{"id":4497,"date":"2026-05-28T05:24:40","date_gmt":"2026-05-28T04:24:40","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/"},"modified":"2026-05-28T06:03:04","modified_gmt":"2026-05-28T05:03:04","slug":"topic-1-atomic-structure-and-the-periodic-table","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/","title":{"rendered":"Topic 1 &#8211; Atomic Structure and The Periodic Table"},"content":{"rendered":"\n<div class=\"ols-t1-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 1 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\/topic-1-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\/topic-1-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\/topic-1-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\/topic-1-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\/topic-1-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\/topic-1-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\/topic-1-atomic-structure-and-the-periodic-table\/electron-configuration\/\">Electron Configuration<\/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-1-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\/topic-1-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\/topic-1-atomic-structure-and-the-periodic-table\/ionisation-energy\/successive-ionisation-energies\/\">Successive Ionisation Energies<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-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\/topic-1-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\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/periodic-trends\/\">Periodic Trends<\/a>\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\/topic-2-bonding-and-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\/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    <\/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 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     }\n    }\n\n    @media (max-width: 700px) {\n      .ols-t1-spec-row,\n      .ols-t1-spec-sub-row {\n        flex-direction: column;\n      }\n\n      .ols-t1-spec-code,\n      .ols-t1-spec-sub-code {\n        flex: 0 0 auto;\n        min-height: 36px;\n        padding: 10px 12px;\n      }\n    }\n\n    @media (max-width: 640px) {\n      .ols-t1-intro {\n        padding: 24px 0 52px;\n      }\n\n      .ols-t1-container {\n        width: min(1180px, calc(100% - 28px));\n      }\n\n      .ols-t1-topics {\n        padding: 52px 0 58px;\n      }\n\n      .ols-t1-cards-grid {\n        grid-template-columns: 1fr;\n        gap: 14px;\n      }\n\n      .ols-t1-spec-section {\n        padding: 52px 0 64px;\n      }\n\n      .ols-t1-spec-wrap {\n        padding: 24px 18px;\n        border-radius: 20px;\n      }\n\n      .ols-t1-info-grid {\n        grid-template-columns: 1fr 1fr;\n      }\n    }\n\n  <\/style>\n\n  <!-- BREADCRUMB BAR -->\n  <div class=\"ols-t1-breadcrumb-bar\">\n    <div class=\"ols-t1-container\">\n      <nav class=\"ols-t1-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\/\">Edexcel<\/a> \/\n        <span>Topic 1 Atomic Structure and the Periodic Table<\/span>\n      <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t1-intro\">\n    <div class=\"ols-t1-container\">\n      <div class=\"ols-t1-intro-inner\">\n\n        <div>\n          <div class=\"ols-t1-eyebrow\">Edexcel A Level Chemistry (9CH0)<\/div>\n          <h1>Topic 1<br>Atomic Structure<br>&amp; The Periodic Table<\/h1>\n          <div class=\"ols-t1-accent-bar\"><\/div>\n          <p class=\"ols-t1-intro-lead\">\n            Topic 1 establishes the foundation of atomic theory: subatomic particles, isotopes, mass spectrometry, electron configuration, ionisation energies and periodic trends. These ideas underpin every other topic in the course and explain how experimental evidence supports the modern model of the atom.\n          <\/p>\n        <\/div>\n\n        <div class=\"ols-t1-info-grid\">\n          <div class=\"ols-t1-info-card\">\n            <div class=\"ols-t1-info-card-label\">Exam Paper<\/div>\n            <div class=\"ols-t1-info-card-value\">Paper 1<\/div>\n            <div class=\"ols-t1-info-card-sub\">9CH0\/01 &#8211; Advanced Inorganic and Physical Chemistry<\/div>\n          <\/div>\n          <div class=\"ols-t1-info-card\">\n            <div class=\"ols-t1-info-card-label\">Specification Points<\/div>\n            <div class=\"ols-t1-info-card-value\">1 &#8211; 26<\/div>\n            <div class=\"ols-t1-info-card-sub\">26 points covered<\/div>\n          <\/div>\n          <div class=\"ols-t1-info-card\">\n            <div class=\"ols-t1-info-card-label\">Topic Parts<\/div>\n            <div class=\"ols-t1-info-card-value\">5 parts<\/div>\n            <div class=\"ols-t1-info-card-sub\">Revision notes available<\/div>\n          <\/div>\n          <div class=\"ols-t1-info-card\">\n            <div class=\"ols-t1-info-card-label\">Exam Board<\/div>\n            <div class=\"ols-t1-info-card-value\">Edexcel<\/div>\n            <div class=\"ols-t1-info-card-sub\">Pearson 9CH0<\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-t1-topics\">\n    <div class=\"ols-t1-container\">\n\n      <div class=\"ols-t1-section-header\">\n        <h2 class=\"ols-t1-section-title\">Revision Notes<\/h2>\n        <p class=\"ols-t1-section-sub\">Select a section to begin revising.<\/p>\n      <\/div>\n\n      <div class=\"ols-t1-cards-grid\">\n\n        <!-- Card 1: Atomic Structure -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/atomic-structure\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--atom\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Atoms and isotopes<\/div>\n                <div class=\"ols-t1-atom-diagram\" aria-hidden=\"true\">\n                  <span class=\"ols-t1-atom-nucleus\"><\/span>\n                  <span class=\"ols-t1-atom-electron e1\"><\/span>\n                  <span class=\"ols-t1-atom-electron e2\"><\/span>\n                <\/div>\n                <div class=\"ols-t1-visual-main\">Atomic<br>Structure<\/div>\n                <div class=\"ols-t1-visual-sub\">protons, neutrons, electrons and isotopes<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t1-card-num\">1<\/div>\n            <span class=\"ols-t1-card-status ols-t1-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t1-card-body\">\n            <p class=\"ols-t1-card-title\">Atomic Structure<\/p>\n            <p class=\"ols-t1-card-desc\">Subatomic particles, relative mass and charge, atomic number, mass number, isotopes, relative isotopic mass and relative atomic mass.<\/p>\n            <span class=\"ols-t1-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-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/mass-spectrometry\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--mass-spec\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Spectra and abundance<\/div>\n                <div class=\"ols-t1-ms-line\" aria-hidden=\"true\">\n                  <span class=\"ols-t1-ms-peak p1\"><\/span>\n                  <span class=\"ols-t1-ms-peak p2\"><\/span>\n                  <span class=\"ols-t1-ms-peak p3\"><\/span>\n                <\/div>\n                <div class=\"ols-t1-visual-main\">Mass<br>Spectrometry<\/div>\n                <div class=\"ols-t1-visual-sub\">RAM, diatomic spectra and molecular ions<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t1-card-num\">2<\/div>\n            <span class=\"ols-t1-card-status ols-t1-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t1-card-body\">\n            <p class=\"ols-t1-card-title\">Mass Spectrometry<\/p>\n            <p class=\"ols-t1-card-desc\">Interpreting mass spectra, calculating relative atomic mass from isotope abundance, predicting diatomic spectra and determining relative molecular mass.<\/p>\n            <span class=\"ols-t1-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: Electron Configuration -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/electron-configuration\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--electron\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Orbitals and subshells<\/div>\n                <div class=\"ols-t1-orbital\" aria-hidden=\"true\">\n                  <span><\/span>\n                  <span><\/span>\n                <\/div>\n                <div class=\"ols-t1-visual-main\">Electron<br>Configuration<\/div>\n                <div class=\"ols-t1-visual-sub\">s, p, d subshells, orbital notation and blocks<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t1-card-num\">3<\/div>\n            <span class=\"ols-t1-card-status ols-t1-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t1-card-body\">\n            <p class=\"ols-t1-card-title\">Electron Configuration<\/p>\n            <p class=\"ols-t1-card-desc\">Quantum shells, s and p orbital shapes, sub-shells, electrons-in-boxes notation, electronic configurations up to Z = 36 and s, p, d block classification.<\/p>\n            <span class=\"ols-t1-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-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/ionisation-energy\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--ionisation\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Energy and shielding<\/div>\n                <div class=\"ols-t1-ie-arrow\" aria-hidden=\"true\"><span class=\"ols-t1-ie-dot\"><\/span><\/div>\n                <div class=\"ols-t1-visual-main\">Ionisation<br>Energy<\/div>\n                <div class=\"ols-t1-visual-sub\">first IE, successive IE, proton number and shielding<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t1-card-num\">4<\/div>\n            <span class=\"ols-t1-card-status ols-t1-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t1-card-body\">\n            <p class=\"ols-t1-card-title\">Ionisation Energy<\/p>\n            <p class=\"ols-t1-card-desc\">First and successive ionisation energies, influence of proton number, electron shielding and sub-shell, and evidence for electronic structure.<\/p>\n            <span class=\"ols-t1-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 5: Periodic Trends -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-1-atomic-structure-and-the-periodic-table\/periodic-trends\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--periodic\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Repeating patterns<\/div>\n                <div class=\"ols-t1-period-bars\" aria-hidden=\"true\">\n                  <span class=\"ols-t1-period-bar\"><\/span>\n                  <span class=\"ols-t1-period-bar\"><\/span>\n                  <span class=\"ols-t1-period-bar\"><\/span>\n                  <span class=\"ols-t1-period-bar\"><\/span>\n                  <span class=\"ols-t1-period-bar\"><\/span>\n                  <span class=\"ols-t1-period-bar\"><\/span>\n                <\/div>\n                <div class=\"ols-t1-visual-main\">Periodic<br>Trends<\/div>\n                <div class=\"ols-t1-visual-sub\">melting points, ionisation energy and periodicity<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t1-card-num\">5<\/div>\n            <span class=\"ols-t1-card-status ols-t1-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t1-card-body\">\n            <p class=\"ols-t1-card-title\">Periodic Trends<\/p>\n            <p class=\"ols-t1-card-desc\">Periodicity, trends in melting and boiling temperatures of periods 2 and 3, ionisation energy trends and using data to illustrate periodic properties.<\/p>\n            <span class=\"ols-t1-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-t1-spec-section\">\n    <div class=\"ols-t1-container\">\n      <div class=\"ols-t1-spec-wrap\">\n        <div class=\"ols-t1-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-t1-spec-heading\">Topic 1 Atomic Structure and the Periodic Table &#8211; Edexcel A Level Chemistry (9CH0)<\/h2>\n        <p class=\"ols-t1-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 1. All points are assessed in Paper 1 (9CH0\/01).<\/p>\n\n        <h3 class=\"ols-t1-spec-group-title\">Atomic Structure<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1<\/div>\n            <div class=\"ols-t1-spec-text\">know the structure of an atom in terms of electrons, protons and neutrons<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">2<\/div>\n            <div class=\"ols-t1-spec-text\">know the relative mass and relative charge of protons, neutrons and electrons<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">3<\/div>\n            <div class=\"ols-t1-spec-text\">know what is meant by the terms atomic (proton) number and mass number<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">4<\/div>\n            <div class=\"ols-t1-spec-text\">be able to determine the number of each type of sub-atomic particle in an atom, molecule or ion from the atomic (proton) number and mass number<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">5<\/div>\n            <div class=\"ols-t1-spec-text\">understand the term isotopes<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">6<\/div>\n            <div class=\"ols-t1-spec-text\">be able to define the terms relative isotopic mass and relative atomic mass, based on the \u00b9\u00b2C scale<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">7<\/div>\n            <div class=\"ols-t1-spec-text\">understand the terms relative molecular mass and relative formula mass, including calculating these values from relative atomic masses. The term relative formula mass should be used for compounds with giant structures.<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">Mass Spectrometry<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">8<\/div>\n            <div class=\"ols-t1-spec-text\">be able to analyse and interpret data from mass spectrometry to calculate relative atomic mass from relative abundance of isotopes and vice versa<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">9<\/div>\n            <div class=\"ols-t1-spec-text\">be able to predict the mass spectra, including relative peak heights, for diatomic molecules, including chlorine<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">10<\/div>\n            <div class=\"ols-t1-spec-text\">understand how mass spectrometry can be used to determine the relative molecular mass of a molecule. Limited to the m\/z value for the molecular ion, M\u207a, giving the relative molecular mass of the molecule.<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">Electron Configuration<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row ols-t1-spec-row--mid\">\n            <div class=\"ols-t1-spec-code\">15<\/div>\n            <div class=\"ols-t1-spec-text\">\n              <div style=\"margin:0 0 12px;\">understand how ideas about electronic configuration developed from:<\/div>\n              <div class=\"ols-t1-spec-sub-list\">\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">the fact that atomic emission spectra provide evidence for the existence of quantum shells<\/div>\n                <\/div>\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">the fact 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-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">iii<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">the fact 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-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">16<\/div>\n            <div class=\"ols-t1-spec-text\">know the number of electrons that can fill the first four quantum shells<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">17<\/div>\n            <div class=\"ols-t1-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-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">18<\/div>\n            <div class=\"ols-t1-spec-text\">know the shape of an s-orbital and a p-orbital<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">19<\/div>\n            <div class=\"ols-t1-spec-text\">know the number of electrons that occupy s, p and d sub-shells<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">20<\/div>\n            <div class=\"ols-t1-spec-text\">know that electrons fill sub-shells singly, before pairing up, and that two electrons in the same orbital must have opposite spins<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row ols-t1-spec-row--mid\">\n            <div class=\"ols-t1-spec-code\">21<\/div>\n            <div class=\"ols-t1-spec-text\">\n              <div style=\"margin:0 0 12px;\">be able to predict the electronic configurations, using 1s notation and electrons-in-boxes notation, of:<\/div>\n              <div class=\"ols-t1-spec-sub-list\">\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">atoms, given the atomic number Z, up to Z = 36<\/div>\n                <\/div>\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">ions, given the atomic number Z, and the ionic charge, for s and p block ions only, up to Z = 36<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">22<\/div>\n            <div class=\"ols-t1-spec-text\">know that elements can be classified as s, p and d-block elements<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">23<\/div>\n            <div class=\"ols-t1-spec-text\">understand that electronic configuration determines the chemical properties of an element<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">Ionisation Energy<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">11<\/div>\n            <div class=\"ols-t1-spec-text\">be able to define the terms first ionisation energy and successive ionisation energies<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">12<\/div>\n            <div class=\"ols-t1-spec-text\">understand how ionisation energies are influenced by the number of protons, the electron shielding and the electron sub-shell from which the electron is removed<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">13<\/div>\n            <div class=\"ols-t1-spec-text\">understand reasons for the general increase in first ionisation energy across a period<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">14<\/div>\n            <div class=\"ols-t1-spec-text\">understand reasons for the decrease in first ionisation energy down a group<\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">Periodic Trends<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">24<\/div>\n            <div class=\"ols-t1-spec-text\">understand periodicity in terms of a repeating pattern across different periods<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row ols-t1-spec-row--mid\">\n            <div class=\"ols-t1-spec-code\">25<\/div>\n            <div class=\"ols-t1-spec-text\">\n              <div style=\"margin:0 0 12px;\">understand reasons for the trends in the following properties of the elements from periods 2 and 3 of the Periodic Table:<\/div>\n              <div class=\"ols-t1-spec-sub-list\">\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">i<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">the melting and boiling temperatures of the elements, based on given data, in terms of structure and bonding<\/div>\n                <\/div>\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">ii<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">ionisation energy based on given data or recall of the plots of ionisation energy versus atomic number<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">26<\/div>\n            <div class=\"ols-t1-spec-text\">be able to illustrate periodicity using data, including electronic configurations, atomic radii, melting and boiling temperatures and first ionisation energies<\/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 \/ Topic 1 Atomic Structure and the Periodic Table Edexcel A Level Chemistry (9CH0) Topic 1Atomic Structure&amp; The Periodic Table Topic 1 establishes the foundation of atomic theory: subatomic particles, isotopes, mass spectrometry, electron configuration, ionisation energies and periodic trends. These ideas underpin every other topic in [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":1784,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"productId":0,"courseId":0,"footnotes":""},"class_list":["post-4497","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4497","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=4497"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4497\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/1784"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=4497"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}