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{ 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\">\r\n  <div class=\"ols-sidebar-header\">\r\n    <h3>Revision Notes<\/h3>\r\n    <p>A Level Chemistry<\/p>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Topic 2 Bonding and Structure<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/\">Ionic Bonding<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/nature-of-ionic-bonding\/\">Nature of Ionic Bonding<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/polarisation-of-ions\/\">Polarisation of Ions<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/ionic-bonding\/physical-properties-of-ionic-compounds\/\">Physical Properties of Ionic Compounds<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/\">Covalent Bonding<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/nature-of-covalent-bonding\/\">Nature of Covalent Bonding<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/dative-covalent-bonding\/\">Dative Covalent Bonding<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/electronegativity\/\">Electronegativity<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/\">Shapes of Molecules<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/linear\/\">Linear<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-planar\/\">Trigonal Planar<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/tetrahedral\/\">Tetrahedral<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/\">Trigonal Pyramidal<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/bent\/\">Bent<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-bipyramidal\/\">Trigonal Bipyramidal<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/octahedral\/\">Octahedral<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/square-planar\/\">Square Planar<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/square-pyramidal\/\">Square Pyramidal<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/distorted-t\/\">Distorted T<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/seesaw\/\">SeeSaw<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/polar-molecules\/\">Polar Molecules<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/\">Metallic Bonding<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/metallic-bonding-and-structure\/\">Metallic Bonding and Structure<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/metallic-bonding\/physical-properties-of-metals\/\">Physical Properties of Metals<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/intermolecular-forces\/\">Intermolecular Forces<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/structure-types\/\">Structure Types<\/a>\r\n      <\/li>\r\n\r\n    <\/ul>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Next Topics<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-3-redox-i\/\">Redox I<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\">Inorganic Chemistry &amp; The Periodic Table<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/\">Formulae, Equations &amp; Amounts<\/a>\r\n      <\/li>\r\n    <\/ul>\r\n  <\/div>\r\n<\/aside>\r\n\r\n<script>\r\n(function() {\r\n  function normalisePath(path) {\r\n    return String(path || '')\r\n      .split('?')[0]\r\n      .split('#')[0]\r\n      .replace(\/\\\/+$\/, '')\r\n      .toLowerCase();\r\n  }\r\n\r\n  function highlightActive() {\r\n    var sidebar = document.querySelector('.ols-sidebar');\r\n    if (!sidebar) return false;\r\n\r\n    var currentPath = normalisePath(window.location.pathname);\r\n    var links = sidebar.querySelectorAll('a[href]');\r\n    var matched = null;\r\n    var matchedLength = 0;\r\n\r\n    sidebar.querySelectorAll('.active, .active-main, .parent-active').forEach(function(item) {\r\n      item.classList.remove('active', 'active-main', 'parent-active');\r\n    });\r\n\r\n    sidebar.querySelectorAll('a[data-ols-disabled-parent=\"1\"], a[aria-current]').forEach(function(a) {\r\n      a.removeAttribute('aria-current');\r\n      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class=\"ols-breadcrumbs\" aria-label=\"Breadcrumb\">\n        <a 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\/edexcel\/\">Edexcel<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/\">Topic 2 Bonding and Structure<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/\">Shapes of Molecules<\/a> \/\n        <span>SeeSaw<\/span>\n      <\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>SeeSaw Molecular Shape<\/h1>\n        <p class=\"ols-page-intro\">A focused revision guide to the SeeSaw molecular shape, using SF<sub>4<\/sub> as the key example. This page explains why four bonding pairs and one lone pair around a central atom give a SeeSaw arrangement with bond angles close to 119&deg; and 89&deg; in simplified exam tables.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">Unit: Paper 1<\/div>\n          <div class=\"ols-badge\">Topic 2: Bonding and Structure<\/div>\n          <div class=\"ols-badge\">9CH0\/01<\/div>\n        <\/div>\n\n        <div class=\"ols-author\">\n          <img decoding=\"async\" class=\"ols-author-avatar-img\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\" alt=\"Dr. Mohammed Al-Fatah\">\n          <div class=\"ols-author-content\">\n            <h2 class=\"ols-author-title\">Written by:<br><span>Dr. Mohammed Al-Fatah<\/span><\/h2>\n            <p class=\"ols-author-description\">Chemistry specialist revision notes for A Level Chemistry.<\/p>\n            <a class=\"ols-linkedin-pill\" href=\"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\" target=\"_blank\" rel=\"noopener noreferrer\">\n              <svg class=\"ols-linkedin-icon\" viewBox=\"0 0 24 24\" fill=\"currentColor\" aria-hidden=\"true\"><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-seesaw-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-seesaw-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-seesaw-9ch0-page .ols-spec-box strong {\n    display: block;\n    font-size: 15px;\n    color: var(--blue);\n    margin-bottom: 6px;\n  }\n  .ols-seesaw-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-seesaw-9ch0-page .ols-h5p-grid {\n    display: grid;\n    gap: 18px;\n    margin-top: 22px;\n  }\n  .ols-seesaw-9ch0-page .ols-h5p-frame {\n    margin-top: 0;\n  }\n  .ols-seesaw-9ch0-page .ols-formula {\n    white-space: nowrap;\n  }\n  .ols-seesaw-9ch0-page .ols-seesaw-reference-figure .ols-figure-image {\n    min-height: 0;\n    padding: 12px;\n  }\n  .ols-seesaw-9ch0-page .ols-seesaw-reference-figure .ols-figure-image img {\n    width: auto;\n    max-width: 100%;\n    max-height: 320px;\n    object-fit: contain;\n    margin: 0 auto;\n  }\n  @media (max-width: 760px) {\n    .ols-seesaw-9ch0-page .ols-spec-grid {\n      grid-template-columns: 1fr;\n    }\n  }\n<\/style>\n\n<style>\n  .ols-seesaw-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-seesaw-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-seesaw-9ch0-page .ols-spec-box strong {\n    display: block;\n    font-size: 15px;\n    color: var(--blue);\n    margin-bottom: 6px;\n  }\n  .ols-seesaw-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-seesaw-9ch0-page .ols-h5p-grid {\n    display: grid;\n    gap: 18px;\n    margin-top: 22px;\n  }\n  .ols-seesaw-9ch0-page .ols-h5p-frame {\n    margin-top: 0;\n  }\n  .ols-seesaw-9ch0-page .ols-formula {\n    white-space: nowrap;\n  }\n  .ols-seesaw-9ch0-page .ols-seesaw-reference-figure .ols-figure-image {\n    min-height: 0;\n    padding: 12px;\n  }\n  .ols-seesaw-9ch0-page .ols-seesaw-reference-figure .ols-figure-image img {\n    width: auto;\n    max-width: 100%;\n    max-height: 320px;\n    object-fit: contain;\n    margin: 0 auto;\n  }\n  @media (max-width: 760px) {\n    .ols-seesaw-9ch0-page .ols-spec-grid {\n      grid-template-columns: 1fr;\n    }\n  }\n<\/style>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">1<\/div>\n          <h2>What SeeSaw Means<\/h2>\n        <\/div>\n        <p>A <strong>SeeSaw<\/strong> molecule has four atoms bonded to a central atom, with the bonded atoms arranged like a tilted seesaw. The shape forms when there are <strong>four bonding pairs<\/strong> and <strong>one lone pair<\/strong> around the central atom.<\/p>\n        <p>The key example for this page is <strong>SF<sub>4<\/sub><\/strong>. Sulfur is the central atom, four fluorine atoms are bonded to sulfur, and sulfur also has one lone pair.<\/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>1 lone pair on the central atom<\/span>\n          <\/div>\n          <div class=\"ols-spec-box\">\n            <strong>Bond angles<\/strong>\n            <span>Approximately 119&deg; and 89&deg; in simplified exam tables<\/span>\n          <\/div>\n        <\/div>\n\n        <div class=\"ols-key-box\"><p><strong>Key idea:<\/strong> four bonding pairs and one lone pair around a central atom give a SeeSaw shape when the lone pair occupies an equatorial position in a trigonal bipyramidal electron-pair arrangement.<\/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 SF<sub>4<\/sub> Is SeeSaw-Shaped<\/h2>\n        <\/div>\n        <p>In SF<sub>4<\/sub>, the central sulfur atom is surrounded by four S-F bonding pairs and one lone pair. This gives five regions of negative charge around sulfur.<\/p>\n        <p>Five electron regions arrange themselves as a <strong>trigonal bipyramidal electron-pair arrangement<\/strong> to minimise repulsion. The lone pair occupies an equatorial position because this gives fewer 90&deg; lone-pair interactions than placing it in an axial position.<\/p>\n        <p>The <strong>molecular shape<\/strong> only describes the positions of the atoms. Therefore, SF<sub>4<\/sub> is described as <strong>SeeSaw-shaped<\/strong>, even though its electron-pair arrangement is trigonal bipyramidal.<\/p>\n\n        <div class=\"ols-figure-card compact ols-seesaw-reference-figure ols-zoom-figure\">\n          <button class=\"ols-figure-image ols-lightbox-trigger\" type=\"button\" data-ols-lightbox-src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/seesaw.webp\" data-ols-lightbox-alt=\"SeeSaw molecular shape table entry showing four bonding pairs, one lone pair, bond angles close to 119 and 89 degrees and examples including SF4, SeF4, TeF4, IF4 plus and ClF4 plus\" aria-label=\"Open seesaw diagram in full screen\">\n            <img decoding=\"async\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/seesaw.webp\" alt=\"SeeSaw molecular shape table entry showing four bonding pairs, one lone pair, bond angles close to 119 and 89 degrees and examples including SF4, SeF4, TeF4, IF4 plus and ClF4 plus\">\n          <\/button>\n          <div class=\"ols-figure-caption\">\n            <p>A SeeSaw species has four bonding regions and one lone pair around the central atom. SF<sub>4<\/sub> is the standard example, with simplified exam-table angles close to 119&deg; and 89&deg;.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n\n<section id=\"ols-sf4-seesaw-card\" class=\"ols-sf4-seesaw-card\">\n  <style>\n    #ols-sf4-seesaw-card {\n      --ols-navy: #1C244B;\n      --ols-gold: #c9973a;\n      --ols-red: #c81e1e;\n      --ols-green: #31a36a;\n      --ols-blue: #1f7ae0;\n      --ols-soft-blue: #EEF4FF;\n      --ols-border: rgba(28, 36, 75, 0.14);\n      --ols-shadow: 0 14px 34px rgba(28, 36, 75, 0.12);\n      font-family: Poppins, Arial, sans-serif;\n      color: var(--ols-navy);\n      width: 100%;\n      margin: 28px auto;\n    }\n\n    #ols-sf4-seesaw-card * {\n      box-sizing: border-box;\n    }\n\n    #ols-sf4-seesaw-card .ols-model-card {\n      width: 100%;\n      background: linear-gradient(180deg, #ffffff 0%, #f8fbff 100%);\n      border: 1px solid var(--ols-border);\n      border-radius: 28px;\n      box-shadow: var(--ols-shadow);\n  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75, 0.14);\n      border: 1px solid rgba(28, 36, 75, 0.08);\n      pointer-events: none;\n      z-index: 4;\n    }\n\n    #ols-sf4-seesaw-card .ols-angle-badge {\n      position: absolute;\n      left: 16px;\n      bottom: 16px;\n      background: rgba(255, 255, 255, 0.94);\n      color: var(--ols-navy);\n      padding: 8px 12px;\n      border-radius: 999px;\n      font-size: 13px;\n      font-weight: 700;\n      box-shadow: 0 6px 18px rgba(28, 36, 75, 0.14);\n      border: 1px solid rgba(28, 36, 75, 0.08);\n      pointer-events: none;\n      z-index: 4;\n    }\n\n    #ols-sf4-seesaw-card .ols-controls {\n      display: flex;\n      flex-wrap: wrap;\n      gap: 10px;\n      padding: 16px 18px;\n      background: #ffffff;\n      border-top: 1px solid rgba(28, 36, 75, 0.08);\n    }\n\n    #ols-sf4-seesaw-card .ols-btn {\n      appearance: none;\n      border: 1px solid rgba(28, 36, 75, 0.14);\n      background: #ffffff;\n      color: var(--ols-navy);\n      border-radius: 999px;\n      padding: 10px 15px;\n      font-family: Poppins, Arial, sans-serif;\n      font-size: 14px;\n      font-weight: 600;\n      cursor: pointer;\n      transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease, color 0.2s ease;\n    }\n\n    #ols-sf4-seesaw-card .ols-btn:hover {\n      transform: translateY(-2px);\n      box-shadow: 0 8px 20px rgba(28, 36, 75, 0.12);\n    }\n\n    #ols-sf4-seesaw-card .ols-btn.is-active {\n      background: var(--ols-navy);\n      color: #ffffff;\n      border-color: var(--ols-navy);\n    }\n\n    #ols-sf4-seesaw-card .ols-explanation {\n      padding: 22px 26px 26px;\n      background: #ffffff;\n      border-top: 1px solid rgba(28, 36, 75, 0.08);\n    }\n\n    #ols-sf4-seesaw-card .ols-key-message {\n      margin: 0;\n      padding: 16px 18px;\n      border-radius: 18px;\n      background: var(--ols-soft-blue);\n      border: 1px solid rgba(31, 122, 224, 0.14);\n      font-size: 16px;\n      line-height: 1.65;\n      font-weight: 300;\n      color: rgba(28, 36, 75, 0.88);\n    }\n\n    #ols-sf4-seesaw-card .ols-key-message strong {\n      font-weight: 700;\n      color: var(--ols-navy);\n    }\n\n    #ols-sf4-seesaw-card .ols-explanation-grid {\n      display: grid;\n      grid-template-columns: repeat(3, minmax(0, 1fr));\n      gap: 14px;\n      margin-top: 16px;\n    }\n\n    #ols-sf4-seesaw-card .ols-info-box {\n      border-radius: 18px;\n      padding: 16px;\n      background: #f8fbff;\n      border: 1px solid rgba(28, 36, 75, 0.1);\n    }\n\n    #ols-sf4-seesaw-card .ols-info-box strong {\n      display: block;\n      font-size: 15px;\n      margin-bottom: 6px;\n      color: var(--ols-navy);\n    }\n\n    #ols-sf4-seesaw-card .ols-info-box span {\n      display: block;\n      font-size: 14px;\n      line-height: 1.55;\n      font-weight: 300;\n      color: rgba(28, 36, 75, 0.8);\n    }\n\n    @media (max-width: 820px) {\n      #ols-sf4-seesaw-card .ols-viewer-wrap {\n        height: 500px;\n      }\n\n      #ols-sf4-seesaw-card .ols-explanation-grid {\n        grid-template-columns: 1fr;\n      }\n\n      #ols-sf4-seesaw-card .ols-viewer-badge {\n        top: 12px;\n        right: 12px;\n        font-size: 12px;\n      }\n    }\n\n    @media (max-width: 520px) {\n      #ols-sf4-seesaw-card .ols-model-header,\n      #ols-sf4-seesaw-card .ols-explanation {\n        padding-left: 18px;\n        padding-right: 18px;\n      }\n\n      #ols-sf4-seesaw-card .ols-viewer-wrap {\n        height: 430px;\n      }\n\n      #ols-sf4-seesaw-card .ols-controls {\n        padding: 14px;\n      }\n\n      #ols-sf4-seesaw-card .ols-btn {\n        width: 100%;\n      }\n\n      #ols-sf4-seesaw-card .ols-viewer-badge {\n        left: 12px;\n        right: 12px;\n        text-align: center;\n      }\n    }\n  <\/style>\n\n  <div class=\"ols-model-card\">\n    <div class=\"ols-model-header\">\n      <div class=\"ols-pill\">3D molecule shape model<\/div>\n      <h2 class=\"ols-model-title\">Seesaw Shape of SF<sub>4<\/sub><\/h2>\n      <p class=\"ols-model-subtitle\">\n        In sulfur tetrafluoride, sulfur has four S-F bonding pairs and one lone pair. The five electron regions arrange themselves as a trigonal bipyramidal electron-pair arrangement. The lone pair occupies an equatorial position, leaving two axial bonds and two equatorial bonds to form a seesaw-shaped molecule.\n      <\/p>\n    <\/div>\n\n    <div class=\"ols-viewer-wrap\">\n      <div id=\"olsSF4Viewer\"><\/div>\n      <div class=\"ols-viewer-badge\">Drag to rotate \u2022 Scroll to zoom \u2022 Red cloud shows the equatorial lone pair<\/div>\n      <div class=\"ols-angle-badge\" id=\"olsSF4AngleBadge\">Bond angles: \u224887\u00b0, \u2248102\u00b0, \u2248173\u00b0<\/div>\n    <\/div>\n\n    <div class=\"ols-controls\">\n      <button type=\"button\" class=\"ols-btn is-active\" id=\"olsSF4RotateBtn\">Pause rotation<\/button>\n      <button type=\"button\" class=\"ols-btn\" id=\"olsSF4ResetBtn\">Reset view<\/button>\n    <\/div>\n\n    <div class=\"ols-explanation\">\n      <p class=\"ols-key-message\">\n        <strong>Key idea:<\/strong> SF<sub>4<\/sub> has <strong>four bonding pairs<\/strong> and <strong>one lone pair<\/strong> around sulfur. The electron-pair arrangement is <strong>trigonal bipyramidal<\/strong>. The lone pair occupies an <strong>equatorial position<\/strong>, reducing repulsion compared with an axial lone pair. The remaining four bonds form a <strong>seesaw shape<\/strong>, with approximate bond angles of <strong>87\u00b0<\/strong>, <strong>102\u00b0<\/strong> and <strong>173\u00b0<\/strong>.\n      <\/p>\n\n      <div class=\"ols-explanation-grid\">\n        <div class=\"ols-info-box\">\n          <strong>Central atom<\/strong>\n          <span>Sulfur is the central atom and sits at the centre of the model.<\/span>\n        <\/div>\n\n        <div class=\"ols-info-box\">\n          <strong>Lone pair<\/strong>\n          <span>The red electron cloud represents the single lone pair in an equatorial position.<\/span>\n        <\/div>\n\n        <div class=\"ols-info-box\">\n          <strong>Shape outcome<\/strong>\n          <span>Two axial bonds, two equatorial bonds and one equatorial lone pair produce a seesaw molecular shape.<\/span>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/div>\n\n  <script src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/JS\/seesaw.js\"><\/script>\n<\/section>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">3<\/div>\n          <h2>Electron-Pair Arrangement vs Molecular Shape<\/h2>\n        <\/div>\n        <p>The electron-pair arrangement in SF<sub>4<\/sub> is based on a <strong>trigonal bipyramidal arrangement<\/strong> because there are five electron regions around sulfur.<\/p>\n        <p>The molecular shape is different. Lone pairs are not counted as atoms when naming the shape, so the visible arrangement of the four fluorine atoms is <strong>SeeSaw-shaped<\/strong>.<\/p>\n        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>Five electron regions<\/h3>\n            <p>Four bonding pairs and one lone pair arrange themselves as far apart as possible around sulfur.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Equatorial lone pair<\/h3>\n            <p>The lone pair occupies an equatorial position in the trigonal bipyramidal arrangement. This reduces the number of close 90&deg; lone-pair interactions.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>SeeSaw bonded atoms<\/h3>\n            <p>The remaining four bonding pairs form two axial bonds and two equatorial bonds, producing a SeeSaw shape.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n\n      <article class=\"ols-note-card\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">4<\/div>\n          <h2>SeeSaw Shape Examples<\/h2>\n        <\/div>\n        <p>The SeeSaw shape is found when the central atom has four bonding pairs and one lone pair. The common exam examples include sulfur, selenium, tellurium and iodine or chlorine species with five electron regions around the central atom.<\/p>\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<\/th>\n                <th>Shape<\/th>\n                <th>Typical exam angles<\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Species\">SF<sub>4<\/sub><\/td>\n                <td data-label=\"Central atom\">S<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">SeeSaw<\/td>\n                <td data-label=\"Typical exam angles\">119&deg; and 89&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">SeF<sub>4<\/sub><\/td>\n                <td data-label=\"Central atom\">Se<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">SeeSaw<\/td>\n                <td data-label=\"Typical exam angles\">119&deg; and 89&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">TeF<sub>4<\/sub><\/td>\n                <td data-label=\"Central atom\">Te<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">SeeSaw<\/td>\n                <td data-label=\"Typical exam angles\">119&deg; and 89&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">IF<sub>4<\/sub><sup>+<\/sup><\/td>\n                <td data-label=\"Central atom\">I<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">SeeSaw<\/td>\n                <td data-label=\"Typical exam angles\">119&deg; and 89&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">ClF<sub>4<\/sub><sup>+<\/sup><\/td>\n                <td data-label=\"Central atom\">Cl<\/td>\n                <td data-label=\"Electron regions\">4 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">SeeSaw<\/td>\n                <td data-label=\"Typical exam angles\">119&deg; and 89&deg;<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <\/article>\n\n      <article class=\"ols-note-card orange\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">5<\/div>\n          <h2>How to Explain SeeSaw Shape in an Exam<\/h2>\n        <\/div>\n        <p>A full exam explanation should connect the number of electron regions to electron-pair repulsion, then explain why the lone pair is equatorial and why the bonded atoms form a SeeSaw shape.<\/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 SF<sub>4<\/sub>, the central atom is sulfur.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>2. Count bonding pairs and lone pairs<\/h3>\n            <p>Sulfur has four bonding pairs and one lone pair around it.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>3. Apply electron-pair repulsion<\/h3>\n            <p>The five electron regions arrange themselves as far apart as possible. The lone pair occupies an equatorial position to reduce repulsion.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>4. State the shape and angles<\/h3>\n            <p>The four bonded atoms form a SeeSaw shape. In simplified A Level exam tables, the bond angles are close to 119&deg; and 89&deg;. For SF<sub>4<\/sub>, the equatorial F-S-F angle is commonly described in more detailed chemistry as close to 102&deg;, with axial-equatorial angles close to 87&deg; and the axial-axial angle close to 173&deg;.<\/p>\n          <\/div>\n        <\/div>\n\n        <div class=\"ols-definition-box\">\n          <p><strong>Exam answer model:<\/strong> SF<sub>4<\/sub> has four bonding pairs and one lone pair around the central sulfur atom. The five electron regions arrange themselves as a trigonal bipyramidal electron-pair arrangement. The lone pair occupies an equatorial position to minimise repulsion. Therefore, SF<sub>4<\/sub> is SeeSaw-shaped, with bond angles close to 119&deg; and 89&deg; in the simplified exam table.<\/p>\n        <\/div>\n      <\/article>\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        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>Do not call SF<sub>4<\/sub> trigonal bipyramidal<\/h3>\n            <p>The electron-pair arrangement is trigonal bipyramidal, but the molecular shape is SeeSaw because the lone pair is not counted as an atom.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>State the lone pair is equatorial<\/h3>\n            <p>The lone pair occupies an equatorial position. This reduces repulsion compared with placing the lone pair in an axial position.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Use the correct angle detail for the context<\/h3>\n            <p>For simple exam-table recall, use approximately 119&deg; and 89&deg;. For detailed SF<sub>4<\/sub> geometry, the bp-bp angles include about 87&deg;, about 102&deg; and close to 173&deg;.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Count around the central atom only<\/h3>\n            <p>The shape is determined by the bonding pairs and lone pairs around the central atom, not by the total number of atoms in the species.<\/p>\n          <\/div>\n        <\/div>\n      <\/article>\n\n      <section class=\"ols-h5p-card\">\n        <h2>Check Your Understanding<\/h2>\n        <p>Use these short activities to check the SeeSaw shape, SF<sub>4<\/sub>, four bonding pairs, one lone pair and the approximate bond angles.<\/p>\n        <div class=\"ols-h5p-grid\">\n          <div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-216\" class=\"h5p-iframe\" data-content-id=\"216\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"seesaw.1 Drag: SeeSaw Molecular Shape Key Concepts\"><\/iframe><\/div><\/div>\n          <div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-217\" class=\"h5p-iframe\" data-content-id=\"217\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"seesaw.2 MCQ: Electron Pairs in SF4\"><\/iframe><\/div><\/div>\n          <div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-218\" class=\"h5p-iframe\" data-content-id=\"218\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"seesaw.3 MCQ: Bond Angles in SF4\"><\/iframe><\/div><\/div>\n          <div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-219\" class=\"h5p-iframe\" data-content-id=\"219\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"seesaw.4 MCQ: Exam Explanation for SF4\"><\/iframe><\/div><\/div>\n        <\/div>\n      <\/section>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">\u2713<\/div>\n          <h2>QuickSnap<\/h2>\n        <\/div>\n        <p>The SeeSaw shape is produced when a central atom has <strong>four bonding pairs<\/strong> and <strong>one lone pair<\/strong>. The lone pair occupies an equatorial position in a trigonal bipyramidal electron-pair arrangement, leaving four bonded atoms in a SeeSaw arrangement with simplified exam-table bond angles close to <strong>119&deg;<\/strong> and <strong>89&deg;<\/strong>.<\/p>\n        <div class=\"ols-key-box\"><p><strong>Memory line:<\/strong> 4 bonding pairs + 1 lone pair = SeeSaw = about 119&deg; and 89&deg;.<\/p><\/div>\n      <\/article>\n\n<section class=\"ols-course-cta-covalent-shapes\" id=\"olsCourseCtaCovalentShapes001\">\r\n  <style>\r\n    .ols-course-cta-covalent-shapes,\r\n    .ols-course-cta-covalent-shapes * {\r\n      box-sizing: border-box;\r\n    }\r\n\r\n    .ols-course-cta-covalent-shapes {\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: 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line-height: 1.5;\r\n      font-weight: 500;\r\n    }\r\n\r\n    .ols-course-cta-covalent-shapes .ols-course-cta-bottom {\r\n      display: flex;\r\n      justify-content: center;\r\n      padding-top: 22px;\r\n      border-top: 1px solid var(--border);\r\n    }\r\n\r\n    .ols-course-cta-covalent-shapes .ols-course-button {\r\n      display: inline-flex;\r\n      align-items: center;\r\n      justify-content: center;\r\n      padding: 15px 28px;\r\n      border-radius: 999px;\r\n      background: var(--navy);\r\n      color: #ffffff;\r\n      text-decoration: none;\r\n      font-size: 16px;\r\n      line-height: 1.2;\r\n      font-weight: 800;\r\n      box-shadow: 0 12px 26px rgba(28, 36, 75, 0.18);\r\n      transition:\r\n        transform 0.2s ease,\r\n        background 0.2s ease,\r\n        box-shadow 0.2s ease;\r\n    }\r\n\r\n    .ols-course-cta-covalent-shapes .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-shapes .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-shapes .ols-course-cta-top {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .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-shapes .ols-course-cta-intro-stats {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .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-shapes {\r\n        margin: 26px 0 22px;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-course-cta-card {\r\n        padding: 20px;\r\n        border-radius: 24px;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-course-cta-header-row {\r\n        align-items: stretch;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-course-button-top {\r\n        width: 100%;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-course-cta-stats,\r\n      .ols-course-cta-covalent-shapes .ols-course-cta-features {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-course-animation-wrap {\r\n        padding: 0;\r\n        border-radius: 0;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-animation-frame-shell {\r\n        height: 420px;\r\n        border-radius: 18px;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .ols-animation-play-circle {\r\n        width: 76px;\r\n        height: 76px;\r\n      }\r\n\r\n      .ols-course-cta-covalent-shapes .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-shapes .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-shapes .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-shapes-of-molecules-edexcel-t2ab\/\" aria-label=\"Open the Edexcel A Level Chemistry Topic 2A\/B Covalent Bonding, Structure 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\/05\/T2AB-Covalent-Bonding-Structure-Shapes-of-Molecules.jpg\"\r\n            alt=\"Edexcel A Level Chemistry Topic 2A\/B Covalent Bonding, Structure and Shapes of Molecules 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            Complete Topic 2A\/B Covalent Bonding, Structure & Shapes of Molecules 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-shapes-of-molecules-edexcel-t2ab\/\">\r\n            View Course\r\n          <\/a>\r\n\r\n        <\/div>\r\n\r\n        <h2>\r\n          Master Covalent Bonding, Structure and Shapes of Molecules for Edexcel A Level Chemistry\r\n        <\/h2>\r\n\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-intro-stats\">\r\n\r\n      <p class=\"ols-course-cta-intro\">\r\n        Continue from these free revision notes into the full Topic 2A\/B Covalent Bonding, Structure and Shapes of Molecules course, with guided video teaching, diagnostic MCQ practice, teacher-marked short-answer questions and a specification assignment with a personalised progress report.\r\n      <\/p>\r\n\r\n      <div class=\"ols-course-cta-stats\">\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Guided learning<\/span>\r\n          <strong>13 hours<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Video lessons<\/span>\r\n          <strong>281 mins<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>MCQ practice<\/span>\r\n          <strong>37 marks<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>SAQ practice<\/span>\r\n          <strong>169 marks<\/strong>\r\n        <\/div>\r\n\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-features\">\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Guided video teaching<\/h3>\r\n        <p>\r\n          Learn covalent bonding, dot-and-cross diagrams, giant covalent structures, electronegativity, polarity and molecular shapes 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 covalent bonding, giant covalent structures, polarity, VSEPR theory and molecular shapes 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-shapes-of-molecules-edexcel-t2ab\/\">\r\n        View Covalent Bonding & Shapes of Molecules Topic 2A\/B Course\r\n      <\/a>\r\n\r\n    <\/div>\r\n\r\n  <\/div>\r\n\r\n  <template id=\"olsCourseAnimationTemplate001\">\r\n<!DOCTYPE html>\r\n<html lang=\"en\">\r\n<head>\r\n<meta charset=\"UTF-8\">\r\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\r\n<title>OLS Combined Promo Animation<\/title>\r\n\r\n<style>\r\n*{box-sizing:border-box;}\r\n\r\nhtml.ols-animation-paused *,\r\nhtml.ols-animation-paused *::before,\r\nhtml.ols-animation-paused *::after{\r\n  animation-play-state:paused!important;\r\n}\r\n\r\n:root{\r\n  --ols-video-screen-w:1180;\r\n  --ols-video-screen-h:664;\r\n  --ols-video-screen-scale:1;\r\n  --ols-mcq-screen-w:1360;\r\n  --ols-mcq-screen-h:1130;\r\n  --ols-mcq-screen-scale:1;\r\n  --ols-saq-screen-w:1360;\r\n  --ols-saq-screen-h:965;\r\n  --ols-saq-screen-scale:1;\r\n}\r\n\r\nhtml,\r\nbody{\r\n  width:100%;\r\n  height:100%;\r\n}\r\n\r\nbody{\r\n  margin:0;\r\n  overflow:hidden;\r\n  font-family:Poppins,Arial,sans-serif;\r\n  background:#e9efff;\r\n}\r\n\r\n.ols-combined-stage{\r\n  position:relative;\r\n  width:100vw;\r\n  height:100vh;\r\n  overflow:hidden;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n}\r\n\r\n.ols-scene{\r\n  position:absolute;\r\n  inset:0;\r\n  width:100vw;\r\n  height:100vh;\r\n  opacity:0;\r\n  visibility:hidden;\r\n  pointer-events:none;\r\n}\r\n\r\n.ols-scene.active{\r\n  opacity:1;\r\n  visibility:visible;\r\n  pointer-events:auto;\r\n}\r\n\r\n.ols-scene.fade-out{\r\n  animation:olsSceneFadeOut 0.85s ease forwards;\r\n}\r\n\r\n@keyframes olsSceneFadeOut{\r\n  to{\r\n    opacity:0;\r\n    visibility:hidden;\r\n  }\r\n}\r\n\r\n.ols-title-cursor{\r\n  display:inline-block;\r\n  width:5px;\r\n  height:0.85em;\r\n  background:#1C244B;\r\n  margin-left:8px;\r\n  transform:translateY(8px);\r\n  animation:olsBlink 0.8s infinite;\r\n}\r\n\r\n.cursor{\r\n  display:inline-block;\r\n  width:3px;\r\n  height:28px;\r\n  background:#1c244b;\r\n  margin-left:3px;\r\n  transform:translateY(5px);\r\n  animation:olsBlink 0.8s infinite;\r\n}\r\n\r\n@keyframes olsBlink{\r\n  0%,45%{opacity:1;}\r\n  46%,100%{opacity:0;}\r\n}\r\n\r\n.ols-video-stage,\r\n.ols-mcq-stage,\r\n.ols-saq-stage{\r\n  width:100vw;\r\n  height:100vh;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  padding:0;\r\n  overflow:hidden;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n}\r\n\r\n.ols-video-title-screen,\r\n.ols-mcq-intro-screen,\r\n.ols-saq-intro{\r\n  position:absolute;\r\n  inset:0;\r\n  z-index:50;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n  opacity:1;\r\n  visibility:visible;\r\n  pointer-events:none;\r\n}\r\n\r\n.ols-video-title-screen.hide{animation:olsVideoTitleFadeOut 0.85s ease forwards;}\r\n.ols-mcq-intro-screen.hide{animation:olsMcqIntroFadeOut 0.85s ease forwards;}\r\n.ols-saq-intro.hide{animation:olsSaqIntroFadeOut 0.85s ease forwards;}\r\n\r\n@keyframes olsVideoTitleFadeOut{to{opacity:0;visibility:hidden;}}\r\n@keyframes olsMcqIntroFadeOut{to{opacity:0;visibility:hidden;}}\r\n@keyframes olsSaqIntroFadeOut{to{opacity:0;visibility:hidden;}}\r\n\r\n.ols-video-title-wrap,\r\n.ols-mcq-intro-title-wrap,\r\n.ols-saq-intro-title-wrap{\r\n  max-width:1250px;\r\n  padding:0 34px;\r\n  text-align:center;\r\n}\r\n\r\n.ols-video-title,\r\n.ols-mcq-intro-title,\r\n.ols-saq-intro-title{\r\n  margin:0;\r\n  font-family:Poppins,Arial,sans-serif;\r\n  font-size:clamp(52px,8vw,124px);\r\n  font-weight:600;\r\n  line-height:1.08;\r\n  color:#1C244B;\r\n  text-shadow:-9px 0 9px rgba(28,36,75,0.16);\r\n  letter-spacing:-0.045em;\r\n}\r\n\r\n#videoTitleText,\r\n#mcqIntroTitleText,\r\n#saqIntroTitleText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.ols-video-scene{\r\n  width:100%;\r\n  height:100%;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  opacity:0;\r\n  visibility:hidden;\r\n}\r\n\r\n.ols-video-scene.show{\r\n  visibility:visible;\r\n  animation:olsVideoSceneIn 1s ease forwards;\r\n}\r\n\r\n@keyframes olsVideoSceneIn{to{opacity:1;}}\r\n\r\n.ols-video-scale-wrap{\r\n  width:calc(var(--ols-video-screen-w) * 1px);\r\n  height:calc(var(--ols-video-screen-h) * 1px);\r\n  transform:scale(var(--ols-video-screen-scale));\r\n  transform-origin:center center;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n}\r\n\r\n.ols-video-card{\r\n  width:1180px;\r\n  height:664px;\r\n  border-radius:28px;\r\n  overflow:hidden;\r\n  background:#1C244B;\r\n  box-shadow:0 28px 80px rgba(28,36,75,0.28);\r\n  transform:translateY(24px) scale(0.96);\r\n  opacity:0;\r\n}\r\n\r\n.ols-video-scene.show .ols-video-card{\r\n  animation:olsVideoCardIn 1s cubic-bezier(.18,.89,.32,1.12) forwards;\r\n  animation-delay:0.2s;\r\n}\r\n\r\n@keyframes olsVideoCardIn{\r\n  to{\r\n    transform:translateY(0) scale(1);\r\n    opacity:1;\r\n  }\r\n}\r\n\r\n.ols-video-card video{\r\n  display:block;\r\n  width:100%;\r\n  height:100%;\r\n  aspect-ratio:16 \/ 9;\r\n  object-fit:cover;\r\n  border:0;\r\n}\r\n\r\n.ols-mcq-scale-wrap,\r\n.ols-saq-scale-wrap{\r\n  width:calc(var(--ols-mcq-screen-w) * 1px);\r\n  height:calc(var(--ols-mcq-screen-h) * 1px);\r\n  transform:scale(var(--ols-mcq-screen-scale));\r\n  transform-origin:center center;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:flex-start;\r\n}\r\n\r\n.ols-saq-scale-wrap{\r\n  width:calc(var(--ols-saq-screen-w) * 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<\/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\">The shapes of some species are being compared.<\/p>\r\n\r\n            <p class=\"mcq-question-main\">Which species is not tetrahedral?<\/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\">methane, CH<sub>4<\/sub><\/span>\r\n\r\n                <span id=\"mcqSpecificFeedback\" class=\"mcq-specific-feedback\">\r\n                  <span id=\"mcqCrossIcon\" class=\"mcq-cross-icon\">\u00d7<\/span>\r\n                  <span class=\"mcq-specific-feedback-text\">\r\n                    <span id=\"mcqSpecificText\"><\/span><span id=\"mcqSpecificCursor\" class=\"cursor mcq-specific-cursor\" style=\"display:none;\"><\/span>\r\n                  <\/span>\r\n                <\/span>\r\n              <\/div>\r\n\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">ammonium ion, NH<sub>4<\/sub><sup>+<\/sup><\/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\">tetrachloroiodate(III) ion, ICl<sub>4<\/sub><sup>\u2212<\/sup><\/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\">tetrachloromethane, CCl<sub>4<\/sub><\/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           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The five electron regions arrange as trigonal bipyramidal, but the lone pair occupies an equatorial position, leaving two axial S-F bonds and two equatorial S-F bonds.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>What are the bond angles in a SeeSaw molecule?<\/h3>\n            <p>In simplified A Level exam tables, the angles are often given as about 119&deg; and 89&deg;. In SF<sub>4<\/sub>, more detailed values are approximately 87&deg;, 102&deg; and 173&deg; because the equatorial lone pair compresses the bond-pair angles.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Is SeeSaw the same as trigonal bipyramidal?<\/h3>\n            <p>No. Trigonal bipyramidal is the electron-pair arrangement for five regions of negative charge. SeeSaw is the molecular shape after the single lone pair is ignored when naming the shape.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Why does the lone pair in SF<sub>4<\/sub> occupy an equatorial position?<\/h3>\n            <p>The lone pair occupies an equatorial position because this minimises repulsion. An equatorial lone pair has fewer 90&deg; interactions with bonding pairs than an axial lone pair.<\/p>\n          <\/div>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-related-card\">\n        <h2>Related Topics<\/h2>\n        <p>Use these related revision notes to strengthen the surrounding bonding and molecular shape ideas.<\/p>\n        <div class=\"ols-related-grid\">\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-bipyramidal\/\">Trigonal Bipyramidal<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/distorted-t\/\">Distorted T<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/polar-molecules\/\">Polar &amp; Non-Polar Molecules<\/a>\n        <\/div>\n      <\/section>\n\n      <article class=\"ols-attribution-card\">\n        <p><strong>Copyright notice:<\/strong> This OLS revision page was written and designed by Dr. Mohammed Al-Fatah for Online Learning System. All written explanations, page structure, visual learning design and embedded teaching content are protected by copyright. Do not copy, reproduce or redistribute this material without permission.<\/p>\n      <\/article>\n\n      <div class=\"ols-image-lightbox\" id=\"olsImageLightbox\" aria-hidden=\"true\">\n        <button class=\"ols-image-lightbox-close\" type=\"button\" aria-label=\"Close image\">&times;<\/button>\n        <img decoding=\"async\" src=\"\" alt=\"\">\n      <\/div>\n\n      <script>\n        (function(){\n          var lightbox = document.getElementById(\"olsImageLightbox\");\n          if (!lightbox) { return; }\n\n          var lightboxImage = lightbox.querySelector(\"img\");\n          var closeButton = lightbox.querySelector(\".ols-image-lightbox-close\");\n          var triggers = document.querySelectorAll(\".ols-lightbox-trigger\");\n\n          function closeLightbox() {\n            lightbox.classList.remove(\"is-open\");\n            lightbox.setAttribute(\"aria-hidden\", \"true\");\n            lightboxImage.setAttribute(\"src\", \"\");\n            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