{"id":7920,"date":"2026-09-14T21:37:43","date_gmt":"2026-09-14T20:37:43","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/"},"modified":"2026-09-14T22:00:26","modified_gmt":"2026-09-14T21:00:26","slug":"topic-9-the-periodic-table-chemical-periodicity","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/","title":{"rendered":"Topic 9 The Periodic Table: Chemical Periodicity"},"content":{"rendered":"\n<div class=\"ols-cie9-page\">\n\n  <aside class=\"ols-sidebar\">\n  <div class=\"ols-sidebar-header\">\n    <h3>Revision Notes<\/h3>\n    <p>Cambridge International AS Level Chemistry<\/p>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>Topic 9 Chemical Periodicity<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/\">Topic overview<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/periodic-trends\/\">9.1 Periodic Trends<\/a><\/li>\n<li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-1-atomic-structure\/atomic-and-ionic-radii\/\">Atomic and Ionic Radii (Topic 1)<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-1-atomic-structure\/ionisation-energy\/\">Ionisation Energy (Topic 1)<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-4-states-of-matter\/structure-types\/\">Structure Types (Topic 4)<\/a><\/li>\n    <\/ul>\n  <\/div>\n  <div class=\"ols-topic-group\">\n    <h4>Other Topics<\/h4>\n    <ul class=\"ols-topic-list\">\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-1-atomic-structure\/\">Topic 1 Atomic Structure<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-3-chemical-bonding\/\">Topic 3 Chemical Bonding<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-4-states-of-matter\/\">Topic 4 States of Matter<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-13-an-introduction-to-as-level-organic-chemistry\/\">Topic 13 Introduction to Organic Chemistry<\/a><\/li>\n      <li><a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-14-hydrocarbons\/\">Topic 14 Hydrocarbons<\/a><\/li>\n    <\/ul>\n 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<div class=\"ols-cie9-container\">\n      <nav class=\"ols-cie9-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\/cie\/\">Cambridge International (CIE)<\/a> \/\n          <span>Topic 9 The Periodic Table: Chemical Periodicity<\/span>\n        <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-cie9-intro\">\n    <div class=\"ols-cie9-container\">\n      <div class=\"ols-cie9-intro-inner\">\n        <div>\n          <div class=\"ols-cie9-eyebrow\">Cambridge International AS Level Chemistry<\/div>\n          <h1>Topic 9<br>The Periodic Table: Chemical Periodicity<\/h1>\n          <div class=\"ols-cie9-accent-bar\"><\/div>\n          <p class=\"ols-cie9-intro-lead\">Topic 9 covers the periodicity of physical properties across Period 3 (atomic and ionic radius, melting point, electrical conductivity), the reactions of the Period 3 elements and their oxides and chlorides, and using periodicity to predict the properties of unknown elements. These pages cover the physical periodicity of 9.1; the oxides and chlorides (9.2) and predictions (9.3) follow with a later set.<\/p>\n        <\/div>\n        <div class=\"ols-cie9-info-grid\">\n          <div class=\"ols-cie9-info-card\"><div class=\"ols-cie9-info-card-label\">Exam Papers<\/div><div class=\"ols-cie9-info-card-value\">Papers 1 &amp; 2<\/div><div class=\"ols-cie9-info-card-sub\">9701\/1 and 9701\/2 (AS Level)<\/div><\/div>\n          <div class=\"ols-cie9-info-card\"><div class=\"ols-cie9-info-card-label\">Learning Outcomes<\/div><div class=\"ols-cie9-info-card-value\">9.1.1 &#8211; 9.3.2<\/div><div class=\"ols-cie9-info-card-sub\">3 parts<\/div><\/div>\n          <div class=\"ols-cie9-info-card\"><div class=\"ols-cie9-info-card-label\">Topic Parts<\/div><div class=\"ols-cie9-info-card-value\">1 of 3 live<\/div><div class=\"ols-cie9-info-card-sub\">9.1 Physical periodicity<\/div><\/div>\n          <div class=\"ols-cie9-info-card\"><div class=\"ols-cie9-info-card-label\">Exam Board<\/div><div class=\"ols-cie9-info-card-value\">Cambridge<\/div><div class=\"ols-cie9-info-card-sub\">CIE 9701 (2025-2027)<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-cie9-topics\">\n    <div class=\"ols-cie9-container\">\n      <div class=\"ols-cie9-section-header\">\n        <h2 class=\"ols-cie9-section-title\">Revision Notes<\/h2>\n        <p class=\"ols-cie9-section-sub\">Work through each part of Cambridge Topic 9 in a structured sequence.<\/p>\n      <\/div>\n      <div class=\"ols-cie9-cards-grid\">\n        <!-- Card 1: 9.1 Periodic Trends -->\n        <a class=\"ols-cie9-card ols-cie9-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/periodic-trends\/\">\n          <div class=\"ols-cie9-card-img-wrap\">\n            <div class=\"ols-cie9-visual ols-cie9-visual--shapes\">\n              <div class=\"ols-cie9-visual-panel\">\n                <div class=\"ols-cie9-visual-kicker\">Period 3<\/div>\n                <div class=\"ols-cie9-visual-main\">Periodic<br>Trends<\/div>\n                <div class=\"ols-cie9-config-line\" aria-hidden=\"true\"><span>Na \u2192 Ar<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie9-card-num\">1<\/div>\n          <\/div>\n          <div class=\"ols-cie9-card-body\">\n            <p class=\"ols-cie9-card-title\">9.1 Periodic Trends<\/p>\n            <p class=\"ols-cie9-card-desc\">Atomic radius, ionisation energy, melting point and conductivity across Period 3 explained by structure and bonding (9.1.1, 9.1.2).<\/p>\n            <span class=\"ols-cie9-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <a class=\"ols-cie9-card ols-cie9-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-1-atomic-structure\/atomic-and-ionic-radii\/\">\n          <div class=\"ols-cie9-card-img-wrap\">\n            <div class=\"ols-cie9-visual ols-cie9-visual--shapes\">\n              <div class=\"ols-cie9-visual-panel\">\n                <div class=\"ols-cie9-visual-kicker\">Radii<\/div>\n                <div class=\"ols-cie9-visual-main\">Atomic and<br>Ionic Radii<\/div>\n                <div class=\"ols-cie9-config-line\" aria-hidden=\"true\"><span>Na\u207a &lt; Na &lt; Cl\u207b<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie9-card-num\">2<\/div>\n          <\/div>\n          <div class=\"ols-cie9-card-body\">\n            <p class=\"ols-cie9-card-title\">Atomic and Ionic Radii (Topic 1)<\/p>\n            <p class=\"ols-cie9-card-desc\">The periodicity of atomic and ionic radius across Radii, including the isoelectronic ions (9.1.1-a, 9.1.1-b), on the Topic 1 pages.<\/p>\n            <span class=\"ols-cie9-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 2: Ionisation Energy (Topic 1) -->\n        <a class=\"ols-cie9-card ols-cie9-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-1-atomic-structure\/ionisation-energy\/\">\n          <div class=\"ols-cie9-card-img-wrap\">\n            <div class=\"ols-cie9-visual ols-cie9-visual--polarity\">\n              <div class=\"ols-cie9-visual-panel\">\n                <div class=\"ols-cie9-visual-kicker\">Evidence<\/div>\n                <div class=\"ols-cie9-visual-main\">Ionisation<br>Energy<\/div>\n                <div class=\"ols-cie9-config-line\" aria-hidden=\"true\"><span>X(g) \u2192 X\u207a(g) + e\u207b<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie9-card-num\">3<\/div>\n          <\/div>\n          <div class=\"ols-cie9-card-body\">\n            <p class=\"ols-cie9-card-title\">Ionisation Energy (Topic 1)<\/p>\n            <p class=\"ols-cie9-card-desc\">The ionisation energy trends across Period 3 and down a group, on the Topic 1 pages (1.4.3).<\/p>\n            <span class=\"ols-cie9-card-cta\">Start revising<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><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 3: 9.2 Period 3 Oxides and Chlorides -->\n        <div class=\"ols-cie9-card ols-cie9-card--soon\">\n          <div class=\"ols-cie9-card-img-wrap\">\n            <div class=\"ols-cie9-visual ols-cie9-visual--giant\">\n              <div class=\"ols-cie9-visual-panel\">\n                <div class=\"ols-cie9-visual-kicker\">Reactions<\/div>\n                <div class=\"ols-cie9-visual-main\">Oxides and<br>Chlorides<\/div>\n                <div class=\"ols-cie9-config-line\" aria-hidden=\"true\"><span>Na\u2082O SiCl\u2084<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie9-card-num\">4<\/div>\n            <span class=\"ols-cie9-card-status ols-cie9-card-status--soon\">Coming soon<\/span>\n          <\/div>\n          <div class=\"ols-cie9-card-body\">\n            <p class=\"ols-cie9-card-title\">9.2 Period 3 Oxides and Chlorides<\/p>\n            <p class=\"ols-cie9-card-desc\">Reactions of the elements with oxygen, chlorine and water, and the acid-base behaviour of the oxides and chlorides. Coming with a later set.<\/p>\n            <span class=\"ols-cie9-card-cta\">In preparation<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><\/span>\n          <\/div>\n        <\/div>\n\n        <!-- Card 4: 9.3 Predicting Properties -->\n        <div class=\"ols-cie9-card ols-cie9-card--soon\">\n          <div class=\"ols-cie9-card-img-wrap\">\n            <div class=\"ols-cie9-visual ols-cie9-visual--ionic\">\n              <div class=\"ols-cie9-visual-panel\">\n                <div class=\"ols-cie9-visual-kicker\">Predict<\/div>\n                <div class=\"ols-cie9-visual-main\">Using<br>Periodicity<\/div>\n                <div class=\"ols-cie9-config-line\" aria-hidden=\"true\"><span>? \u2192 group<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-cie9-card-num\">5<\/div>\n            <span class=\"ols-cie9-card-status ols-cie9-card-status--soon\">Coming soon<\/span>\n          <\/div>\n          <div class=\"ols-cie9-card-body\">\n            <p class=\"ols-cie9-card-title\">9.3 Predicting Properties<\/p>\n            <p class=\"ols-cie9-card-desc\">Deducing the nature and position of unknown elements from their properties. Coming with a later set.<\/p>\n            <span class=\"ols-cie9-card-cta\">In preparation<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><\/span>\n          <\/div>\n        <\/div>\n\n      \n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION -->\n  <section class=\"ols-cie9-spec-section\">\n    <div class=\"ols-cie9-container\">\n      <div class=\"ols-cie9-spec-wrap\">\n        <div class=\"ols-cie9-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-cie9-spec-heading\">Topic 9 The Periodic Table: Chemical Periodicity &#8211; Cambridge International AS Level Chemistry<\/h2>\n        <p class=\"ols-cie9-spec-intro-text\">The following Cambridge learning outcomes state what candidates should be able to do for Topic 9. Wording is taken from the Cambridge International AS &amp; A Level Chemistry 9701 syllabus (2025-2027).<\/p>\n\n        <h3 class=\"ols-cie9-spec-group-title\">9.1 Periodicity of physical properties of the elements in Period 3<\/h3>\n<div class=\"ols-cie9-spec-rows\">\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--light\"><div class=\"ols-cie9-spec-code\">9.1.1<\/div><div class=\"ols-cie9-spec-text\">describe qualitatively (and indicate the periodicity in) the variations in atomic radius, ionic radius, melting point and electrical conductivity of the elements<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--mid\"><div class=\"ols-cie9-spec-code ols-cie9-spec-code--mid\">9.1.2<\/div><div class=\"ols-cie9-spec-text\">explain the variation in melting point and electrical conductivity in terms of the structure and bonding of the elements<\/div><\/div>\n<\/div>\n<h3 class=\"ols-cie9-spec-group-title\">9.2 Periodicity of chemical properties of the elements in Period 3<\/h3>\n<div class=\"ols-cie9-spec-rows\">\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--light\"><div class=\"ols-cie9-spec-code\">9.2.1<\/div><div class=\"ols-cie9-spec-text\">describe, and write equations for, the reactions of the elements with oxygen (to give Na2O, MgO, Al2O3, P4O10, SO2), chlorine (to give NaCl, MgCl2, AlCl3, SiCl4, PCl5) and water (Na and Mg only)<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--mid\"><div class=\"ols-cie9-spec-code ols-cie9-spec-code--mid\">9.2.2<\/div><div class=\"ols-cie9-spec-text\">state and explain the variation in the oxidation number of the oxides (Na2O, MgO, Al2O3, P4O10, SO2 and SO3 only) and chlorides (NaCl, MgCl2, AlCl3, SiCl4, PCl5 only) in terms of their outer shell (valence shell) electrons<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--light\"><div class=\"ols-cie9-spec-code\">9.2.3<\/div><div class=\"ols-cie9-spec-text\">describe, and write equations for, the reactions, if any, of the oxides Na2O, MgO, Al2O3, SiO2, P4O10, SO2 and SO3 with water including the likely pHs of the solutions obtained<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--mid\"><div class=\"ols-cie9-spec-code ols-cie9-spec-code--mid\">9.2.4<\/div><div class=\"ols-cie9-spec-text\">describe, explain, and write equations for, the acid\/base behaviour of the oxides Na2O, MgO, Al2O3, P4O10, SO2 and SO3 and the hydroxides NaOH, Mg(OH)2 and Al(OH)3 including, where relevant, amphoteric behaviour in reactions with acids and bases (sodium hydroxide only)<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--light\"><div class=\"ols-cie9-spec-code\">9.2.5<\/div><div class=\"ols-cie9-spec-text\">describe, explain, and write equations for, the reactions of the chlorides NaCl, MgCl2, AlCl3, SiCl4, PCl5 with water including the likely pHs of the solutions obtained<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--mid\"><div class=\"ols-cie9-spec-code ols-cie9-spec-code--mid\">9.2.6<\/div><div class=\"ols-cie9-spec-text\">explain the variations and trends in 9.2.2, 9.2.3, 9.2.4 and 9.2.5 in terms of bonding and electronegativity<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--light\"><div class=\"ols-cie9-spec-code\">9.2.7<\/div><div class=\"ols-cie9-spec-text\">suggest the types of chemical bonding present in the chlorides and oxides from observations of their chemical and physical properties<\/div><\/div>\n<\/div>\n<h3 class=\"ols-cie9-spec-group-title\">9.3 Chemical periodicity of other elements<\/h3>\n<div class=\"ols-cie9-spec-rows\">\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--mid\"><div class=\"ols-cie9-spec-code ols-cie9-spec-code--mid\">9.3.1<\/div><div class=\"ols-cie9-spec-text\">predict the characteristic properties of an element in a given group by using knowledge of chemical periodicity<\/div><\/div>\n<div class=\"ols-cie9-spec-row ols-cie9-spec-row--light\"><div class=\"ols-cie9-spec-code\">9.3.2<\/div><div class=\"ols-cie9-spec-text\">deduce the nature, possible position in the Periodic Table and identity of unknown elements from given information about physical and chemical properties<\/div><\/div>\n<\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n<script type=\"application\/ld+json\">{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"WebPage\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/#webpage\",\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/cie\/topic-9-the-periodic-table-chemical-periodicity\/\",\n      \"name\": \"Topic 9 Chemical Periodicity - 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