bonding pairs repel and arrange themselves as far apart as possible.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n\n      \n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">\u2713<\/div>\n          <h2>QuickSnap<\/h2>\n        <\/div>\n        <p>The tetrahedral shape is produced when a central atom has <strong>four bonding pairs<\/strong> and <strong>no lone pairs<\/strong>. The bonding pairs repel equally and spread out in three-dimensional space, giving <strong>109.5&deg;<\/strong> bond angles.<\/p>\n        <div class=\"ols-key-box\"><p><strong>Memory line:<\/strong> 4 bonding pairs + 0 lone pairs = tetrahedral = 109.5&deg;.<\/p><\/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 .ols-course-cta-card {\r\n      overflow: 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border: 0;\r\n      background: transparent;\r\n      box-shadow: none;\r\n      padding: 0;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-course-animation-title {\r\n      margin: 0 0 18px;\r\n      text-align: center;\r\n      color: var(--navy);\r\n      font-size: clamp(26px, 3.2vw, 40px);\r\n      line-height: 1.15;\r\n      font-weight: 700;\r\n      letter-spacing: -0.03em;\r\n      text-shadow: -9px 0 9px rgba(28, 36, 75, 0.10);\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-frame-shell {\r\n      position: relative;\r\n      width: 100%;\r\n      height: 620px;\r\n      border-radius: 24px;\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      box-shadow: 0 24px 64px rgba(28, 36, 75, 0.18);\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-frame-shell iframe {\r\n      display: block;\r\n      width: 100%;\r\n      height: 100%;\r\n      border: 0;\r\n      background: #e9efff;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-start-overlay {\r\n      position: absolute;\r\n      inset: 0;\r\n      z-index: 5;\r\n      display: flex;\r\n      align-items: center;\r\n      justify-content: center;\r\n      border: 0;\r\n      cursor: pointer;\r\n      background:\r\n        radial-gradient(circle at center, rgba(255, 255, 255, 0.26), rgba(28, 36, 75, 0.28)),\r\n        url(\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/09\/ocr-a-level-chemistry-a-2-2-2-covalent-bonding-shapes-interactive-course-banner.jpg\");\r\n      background-size: cover;\r\n      background-position: center;\r\n      transition:\r\n        opacity 0.35s ease,\r\n        visibility 0.35s ease;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-start-overlay::before {\r\n      content: \"\";\r\n      position: absolute;\r\n      inset: 0;\r\n      background: rgba(28, 36, 75, 0.30);\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-start-overlay.is-hidden {\r\n      opacity: 0;\r\n      visibility: hidden;\r\n      pointer-events: none;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-start-content {\r\n      position: relative;\r\n      z-index: 2;\r\n      display: grid;\r\n      justify-items: center;\r\n      gap: 16px;\r\n      padding: 24px;\r\n      text-align: center;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-play-circle {\r\n      width: 96px;\r\n      height: 96px;\r\n      border-radius: 50%;\r\n      background: #ffffff;\r\n      color: var(--navy);\r\n      display: flex;\r\n      align-items: center;\r\n      justify-content: center;\r\n      box-shadow:\r\n        0 18px 40px rgba(28, 36, 75, 0.30),\r\n        0 0 0 12px rgba(255, 255, 255, 0.22);\r\n      animation: olsAnimationPlayPulse001 1.8s ease-in-out infinite;\r\n      transition:\r\n        transform 0.25s ease,\r\n        background 0.25s ease,\r\n        color 0.25s ease;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-start-overlay:hover .ols-animation-play-circle {\r\n      transform: scale(1.08);\r\n      background: var(--navy);\r\n      color: #ffffff;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-play-icon {\r\n      width: 0;\r\n      height: 0;\r\n      margin-left: 7px;\r\n      border-top: 18px solid transparent;\r\n      border-bottom: 18px solid transparent;\r\n      border-left: 28px solid currentColor;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-start-text {\r\n      max-width: 540px;\r\n      margin: 0;\r\n      color: #ffffff;\r\n      font-size: clamp(20px, 3vw, 32px);\r\n      line-height: 1.2;\r\n      font-weight: 800;\r\n      text-shadow: 0 8px 20px rgba(0, 0, 0, 0.28);\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-pause-button {\r\n      position: absolute;\r\n      left: 16px;\r\n      bottom: 16px;\r\n      z-index: 7;\r\n      display: none;\r\n      align-items: center;\r\n      justify-content: center;\r\n      min-width: 92px;\r\n      padding: 10px 16px;\r\n      border: 0;\r\n      border-radius: 999px;\r\n      background: rgba(28, 36, 75, 0.92);\r\n      color: #ffffff;\r\n      font-family: Poppins, Arial, sans-serif;\r\n      font-size: 14px;\r\n      line-height: 1.2;\r\n      font-weight: 800;\r\n      cursor: pointer;\r\n      box-shadow: 0 12px 28px rgba(28, 36, 75, 0.24);\r\n      transition:\r\n        transform 0.2s ease,\r\n        background 0.2s ease,\r\n        box-shadow 0.2s ease;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-pause-button:hover {\r\n      transform: translateY(-2px);\r\n      background: var(--blue);\r\n      box-shadow: 0 16px 34px rgba(37, 99, 235, 0.28);\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-animation-pause-button.is-visible {\r\n      display: inline-flex;\r\n    }\r\n\r\n    @keyframes olsAnimationPlayPulse001 {\r\n      0% {\r\n      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justify-content: center;\r\n      padding: 15px 28px;\r\n      border-radius: 999px;\r\n      background: var(--navy);\r\n      color: #ffffff;\r\n      text-decoration: none;\r\n      font-size: 16px;\r\n      line-height: 1.2;\r\n      font-weight: 800;\r\n      box-shadow: 0 12px 26px rgba(28, 36, 75, 0.18);\r\n      transition:\r\n        transform 0.2s ease,\r\n        background 0.2s ease,\r\n        box-shadow 0.2s ease;\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-course-button:hover {\r\n      transform: translateY(-2px);\r\n      background: var(--blue);\r\n      color: #ffffff;\r\n      box-shadow: 0 16px 32px rgba(37, 99, 235, 0.24);\r\n    }\r\n\r\n    .ols-course-cta-covalent .ols-course-button-top {\r\n      flex-shrink: 0;\r\n      padding: 12px 22px;\r\n      font-size: 15px;\r\n    }\r\n\r\n    @media (max-width: 900px) {\r\n      .ols-course-cta-covalent .ols-course-cta-top {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-cta-image-link {\r\n        max-width: 520px;\r\n        margin: 0 auto;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-cta-intro-stats {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-covalent .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-covalent {\r\n        margin: 26px 0 22px;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-cta-card {\r\n        padding: 20px;\r\n        border-radius: 24px;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-cta-header-row {\r\n        align-items: stretch;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-button-top {\r\n        width: 100%;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-cta-stats,\r\n      .ols-course-cta-covalent .ols-course-cta-features {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-course-animation-wrap {\r\n        padding: 0;\r\n        border-radius: 0;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-animation-frame-shell {\r\n        height: 420px;\r\n        border-radius: 18px;\r\n      }\r\n\r\n      .ols-course-cta-covalent .ols-animation-play-circle {\r\n        width: 76px;\r\n        height: 76px;\r\n      }\r\n\r\n      .ols-course-cta-covalent .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-covalent .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-covalent .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\/covalent-bonding-and-shapes-of-molecules-2-2-2-ocr-a\/\" aria-label=\"Open the OCR A Level Chemistry A 2.2.2 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\/ocr-a-level-chemistry-a-2-2-2-covalent-bonding-shapes-interactive-course-banner.jpg\"\r\n            alt=\"OCR A Level Chemistry A 2.2.2 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            OCR H432 | 2.2.2 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-2-2-2-ocr-a\/\">\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 OCR A Level Chemistry A\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 2.2.2 Covalent Bonding and Shapes of Molecules course. The guided video lessons are ready now; the OCR A 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 2.2.2 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-2-2-2-ocr-a\/\">\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  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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  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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 class=\"ols-saq-intro-title-wrap\">\r\n          <h1 class=\"ols-saq-intro-title\">\r\n            <span id=\"saqIntroTitleText\"><\/span><span id=\"saqIntroTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <div class=\"ols-saq-scale-wrap\">\r\n        <main id=\"saqScreen\" class=\"ols-saq-screen\">\r\n          <section class=\"saq-question-area\">\r\n            <div class=\"saq-question-text\">\r\n              <strong>(ii)<\/strong>&nbsp;&nbsp; Melting temperature depends on the strength of metallic bonding.<br>\r\n              Explain why the metallic bonding in magnesium is much stronger than that in sodium.\r\n            <\/div>\r\n\r\n            <div class=\"saq-student-box\">\r\n              <span id=\"saqStudentText\"><\/span><span id=\"saqStudentCursor\" class=\"cursor\"><\/span>\r\n            <\/div>\r\n          <\/section>\r\n\r\n          <section id=\"saqTeacherFeedback\" 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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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The bonding pairs repel equally and arrange themselves as far apart as possible in three-dimensional space.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Why is CH<sub>4<\/sub> tetrahedral?<\/h3>\n            <p>CH<sub>4<\/sub> has four C-H bonding pairs around the central carbon atom and no lone pairs on carbon. The four bonding pairs repel equally, so the molecule is tetrahedral with 109.5&deg; bond angles.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>What is the bond angle in a tetrahedral molecule?<\/h3>\n            <p>The ideal bond angle in a tetrahedral molecule is 109.5&deg;.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Is a tetrahedral molecule flat?<\/h3>\n            <p>No. A tetrahedral molecule is three-dimensional. The bonds point towards the corners of a tetrahedron rather than lying in one flat plane.<\/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 tetrahedral shape with the wider bonding and structure topic.<\/p>\n        <div class=\"ols-related-grid\">\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/covalent-bonding\/\">Covalent Bonding &amp; Structure<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/covalent-bonding\/electronegativity\/\">Electronegativity<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/linear\/\">Linear<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/trigonal-planar\/\">Trigonal Planar<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/\">Trigonal Pyramidal<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/polar-molecules\/\">Polar &amp; Non-Polar Molecules<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card\">\n        <p><strong>&copy; Online Learning System.<\/strong> This revision page was written and produced for OLS by Dr. Mohammed Al-Fatah. All diagrams, explanations, interactive cards and revision resources on this page are protected by copyright and are provided for student revision and teaching use only.<\/p>\n      <\/section>\n\n      <script type=\"application\/ld+json\">{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"WebPage\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/#webpage\",\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/\",\n      \"name\": \"Tetrahedral Molecular Shape | OCR A Level Chemistry A\",\n      \"description\": \"A Level Chemistry revision notes explaining the tetrahedral molecular shape, CH4, electron-pair repulsion, four bonding pairs, no lone pairs and 109.5 degree bond angles.\",\n      \"isPartOf\": {\n        \"@type\": \"WebSite\",\n        \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/#website\",\n        \"name\": \"Online Learning System\",\n        \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/\"\n      },\n      \"about\": {\n        \"@type\": \"Thing\",\n        \"name\": \"Tetrahedral molecular shape\"\n      },\n      \"inLanguage\": \"en-GB\"\n    },\n    {\n      \"@type\": \"BreadcrumbList\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/#breadcrumb\",\n      \"itemListElement\": [\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 1,\n          \"name\": \"Revision Notes\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 2,\n          \"name\": \"A Level Chemistry\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 3,\n          \"name\": \"OCR A\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 4,\n          \"name\": \"2.2.2 Bonding and Structure\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 5,\n          \"name\": \"Shapes of Molecules\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 6,\n          \"name\": \"Tetrahedral Molecular Shape\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/\"\n        }\n      ]\n    },\n    {\n      \"@type\": \"Course\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/product\/covalent-bonding-shapes-of-molecules-edexcel-t2ab\/#course\",\n      \"name\": \"Covalent Bonding, Structure and Shapes of Molecules\",\n      \"description\": \"A paid OLS course covering covalent bonding, structure, molecular shapes, electron-pair repulsion, bond angles and exam-style practice for OCR A Level Chemistry A.\",\n      \"provider\": {\n        \"@type\": \"Organization\",\n        \"name\": \"Online Learning System\",\n        \"sameAs\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/\"\n      },\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/product\/covalent-bonding-shapes-of-molecules-edexcel-t2ab\/\"\n    },\n    {\n      \"@type\": \"FAQPage\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/2-2-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/#faq\",\n      \"mainEntity\": [\n        {\n          \"@type\": \"Question\",\n          \"name\": \"What makes a molecule tetrahedral?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"A molecule is tetrahedral when the central atom has four bonding regions and no lone pairs. The bonding pairs repel equally and arrange themselves as far apart as possible in three-dimensional space.\"\n          }\n        },\n        {\n          \"@type\": \"Question\",\n          \"name\": \"Why is CH4 tetrahedral?\",\n          \"acceptedAnswer\": {\n            \"@type\": \"Answer\",\n            \"text\": \"CH4 has four C-H bonding pairs around the central carbon atom and no lone pairs on carbon. 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This page explains why four bonding pairs and no lone pairs around a central atom [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":7674,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-7677","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/7677","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/comments?post=7677"}],"version-history":[{"count":3,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/7677\/revisions"}],"predecessor-version":[{"id":10361,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/7677\/revisions\/10361"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/7674"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=7677"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}