{"id":4588,"date":"2026-05-30T06:12:51","date_gmt":"2026-05-30T05:12:51","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/"},"modified":"2026-10-25T12:14:57","modified_gmt":"2026-10-25T12:14:57","slug":"trigonal-pyramidal","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/","title":{"rendered":"Trigonal Pyramidal"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-trigonal-pyramidal-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: 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.ols-attribution-card * { box-sizing: border-box; }\n    .ols-attribution-card p { margin: 0; font-size: 14px; line-height: 1.65; font-weight: 300; color: #667085; }\n    .ols-attribution-card strong { font-weight: 700; color: #1C244B; }\n\n    @media (max-width: 1050px) {\n      .ols-main { max-width: none; }\n      .ols-related-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }\n    }\n\n    @media (max-width: 760px) {\n      .ols-title-card, .ols-note-card, .ols-h5p-card, .ols-related-card, .ols-faq-card, .ols-attribution-card { padding: 24px 18px; border-radius: 22px; }\n      .ols-note-title { align-items: flex-start; }\n      .ols-zoom-card { border-radius: 22px; }\n      .ols-zoom-card-image { min-height: 210px; padding: 14px; }\n      .ols-zoom-card-caption { padding: 16px; }\n      .ols-table-wrap { border: none; background: transparent; }\n      .ols-table, .ols-table thead, .ols-table tbody, .ols-table th, .ols-table td, .ols-table tr { display: block; width: 100%; }\n      .ols-table { border-collapse: separate; 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\">\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>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/giant-covalent-structures\/\">Giant Covalent Structures<\/a>\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>\n        <ul class=\"ols-subtopic-list\">\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-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\/edexcel\/topic-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\/edexcel\/topic-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\/edexcel\/topic-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\/edexcel\/topic-2-bonding-and-structure\/intermolecular-forces\/boiling-temperature-trends\/\">Boiling Temperature Trends<\/a>\n          <\/li>\n          <li>\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/intermolecular-forces\/choosing-solvents\/\">Choosing Solvents<\/a>\n          <\/li>\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\/structure-types\/\">Structure Types<\/a>\r\n      <\/li>\r\n\r\n    <\/ul>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Next Topics<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-3-redox-i\/\">Redox I<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\">Inorganic Chemistry &amp; The Periodic Table<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/\">Formulae, Equations &amp; Amounts<\/a>\r\n      <\/li>\r\n    <\/ul>\r\n  <\/div>\r\n<\/aside>\r\n\r\n<script>\r\n(function() {\r\n  function normalisePath(path) {\r\n    return String(path || '')\r\n      .split('?')[0]\r\n      .split('#')[0]\r\n      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href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/\">A Level Chemistry<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/\">Edexcel<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/\">Topic 2 Bonding and Structure<\/a> \/\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/\">Shapes of Molecules<\/a> \/\n        <span>Trigonal Pyramidal<\/span>\n      <\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Trigonal Pyramidal Molecular Shape<\/h1>\n        <p class=\"ols-page-intro\">A focused revision guide to the trigonal pyramidal molecular shape, using NH<sub>3<\/sub> as the key example. This page explains why three bonding pairs and one lone pair around a central atom give a three-dimensional pyramidal arrangement with bond angles of about 107&deg;.<\/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      <\/header>\n<!-- 3D card: nh3-trigonal-pyramidal (swapped 26 Sep 2026) -->\n<!-- Copyright (c) 2026 Dr. Mohammed Al-Fatah, onlinelearningsystem.net. All rights reserved. -->\n<!-- 3D card: nh3-trigonal-pyramidal (rebuilt Oct 2026) -->\n<!-- Copyright (c) 2026 Dr. Mohammed Al-Fatah, onlinelearningsystem.net. 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border:1px solid rgba(28,36,75,0.18);\n}\n.ols-npyr-001 .npyr-key i.k-ball{border-radius:50%;}\n\n@media (max-width:760px){\n  .ols-npyr-001{padding:26px; border-radius:22px;}\n  .ols-npyr-001 h2.npyr-title{font-size:20.5px;}\n  .ols-npyr-001 p.npyr-sub{font-size:13.5px;}\n  .ols-npyr-001 .npyr-stage{height:400px;}\n  .ols-npyr-001 .npyr-rowlab{min-width:100%;}\n  .ols-npyr-001 .npyr-seg button{padding:9px 13px; font-size:13px;}\n  .ols-npyr-001 .npyr-lab{font-size:10.5px; padding:4px 8px;}\n  .ols-npyr-001 .npyr-lab.l-part{font-size:9.5px; padding:3px 7px;}\n  .ols-npyr-001 .npyr-lab.l-read{font-size:12px; padding:5px 9px;}\n  .ols-npyr-001 .npyr-caption{font-size:10.5px; padding:5px 9px; max-width:64%;}\n  .ols-npyr-001 .npyr-badge{font-size:10.5px; padding:4px 9px;}\n  .ols-npyr-001 .npyr-badge.b-eq{font-size:11px;}\n  .ols-npyr-001 .npyr-badges{max-width:calc(100% - 28px);}\n  .ols-npyr-001 .npyr-info{padding:18px;}\n}\n\/* on a phone the caption needs the full top row, so the drag hint goes *\/\n@media (max-width:480px){\n  .ols-npyr-001 .npyr-hint{display:none;}\n  .ols-npyr-001 .npyr-caption{max-width:calc(100% - 28px);}\n}\n@media (prefers-reduced-motion:reduce){\n  .ols-npyr-001 .npyr-seg button,.ols-npyr-001 .npyr-pill{transition:none;}\n}\n\n.ols-cc-npyr-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-npyr-001 a{color:#aab0c0; text-decoration:none;}\n.ols-cc-npyr-001 a:hover{text-decoration:underline;}\n.ols-npyr-001 .npyr-seg button{display:inline-flex; align-items:center;}\n.ols-npyr-001 .npyr-seg button .npyr-n{display:inline-flex; align-items:center; justify-content:center; width:20px; height:20px; margin-right:9px; border-radius:50%; font-size:11px; font-weight:600; background:rgba(37,99,235,0.10); color:#2563eb; flex:0 0 auto;}\n.ols-npyr-001 .npyr-seg button[aria-pressed=\"true\"] .npyr-n{background:#ffffff; color:#2563eb;}\n<\/style>\n\n<div class=\"npyr-head\">\n  <h2 class=\"npyr-title\">Trigonal Pyramidal Shape of NH\u2083<\/h2>\n  <p class=\"npyr-sub\">Choose a step to watch four electron pairs form a tetrahedron, one stay as a lone pair and squeeze the bond angles to 107\u00b0.<\/p>\n<\/div>\n\n<div class=\"npyr-stage\" id=\"npyrStage\">\n  <canvas class=\"npyr-canvas\" id=\"npyrCanvas\"><\/canvas>\n  <div class=\"npyr-overlay\" id=\"npyrOverlay\"><\/div>\n  <div class=\"npyr-caption\" id=\"npyrCaption\"><\/div>\n  <div class=\"npyr-hint\" id=\"npyrHint\">Drag to rotate<\/div>\n  <div class=\"npyr-badges\" id=\"npyrBadges\"><\/div>\n<\/div>\n\n<div class=\"npyr-controls\">\n  <div class=\"npyr-row\">\n    <span class=\"npyr-rowlab\">Step<\/span>\n    <div class=\"npyr-seg\" role=\"group\" aria-label=\"Step\">\n      <button type=\"button\" data-step=\"1\" aria-pressed=\"true\"><span class=\"npyr-n\">1<\/span>Four electron pairs<\/button>\n      <button type=\"button\" data-step=\"2\" aria-pressed=\"false\"><span class=\"npyr-n\">2<\/span>One lone pair<\/button>\n      <button type=\"button\" data-step=\"3\" aria-pressed=\"false\"><span class=\"npyr-n\">3<\/span>Squeezed to 107\u00b0<\/button>\n      <button type=\"button\" data-step=\"4\" aria-pressed=\"false\"><span class=\"npyr-n\">4<\/span>Name the shape<\/button>\n    <\/div>\n  <\/div>\n\n  <div class=\"npyr-row\">\n    <span class=\"npyr-rowlab\">View<\/span>\n    <button type=\"button\" class=\"npyr-pill\" id=\"npyrResetV\">Reset view<\/button>\n  <\/div>\n<\/div>\n\n<div class=\"npyr-info\">\n  <h3 id=\"npyrInfoTitle\"><\/h3>\n  <p id=\"npyrInfoText\"><\/p>\n  <div class=\"npyr-facts\" id=\"npyrFacts\"><\/div>\n  <div class=\"npyr-key\">\n    <span><i class=\"k-ball\" style=\"background:#3060d0\"><\/i>Nitrogen<\/span>\n    <span><i class=\"k-ball\" style=\"background:#ececf0\"><\/i>Hydrogen<\/span>\n    <span><i class=\"\" style=\"background:rgba(70,128,220,0.45)\"><\/i>Electron pair (bonding)<\/span>\n    <span><i class=\"\" style=\"background:rgba(128,92,214,0.5)\"><\/i>Lone pair<\/span>\n    <span><i class=\"k-ball\" style=\"background:#fac828\"><\/i>Electron<\/span>\n    <span><i class=\"\" style=\"background:#c9961c\"><\/i>Bond angle<\/span>\n  <\/div>\n<\/div>\n\n<script src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/JS\/nh3-trigonal-pyramidal.js?v=20261025p\"><\/script>\n<\/section>\n\n<p class=\"ols-cc-npyr-001\">&copy; Dr. Mohammed Al-Fatah &#8211; <a href=\"https:\/\/www.onlinelearningsystem.net\" target=\"_blank\" rel=\"noopener\">onlinelearningsystem.net<\/a><\/p>\n\n\n<style>\n  .ols-trigonal-pyramidal-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-trigonal-pyramidal-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-trigonal-pyramidal-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-trigonal-pyramidal-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-trigonal-pyramidal-molecular-shape-9ch0-page .ols-h5p-grid {\n    display: grid;\n    gap: 18px;\n    margin-top: 22px;\n  }\n  .ols-trigonal-pyramidal-molecular-shape-9ch0-page .ols-h5p-frame {\n    margin-top: 0;\n  }\n  .ols-trigonal-pyramidal-molecular-shape-9ch0-page .ols-formula {\n    white-space: nowrap;\n  }\n  @media (max-width: 760px) {\n    .ols-trigonal-pyramidal-molecular-shape-9ch0-page .ols-spec-grid {\n      grid-template-columns: 1fr;\n    }\n  }\n<\/style>\n\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: Forces Between Charges<\/h2>\n<p>Before you start, check the GCSE ideas about forces between charges that this page builds on.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-content\" data-content-id=\"679\"><\/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 Trigonal Pyramidal Means<\/h2>\n        <\/div>\n        <p>A <strong>trigonal pyramidal<\/strong> molecule has three atoms bonded to a central atom, with one lone pair also present on the central atom. The three bonded atoms form a triangular base, while the central atom sits above the base to give a pyramidal shape.<\/p>\n        <p>The key example for this page is <strong>NH<sub>3<\/sub><\/strong>. Nitrogen is the central atom, each hydrogen atom is bonded to nitrogen, and nitrogen 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>3 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 angle<\/strong>\n            <span>about 107&deg; between the bonds<\/span>\n          <\/div>\n        <\/div>\n\n        <div class=\"ols-key-box\"><p><strong>Key idea:<\/strong> three bonding pairs and one lone pair around a central atom give a trigonal pyramidal shape with bond angles of about 107&deg;.<\/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 NH<sub>3<\/sub> Is Trigonal Pyramidal<\/h2>\n        <\/div>\n        <p>In NH<sub>3<\/sub>, the central nitrogen atom is surrounded by three N-H bonding pairs and one lone pair. These four regions of negative charge repel one another and are based on a tetrahedral electron-pair arrangement.<\/p>\n        <p>The <strong>molecular shape<\/strong> only considers the positions of the atoms, not the invisible lone pair. Therefore, NH<sub>3<\/sub> is described as <strong>trigonal pyramidal<\/strong>, not tetrahedral.<\/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\/10\/t3-cd-12-nh3-pyramidal.svg\" alt=\"Trigonal pyramidal NH\u2083 with a lone pair and 107\u00b0 angle, its dot-and-cross diagram, and H\u2083O\u207a drawn the same way\" class=\"ols-zoomable-img ols-lightbox-target\" draggable=\"false\" width=\"1516\" height=\"948\">\n          <\/div>\n          <div class=\"ols-zoom-card-caption\">\n            <p>A trigonal pyramidal species has three bonding regions and one lone pair around the central atom, giving a bond angle of about 107&deg;.<\/p>\n          <\/div>\n        <\/div>\n      <div class=\"ols-zoom-card\">\n<div class=\"ols-zoom-card-image\">\n<a class=\"ols-lightbox-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t3-img-26-countnh3.jpg\" aria-label=\"Open image full screen\">\n<img decoding=\"async\" class=\"ols-zoomable-img ols-lightbox-target\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t3-img-26-countnh3.jpg\" alt=\"Five-step electron-pair count for NH\u2083 giving three bonding pairs, one lone pair and a trigonal pyramidal 107\u00b0 shape\">\n<\/a>\n<\/div>\n<div class=\"ols-zoom-card-caption\"><p>Nitrogen keeps 2 of its 5 outer electrons as a lone pair: three bonding regions and one lone pair give a trigonal pyramid.<\/p><\/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: Arrangement or Shape?<\/h2>\n<p>Choose the line that gives the arrangement and the shape of SbCl\u2083.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-189\" class=\"h5p-iframe\" data-content-id=\"189\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Trigonal Pyramidal MCQ: Arrangement and Shape of Antimony Trichloride\"><\/iframe><\/div><\/div>\n<\/section>\n\n\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 electron-pair arrangement around nitrogen in NH<sub>3<\/sub> is based on four electron domains: three bonding pairs and one lone pair. A lone pair occupies more space around the central atom than a bonding pair because it is attracted to only one nucleus.<\/p>\n        <p>This means the lone pair repels the N-H bonding pairs more strongly than the bonding pairs repel each other. The H-N-H bond angle is compressed from the tetrahedral value of 109.5&deg; to about <strong>107&deg;<\/strong>.<\/p>\n\n        <div class=\"ols-table-wrap\">\n          <table class=\"ols-table\">\n            <thead>\n              <tr>\n                <th>Feature<\/th>\n                <th>Trigonal pyramidal value<\/th>\n                <th>Meaning in NH<sub>3<\/sub><\/th>\n              <\/tr>\n            <\/thead>\n            <tbody>\n              <tr>\n                <td data-label=\"Feature\">Number of bonding pairs<\/td>\n                <td data-label=\"Trigonal pyramidal value\">3<\/td>\n                <td data-label=\"Meaning in NH3\">Three N-H bonding pairs form the visible triangular base of the pyramid.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Feature\">Number of lone pairs<\/td>\n                <td data-label=\"Trigonal pyramidal value\">1<\/td>\n                <td data-label=\"Meaning in NH3\">The lone pair repels more strongly than bonding pairs and compresses the bond angle.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Feature\">Bond angle<\/td>\n                <td data-label=\"Trigonal pyramidal value\">about 107&deg;<\/td>\n                <td data-label=\"Meaning in NH3\">The angle is smaller than 109.5&deg; because of lone-pair repulsion.<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Feature\">Molecular shape<\/td>\n                <td data-label=\"Trigonal pyramidal value\">Trigonal pyramidal<\/td>\n                <td data-label=\"Meaning in NH3\">Only the positions of the bonded atoms are used to name the molecular shape.<\/td>\n              <\/tr>\n            <\/tbody>\n          <\/table>\n        <\/div>\n      <div class=\"ols-zoom-card\">\n<div class=\"ols-zoom-card-image\">\n<a class=\"ols-lightbox-link\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t3-img-20-fourpairs.jpg\" aria-label=\"Open image full screen\">\n<img decoding=\"async\" class=\"ols-zoomable-img ols-lightbox-target\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/10\/t3-img-20-fourpairs.jpg\" alt=\"CH\u2084, NH\u2083 and H\u2082O ball sketches with angles 109.5\u00b0, 107\u00b0 and 104.5\u00b0, and the order of electron-pair repulsion\">\n<\/a>\n<\/div>\n<div class=\"ols-zoom-card-caption\"><p>Swapping a bonding pair for a lone pair closes the angle by about 2.5\u00b0 each time: 109.5\u00b0, 107\u00b0, 104.5\u00b0.<\/p><\/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: Predict a New Ion<\/h2>\n<p>Drag the words into place to predict the shape of the methyl anion.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-188\" class=\"h5p-iframe\" data-content-id=\"188\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Trigonal Pyramidal Drag: Shape and Bond Angle of the Methyl Anion\"><\/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 Trigonal Pyramidal Species<\/h2>\n        <\/div>\n        <p>Several molecules and ions use the same three-bonding-pair and one-lone-pair arrangement around the central atom. Other examples are <strong>NCl<sub>3<\/sub><\/strong>, <strong>PF<sub>3<\/sub><\/strong>, <strong>ClO<sub>3<\/sub><sup>&#8211;<\/sup><\/strong> and <strong>H<sub>3<\/sub>O<sup>+<\/sup><\/strong>.<\/p>\n        <p>For exam purposes, focus on the central atom, count the bonding pairs and lone pairs around it, then state the shape and approximate 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\">NH<sub>3<\/sub><\/td>\n                <td data-label=\"Central atom\">N<\/td>\n                <td data-label=\"Electron regions\">3 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">Trigonal pyramidal<\/td>\n                <td data-label=\"Bond angle\">about 107&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">NCl<sub>3<\/sub><\/td>\n                <td data-label=\"Central atom\">N<\/td>\n                <td data-label=\"Electron regions\">3 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">Trigonal pyramidal<\/td>\n                <td data-label=\"Bond angle\">about 107&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">PF<sub>3<\/sub><\/td>\n                <td data-label=\"Central atom\">P<\/td>\n                <td data-label=\"Electron regions\">3 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">Trigonal pyramidal<\/td>\n                <td data-label=\"Bond angle\">about 107&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">ClO<sub>3<\/sub><sup>&#8211;<\/sup><\/td>\n                <td data-label=\"Central atom\">Cl<\/td>\n                <td data-label=\"Electron regions\">3 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">Trigonal pyramidal<\/td>\n                <td data-label=\"Bond angle\">about 107&deg;<\/td>\n              <\/tr>\n              <tr>\n                <td data-label=\"Species\">H<sub>3<\/sub>O<sup>+<\/sup><\/td>\n                <td data-label=\"Central atom\">O<\/td>\n                <td data-label=\"Electron regions\">3 bonding regions, 1 lone pair<\/td>\n                <td data-label=\"Shape\">Trigonal pyramidal<\/td>\n                <td data-label=\"Bond angle\">about 107&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: Pyramid or Not?<\/h2>\n<p>Work out each species on paper, then flip the card to check.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-190\" class=\"h5p-iframe\" data-content-id=\"190\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Trigonal Pyramidal Flip Cards: Three Bonds, but Is It a Pyramid?\"><\/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 Trigonal Pyramidal Shape in an Exam<\/h2>\n        <\/div>\n        <p>A full exam explanation should connect the number of electron pairs to electron-pair repulsion, then explain why the bond angle is slightly smaller than the tetrahedral 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 NH<sub>3<\/sub>, the central atom is nitrogen.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>2. Count bonding pairs and lone pairs<\/h3>\n            <p>Nitrogen has three 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 electron pairs repel and arrange themselves as far apart as possible, but the lone pair repels more strongly than a bonding pair.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>4. State the shape and angle<\/h3>\n            <p>The molecule is trigonal pyramidal with bond angles of about 107&deg;.<\/p>\n          <\/div>\n        <\/div>\n\n        <div class=\"ols-definition-box\">\n          <p><strong>Exam answer model:<\/strong> NH<sub>3<\/sub> has three bonding pairs and one lone pair around the central nitrogen atom. The electron pairs repel and arrange themselves as far apart as possible.<\/p>\n<p>The lone pair repels the bonding pairs more strongly, compressing the H-N-H bond angle from 109.5&deg; to about 107&deg;. Therefore, NH<sub>3<\/sub> is trigonal pyramidal.<\/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: Explain the Difference<\/h2>\n<p>Write a short explanation, then compare it with the mark points and the model answer.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-191\" class=\"h5p-iframe\" data-content-id=\"191\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Trigonal Pyramidal Explain: Bond Angles in PCl\u2083 and PCl\u2084\u207a\"><\/iframe><\/div><\/div>\n<\/section>\n<section class=\"ols-h5p-card ols-h5p-inline\">\n<span class=\"ols-h5p-kicker\">Check your understanding<\/span>\n<h2>Quick Check: The Whole Page in Four Statements<\/h2>\n<p>In each round, pick the one accurate statement to review everything on this page.<\/p>\n<div class=\"ols-h5p-frame\"><div class=\"h5p-iframe-wrapper\"><iframe id=\"h5p-iframe-1298\" class=\"h5p-iframe\" data-content-id=\"1298\" style=\"height:1px\" src=\"about:blank\" frameBorder=\"0\" scrolling=\"no\" title=\"Trigonal Pyramidal Summary: One Lone Pair, a Pyramid and About 107\u00b0\"><\/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>Trigonal pyramidal questions often test whether you can distinguish the electron-pair arrangement from the molecular shape.<\/p>\n        <div class=\"ols-rule-list\">\n          <div class=\"ols-rule-item\">\n            <h3>Do not call NH<sub>3<\/sub> tetrahedral<\/h3>\n            <p>The electron-pair arrangement is based on a tetrahedron, but the molecular shape is trigonal pyramidal because one region is a lone pair rather than a bonded atom.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Do not write 109.5&deg;<\/h3>\n            <p>109.5&deg; is the ideal tetrahedral angle. In NH<sub>3<\/sub>, the lone pair compresses the H-N-H angle to about 107&deg;.<\/p>\n          <\/div>\n          <div class=\"ols-rule-item\">\n            <h3>Use lone-pair repulsion language<\/h3>\n            <p>Marks usually require the idea that a lone pair repels bonding pairs more strongly than bonding pairs repel each other.<\/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 bonds or lone pairs in the whole species.<\/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 trigonal pyramidal shape is produced when a central atom has <strong>three bonding pairs<\/strong> and <strong>one lone pair<\/strong>. The lone pair repels bonding pairs more strongly and compresses the bond angle to about <strong>107&deg;<\/strong>.<\/p>\n        <div class=\"ols-key-box\"><p><strong>Memory line:<\/strong> 3 bonding pairs + 1 lone pair = trigonal pyramidal = about 107&deg;.<\/p><\/div>\n      <\/article>\n\n      <section class=\"ols-faq-card\">\n        <h2>FAQs<\/h2>\n        <p>These questions target the common points students confuse when learning the trigonal pyramidal molecular shape.<\/p>\n        <div class=\"ols-faq-list\">\n          <div class=\"ols-faq-item\">\n            <h3>What makes a molecule trigonal pyramidal?<\/h3>\n            <p>A molecule is trigonal pyramidal when the central atom has three bonding pairs and one lone pair. The bonded atoms form a pyramidal shape because the lone pair occupies one electron domain but is not shown as an atom in the molecular shape.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Why is NH<sub>3<\/sub> trigonal pyramidal?<\/h3>\n            <p>NH<sub>3<\/sub> has three N-H bonding pairs and one lone pair around the central nitrogen atom. The four electron domains are based on a tetrahedral arrangement, but the visible molecular shape is trigonal pyramidal.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>What is the bond angle in NH<sub>3<\/sub>?<\/h3>\n            <p>The H-N-H bond angle in NH<sub>3<\/sub> is about 107&deg;. It is smaller than 109.5&deg; because the lone pair repels the bonding pairs more strongly.<\/p>\n          <\/div>\n          <div class=\"ols-faq-item\">\n            <h3>Why is NH<sub>3<\/sub> not called tetrahedral?<\/h3>\n            <p>The electron-pair arrangement around nitrogen is based on a tetrahedron, but the molecular shape is named from the positions of the atoms only. Since one of the four electron domains is a lone pair, the molecular shape is trigonal pyramidal.<\/p>\n          <\/div>\n        \n<div class=\"ols-faq-item\">\n<h3>Why does a lone pair repel more strongly than a bonding pair?<\/h3>\n<p>A lone pair is held by only one nucleus, so its electron density sits closer to the central atom and spreads more widely. It pushes the bonding pairs together, which is why NH<sub>3<\/sub> is 107&deg; and not 109.5&deg;.<\/p>\n<\/div>\n<\/div>\n      <\/section>\n\n      <!-- author card (moved to the end, 10 Oct 2026) -->\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\n\n      <section class=\"ols-related-card\">\n        <h2>Related Topics<\/h2>\n        <p>Use these pages to connect trigonal pyramidal 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\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/\">Covalent Bonding<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/covalent-bonding\/electronegativity\/\">Electronegativity<\/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\/tetrahedral\/\">Tetrahedral<\/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\/bent\/\">Bent<\/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\/trigonal-planar\/\">Trigonal Planar<\/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 Molecules<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card ols-attr-std\" aria-label=\"Copyright notice\">\n<style id=\"ols-attribution-card-css\">.ols-attribution-card.ols-attr-std{background:linear-gradient(135deg,#ffffff,#f8fbff);border:1px solid rgba(28,36,75,0.14);border-radius:28px;box-shadow:0 18px 45px rgba(28,36,75,0.10);padding:34px;margin:24px 0;overflow:hidden;font-family:Poppins,Arial,sans-serif;box-sizing:border-box}.ols-attribution-card.ols-attr-std *{box-sizing:border-box}.ols-attribution-card.ols-attr-std p{margin:0;font-size:14px;line-height:1.65;font-weight:300;color:#667085}.ols-attribution-card.ols-attr-std strong{font-weight:700;color:#1C244B}@media (max-width:760px){.ols-attribution-card.ols-attr-std{padding:24px 18px;border-radius:22px}}<\/style>\n<p><strong>Copyright notice:<\/strong> This OLS revision content, including the explanations, layout, diagrams, tables and embedded learning structure, is authored for Online Learning System by Dr. Mohammed Al-Fatah. It may not be copied, reproduced, redistributed or adapted without written permission.<\/p>\n<\/section>\n\n      <script type=\"application\/ld+json\">\n{\n    \"@context\": \"https:\/\/schema.org\",\n    \"@graph\": [\n        {\n            \"@type\": \"WebPage\",\n            \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/#webpage\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-2-bonding-and-structure\/shapes-of-molecules\/trigonal-pyramidal\/\",\n            \"name\": \"Trigonal Pyramidal Molecular Shape | Edexcel A Level Chemistry\",\n            \"description\": \"Revision notes explaining trigonal pyramidal molecular shape using NH3, including three bonding pairs, one lone pair, lone-pair repulsion and the 107 degree bond angle.\",\n            \"isPartOf\": {\n                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This page explains why three bonding pairs and one lone pair around a central [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":4572,"menu_order":3,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-4588","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4588","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=4588"}],"version-history":[{"count":2,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4588\/revisions"}],"predecessor-version":[{"id":24840,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4588\/revisions\/24840"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4572"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=4588"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}