{"id":3985,"date":"2026-05-21T04:54:50","date_gmt":"2026-05-21T03:54:50","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/"},"modified":"2026-05-26T11:28:50","modified_gmt":"2026-05-26T10:28:50","slug":"topic-2-atomic-structure-and-the-periodic-table","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/","title":{"rendered":"Topic 2 Atomic Structure and The Periodic Table"},"content":{"rendered":"\n<div class=\"ols-t2-page\">\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 Atomic Structure and The Periodic Table<\/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-international\/topic-2-atomic-structure-and-the-periodic-table\/atomic-structure\/\">Atomic Structure<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/mass-spectrometry\/\">Mass Spectrometry<\/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-international\/topic-2-atomic-structure-and-the-periodic-table\/mass-spectrometry\/the-mass-spectrometer\/\">The Mass Spectrometer<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/mass-spectrometry\/ram-calculations\/\">RAM Calculations<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/mass-spectrometry\/predicting-diatomic-mass-spectra\/\">Predicting Diatomic Mass Spectra<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/mass-spectrometry\/identifying-compounds-from-mass-spectra\/\">Identifying Compounds from Mass Spectra<\/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-international\/topic-2-atomic-structure-and-the-periodic-table\/quantum-model\/\">Quantum Model<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/ionisation-energy\/\">Ionisation Energy<\/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-international\/topic-2-atomic-structure-and-the-periodic-table\/ionisation-energy\/introduction-to-ionisation-energy\/\">Introduction to Ionisation Energy<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/ionisation-energy\/successive-ionisation-energy\/\">Successive Ionisation Energy<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/ionisation-energy\/trends-in-a-period\/\">Trends in a Period<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/ionisation-energy\/trends-in-a-group\/\">Trends in a Group<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\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-international\/topic-3-bonding-structure\/\">Bonding &amp; Structure<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/\">Organic Chemistry &amp; Alkanes<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-5-alkenes\/\">Alkenes<\/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 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<nav class=\"ols-t2-breadcrumb\" 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-international\/\">Edexcel International<\/a> \/\n        <span>Topic 2 Atomic Structure and the Periodic Table<\/span>\n      <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t2-intro\">\n    <div class=\"ols-t2-container\">\n      <div class=\"ols-t2-intro-inner\">\n\n        <div>\n          <div class=\"ols-t2-eyebrow\">Edexcel International A Level Chemistry<\/div>\n          <h1>Topic 2<br>Atomic Structure<br>&amp; The Periodic Table<\/h1>\n          <div class=\"ols-t2-accent-bar\"><\/div>\n          <p class=\"ols-t2-intro-lead\">\n            Topic 2 builds the foundation for atomic structure, isotopes, mass spectrometry, the quantum model, electronic configuration, ionisation energy and periodic trends. These ideas explain how evidence from spectra and ionisation energies supports modern models of electronic structure.\n          <\/p>\n        <\/div>\n\n        <div class=\"ols-t2-info-grid\">\n          <div class=\"ols-t2-info-card\">\n            <div class=\"ols-t2-info-card-label\">Exam Unit<\/div>\n            <div class=\"ols-t2-info-card-value\">Unit 1<\/div>\n            <div class=\"ols-t2-info-card-sub\">WCH11\/01 &#8211; IAS<\/div>\n          <\/div>\n          <div class=\"ols-t2-info-card\">\n            <div class=\"ols-t2-info-card-label\">Specification Points<\/div>\n            <div class=\"ols-t2-info-card-value\">2.1 &#8211; 2.18<\/div>\n            <div class=\"ols-t2-info-card-sub\">18 points covered<\/div>\n          <\/div>\n          <div class=\"ols-t2-info-card\">\n            <div class=\"ols-t2-info-card-label\">Topic Parts<\/div>\n            <div class=\"ols-t2-info-card-value\">4 parts<\/div>\n            <div class=\"ols-t2-info-card-sub\">Revision notes available<\/div>\n          <\/div>\n          <div class=\"ols-t2-info-card\">\n            <div class=\"ols-t2-info-card-label\">Exam Board<\/div>\n            <div class=\"ols-t2-info-card-value\">Edexcel IAL<\/div>\n            <div class=\"ols-t2-info-card-sub\">Pearson International<\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-t2-topics\">\n    <div class=\"ols-t2-container\">\n\n      <div class=\"ols-t2-section-header\">\n        <h2 class=\"ols-t2-section-title\">Revision Notes<\/h2>\n      <\/div>\n\n      <div class=\"ols-t2-cards-grid\">\n\n        <!-- Card 1: Atomic Structure -->\n        <a class=\"ols-t2-card ols-t2-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/atomic-structure\/\">\n          <div class=\"ols-t2-card-img-wrap\">\n            <div class=\"ols-t2-visual ols-t2-visual--atom\">\n              <div class=\"ols-t2-visual-panel\">\n                <div class=\"ols-t2-visual-kicker\">Atoms and isotopes<\/div>\n                <div class=\"ols-t2-atom-diagram\" aria-hidden=\"true\">\n                  <span class=\"ols-t2-atom-nucleus\"><\/span>\n                  <span class=\"ols-t2-atom-electron e1\"><\/span>\n                  <span class=\"ols-t2-atom-electron e2\"><\/span>\n                <\/div>\n                <div class=\"ols-t2-visual-main\">Atomic<br>Structure<\/div>\n                <div class=\"ols-t2-visual-sub\">protons, neutrons, electrons and isotopes<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t2-card-num\">1<\/div>\n            <span class=\"ols-t2-card-status ols-t2-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t2-card-body\">\n            <p class=\"ols-t2-card-title\">Atomic Structure<\/p>\n            <p class=\"ols-t2-card-desc\">Subatomic particles, relative mass and charge, atomic number, mass number, isotopes and particle calculations.<\/p>\n            <span class=\"ols-t2-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 2: Mass Spectrometry -->\n        <a class=\"ols-t2-card ols-t2-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/mass-spectrometry\/\">\n          <div class=\"ols-t2-card-img-wrap\">\n            <div class=\"ols-t2-visual ols-t2-visual--mass-spec\">\n              <div class=\"ols-t2-visual-panel\">\n                <div class=\"ols-t2-visual-kicker\">Spectra and abundance<\/div>\n                <div class=\"ols-t2-ms-line\" aria-hidden=\"true\">\n                  <span class=\"ols-t2-ms-peak p1\"><\/span>\n                  <span class=\"ols-t2-ms-peak p2\"><\/span>\n                  <span class=\"ols-t2-ms-peak p3\"><\/span>\n                <\/div>\n                <div class=\"ols-t2-visual-main\">Mass<br>Spectrometry<\/div>\n                <div class=\"ols-t2-visual-sub\">isotopic composition, RAM, RMM and molecular ions<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t2-card-num\">2<\/div>\n            <span class=\"ols-t2-card-status ols-t2-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t2-card-body\">\n            <p class=\"ols-t2-card-title\">Mass Spectrometry<\/p>\n            <p class=\"ols-t2-card-desc\">Principles of a mass spectrometer, interpreting spectra, isotope abundance, relative atomic mass and diatomic mass spectra.<\/p>\n            <span class=\"ols-t2-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 3: Quantum Model -->\n        <a class=\"ols-t2-card ols-t2-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/quantum-model\/\">\n          <div class=\"ols-t2-card-img-wrap\">\n            <div class=\"ols-t2-visual ols-t2-visual--quantum\">\n              <div class=\"ols-t2-visual-panel\">\n                <div class=\"ols-t2-visual-kicker\">Orbitals and subshells<\/div>\n                <div class=\"ols-t2-orbital\" aria-hidden=\"true\">\n                  <span><\/span>\n                  <span><\/span>\n                <\/div>\n                <div class=\"ols-t2-visual-main\">Quantum<br>Model<\/div>\n                <div class=\"ols-t2-visual-sub\">s and p orbitals, subshells and configurations<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t2-card-num\">3<\/div>\n            <span class=\"ols-t2-card-status ols-t2-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t2-card-body\">\n            <p class=\"ols-t2-card-title\">Quantum Model<\/p>\n            <p class=\"ols-t2-card-desc\">Orbitals, quantum shells, sub-shells, orbital box notation, electronic configuration and periodic blocks.<\/p>\n            <span class=\"ols-t2-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 4: Ionisation Energy -->\n        <a class=\"ols-t2-card ols-t2-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/ionisation-energy\/\">\n          <div class=\"ols-t2-card-img-wrap\">\n            <div class=\"ols-t2-visual ols-t2-visual--ionisation\">\n              <div class=\"ols-t2-visual-panel\">\n                <div class=\"ols-t2-visual-kicker\">Energy and trends<\/div>\n                <div class=\"ols-t2-ie-arrow\" aria-hidden=\"true\"><span class=\"ols-t2-ie-dot\"><\/span><\/div>\n                <div class=\"ols-t2-visual-main\">Ionisation<br>Energy<\/div>\n                <div class=\"ols-t2-visual-sub\">successive values, shielding and periodic trends<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t2-card-num\">4<\/div>\n            <span class=\"ols-t2-card-status ols-t2-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t2-card-body\">\n            <p class=\"ols-t2-card-title\">Ionisation Energy<\/p>\n            <p class=\"ols-t2-card-desc\">First, second and third ionisation energies, successive ionisation energies, periodic trends and evidence for electronic structure.<\/p>\n            <span class=\"ols-t2-card-cta\">\n              Start revising\n              <svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg>\n            <\/span>\n          <\/div>\n        <\/a>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION -->\n  <section class=\"ols-t2-spec-section\">\n    <div class=\"ols-t2-container\">\n      <div class=\"ols-t2-spec-wrap\">\n        <div class=\"ols-t2-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-t2-spec-heading\">Topic 2 Atomic Structure and the Periodic Table &#8211; Edexcel International A Level Chemistry<\/h2>\n        <p class=\"ols-t2-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 2.<\/p>\n\n        <h3 class=\"ols-t2-spec-group-title\">Atomic Structure<\/h3>\n        <div class=\"ols-t2-spec-rows\">\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.1<\/div>\n            <div class=\"ols-t2-spec-text\">know the structure of an atom in terms of electrons, protons and neutrons<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.2<\/div>\n            <div class=\"ols-t2-spec-text\">know the relative mass and charge of protons, neutrons and electrons<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.3<\/div>\n            <div class=\"ols-t2-spec-text\">know what is meant by the terms atomic, proton, number and mass number<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.4<\/div>\n            <div class=\"ols-t2-spec-text\">be able to use the atomic number and the mass number to determine the number of each type of subatomic particle in an atom or ion<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.5<\/div>\n            <div class=\"ols-t2-spec-text\">understand the term isotope<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t2-spec-group-title\">Mass Spectrometry<\/h3>\n        <div class=\"ols-t2-spec-rows\">\n          <div class=\"ols-t2-spec-row ols-t2-spec-row--mid\">\n            <div class=\"ols-t2-spec-code\">2.6<\/div>\n            <div class=\"ols-t2-spec-text\">\n              <div style=\"margin:0 0 12px;\">understand the basic principles of a mass spectrometer and be able to analyse and interpret mass spectra to:<\/div>\n              <div class=\"ols-t2-spec-sub-list\">\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">deduce the isotopic composition of a sample of an element<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">calculate the relative atomic mass of an element from relative abundances of isotopes and vice versa<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">iii<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">determine the relative molecular mass of a molecule, and hence identify molecules in a sample<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">iv<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">understand that ions in a mass spectrometer may have a 2+ charge<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.7<\/div>\n            <div class=\"ols-t2-spec-text\">be able to predict mass spectra, including relative peak heights, for diatomic molecules, including chlorine, given the isotopic abundances<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t2-spec-group-title\">Quantum Model and Electronic Configuration<\/h3>\n        <div class=\"ols-t2-spec-rows\">\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.9<\/div>\n            <div class=\"ols-t2-spec-text\">know that an orbital is a region within an atom that can hold up to two electrons with opposite spins<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row ols-t2-spec-row--mid\">\n            <div class=\"ols-t2-spec-code\">2.11<\/div>\n            <div class=\"ols-t2-spec-text\">\n              <div style=\"margin:0 0 12px;\">know that ideas about electronic structure developed from:<\/div>\n              <div class=\"ols-t2-spec-sub-list\">\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">an understanding that successive ionisation energies provide evidence for the existence of quantum shells and the group to which the element belongs<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">an understanding that the first ionisation energy of successive elements provides evidence for electron sub-shells<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.12<\/div>\n            <div class=\"ols-t2-spec-text\">be able to describe the shapes of s and p orbitals<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row ols-t2-spec-row--mid\">\n            <div class=\"ols-t2-spec-code\">2.13<\/div>\n            <div class=\"ols-t2-spec-text\">\n              <div style=\"margin:0 0 12px;\">know that orbitals in sub-shells:<\/div>\n              <div class=\"ols-t2-spec-sub-list\">\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">each take a single electron before pairing up<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">pair up with two electrons of opposite spin<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.14<\/div>\n            <div class=\"ols-t2-spec-text\">be able to predict the electronic configuration of atoms of the elements from hydrogen to krypton inclusive and their ions, using s, p, d notation and electron-in-boxes notation<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.15<\/div>\n            <div class=\"ols-t2-spec-text\">understand that electronic configuration determines the chemical properties of an element<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.16<\/div>\n            <div class=\"ols-t2-spec-text\">know that the Periodic Table is divided into blocks, such as s, p and d, and know the number of electrons that can occupy s, p and d sub-shells in the first four quantum shells<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t2-spec-group-title\">Ionisation Energy and Periodic Trends<\/h3>\n        <div class=\"ols-t2-spec-rows\">\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.8<\/div>\n            <div class=\"ols-t2-spec-text\">be able to define first, second and third ionisation energies and understand that all ionisation energies are endothermic<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.10<\/div>\n            <div class=\"ols-t2-spec-text\">understand how ionisation energies are influenced by the number of protons in the nucleus, the electron shielding and the sub-shell from which the electron is removed<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row\">\n            <div class=\"ols-t2-spec-code\">2.17<\/div>\n            <div class=\"ols-t2-spec-text\">be able to represent data, in a graphical form, including the use of logarithms of first ionisation energies on a graph, for elements 1 to 36 and hence explain the meaning of the term periodic property<\/div>\n          <\/div>\n          <div class=\"ols-t2-spec-row ols-t2-spec-row--mid\">\n            <div class=\"ols-t2-spec-code\">2.18<\/div>\n            <div class=\"ols-t2-spec-text\">\n              <div style=\"margin:0 0 12px;\">be able to explain:<\/div>\n              <div class=\"ols-t2-spec-sub-list\">\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">the trends in melting and boiling temperatures of the elements of Periods 2 and 3 of the Periodic Table in terms of the structure of the element and the bonding between its atoms or molecules<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">the general increase and the specific trends in ionisation energy of the elements across Periods 2 and 3 of the Periodic Table<\/div>\n                <\/div>\n                <div class=\"ols-t2-spec-sub-row\">\n                  <div class=\"ols-t2-spec-sub-code\">iii<\/div>\n                  <div class=\"ols-t2-spec-sub-text\">the decrease in first ionisation energy down a group<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Revision Notes \/ A Level Chemistry \/ Edexcel International \/ Topic 2 Atomic Structure and the Periodic Table Edexcel International A Level Chemistry Topic 2Atomic Structure&amp; The Periodic Table Topic 2 builds the foundation for atomic structure, isotopes, mass spectrometry, the quantum model, electronic configuration, ionisation energy and periodic trends. These ideas explain how evidence [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":1786,"menu_order":1,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3985","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/3985","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=3985"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/3985\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/1786"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=3985"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}