{"id":4500,"date":"2026-05-28T05:24:48","date_gmt":"2026-05-28T04:24:48","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/"},"modified":"2026-06-02T04:36:10","modified_gmt":"2026-06-02T03:36:10","slug":"topic-4-inorganic-chemistry-and-the-periodic-table","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/","title":{"rendered":"Topic 4 &#8211; Inorganic Chemistry and The Periodic Table"},"content":{"rendered":"\n<div class=\"ols-t4-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 4 Inorganic Chemistry and The Periodic Table<\/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-4-inorganic-chemistry-and-the-periodic-table\/groups-1-and-2\/\">Groups 1 and 2<\/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-4-inorganic-chemistry-and-the-periodic-table\/group-7-halogens\/\">Group 7 Halogens<\/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-4-inorganic-chemistry-and-the-periodic-table\/inorganic-analysis\/\">Inorganic Analysis<\/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 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margin-top: 10px;\n    }\n\n    .ols-t4-spec-mob-sub-row {\n      background: #ffffff;\n      border: 1px solid rgba(70, 127, 247, 0.15);\n      border-radius: 12px;\n      overflow: hidden;\n    }\n\n    .ols-t4-spec-mob-sub-code {\n      background: #93b5f8;\n      color: #0c2060;\n      font-size: 13px;\n      font-weight: 800;\n      text-align: center;\n      height: 30px;\n      line-height: 30px;\n    }\n\n    .ols-t4-spec-mob-sub-text {\n      padding: 12px 16px;\n      font-size: 14px;\n      font-weight: 300;\n      line-height: 1.8;\n      color: #4b5563;\n    }\n\n    \/* =========================================================\n       RESPONSIVE\n    ========================================================= *\/\n\n    @media (max-width: 1024px) {\n      .ols-t4-cards-grid {\n        grid-template-columns: repeat(2, minmax(0, 1fr));\n      }\n    }\n\n    @media (max-width: 860px) {\n      .ols-t4-intro-inner {\n        grid-template-columns: 1fr;\n        gap: 40px;\n      }\n    }\n\n    @media (max-width: 640px) {\n      .ols-t4-intro {\n        padding: 24px 0 52px;\n      }\n\n      .ols-t4-topics {\n        padding: 52px 0 58px;\n      }\n\n      .ols-t4-cards-grid {\n        grid-template-columns: 1fr;\n        gap: 14px;\n      }\n\n      .ols-t4-spec-section {\n        padding: 52px 0 64px;\n      }\n\n      .ols-t4-spec-wrap {\n        padding: 24px 18px;\n        border-radius: 20px;\n      }\n\n      .ols-t4-info-grid {\n        grid-template-columns: 1fr 1fr;\n      }\n    }\n\n  <\/style>\n\n  <!-- BREADCRUMB BAR - sits above everything -->\n  <div class=\"ols-t4-breadcrumb-bar\">\n    <div class=\"ols-t4-container\">\n      <nav class=\"ols-t4-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 4 Inorganic Chemistry and The Periodic Table<\/span>\n      <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-t4-intro\">\n    <div class=\"ols-t4-container\">\n      <div class=\"ols-t4-intro-inner\">\n        <div>\n          <div class=\"ols-t4-eyebrow\">Edexcel A Level Chemistry<\/div>\n          <h1>Topic 4<br>Inorganic<br>Chemistry and<br>The Periodic Table<\/h1>\n          <div class=\"ols-t4-accent-bar\"><\/div>\n          <p class=\"ols-t4-intro-lead\">Topic 4 develops inorganic chemistry through Group 1, Group 2 and Group 7 trends. Students learn to explain reactivity, thermal stability, flame colours, halogen displacement reactions and the tests used to identify key inorganic ions.<\/p>\n        <\/div>\n        <div class=\"ols-t4-info-grid\">\n          <div class=\"ols-t4-info-card\"><div class=\"ols-t4-info-card-label\">Exam Papers<\/div><div class=\"ols-t4-info-card-value\">Paper 1<\/div><div class=\"ols-t4-info-card-sub\">9CH0\/01<\/div><\/div>\n          <div class=\"ols-t4-info-card\"><div class=\"ols-t4-info-card-label\">Specification Points<\/div><div class=\"ols-t4-info-card-value\">4.1 &#8211; 4.15<\/div><div class=\"ols-t4-info-card-sub\">15 points covered<\/div><\/div>\n          <div class=\"ols-t4-info-card\"><div class=\"ols-t4-info-card-label\">Topic Parts<\/div><div class=\"ols-t4-info-card-value\">3 parts<\/div><div class=\"ols-t4-info-card-sub\">Revision notes available<\/div><\/div>\n          <div class=\"ols-t4-info-card\"><div class=\"ols-t4-info-card-label\">Exam Board<\/div><div class=\"ols-t4-info-card-value\">Edexcel<\/div><div class=\"ols-t4-info-card-sub\">Pearson 9CH0<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-t4-topics\">\n    <div class=\"ols-t4-container\">\n      <div class=\"ols-t4-section-header\">\n        <h2 class=\"ols-t4-section-title\">Revision Notes<\/h2>\n        <p class=\"ols-t4-section-sub\">Work through each part of Edexcel Topic 4 in a structured sequence.<\/p>\n      <\/div>\n      <div class=\"ols-t4-cards-grid\">\n        <!-- Card 1: Groups 1 and 2 -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/groups-1-and-2\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--shape\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">s-block trends<\/div>\n                <div class=\"ols-t4-visual-main\">Groups<br>1 and 2<\/div>\n                <div class=\"ols-t4-visual-sub\">metals, ions and flame tests<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">1<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Groups 1 and 2<\/p>\n            <p class=\"ols-t4-card-desc\">Group 2 reactivity, hydroxide and sulfate solubility, thermal stability, flame colours and experimental procedures.<\/p>\n            <span class=\"ols-t4-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        <!-- Card 2: Group 7 Halogens -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/group-7-halogens\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--amber\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">Halogens<\/div>\n                <div class=\"ols-t4-visual-main\">Group 7<br>Halogens<\/div>\n                <div class=\"ols-t4-molecule-row\" aria-hidden=\"true\"><span class=\"ols-t4-ion\">Cl<sub>2<\/sub><\/span><span class=\"ols-t4-bond\"><\/span><span class=\"ols-t4-ion\">Br<sub>2<\/sub><\/span><span class=\"ols-t4-bond\"><\/span><span class=\"ols-t4-ion\">I<sub>2<\/sub><\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">2<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Group 7 Halogens<\/p>\n            <p class=\"ols-t4-card-desc\">Halogen trends, displacement reactions, disproportionation, hydrogen halides and reactions with sulfuric acid.<\/p>\n            <span class=\"ols-t4-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        <!-- Card 3: Inorganic Analysis -->\n        <a class=\"ols-t4-card ols-t4-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/inorganic-analysis\/\">\n          <div class=\"ols-t4-card-img-wrap\">\n            <div class=\"ols-t4-visual ols-t4-visual--teal\">\n              <div class=\"ols-t4-visual-panel\">\n                <div class=\"ols-t4-visual-kicker\">Ion tests<\/div>\n                <div class=\"ols-t4-visual-main\">Inorganic<br>Analysis<\/div>\n                <div class=\"ols-t4-visual-sub\">observations and ionic equations<\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">3<\/div>\n            <span class=\"ols-t4-card-status ols-t4-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Inorganic Analysis<\/p>\n            <p class=\"ols-t4-card-desc\">Qualitative tests for carbonate, hydrogencarbonate, sulfate and ammonium ions, including ionic equations.<\/p>\n            <span class=\"ols-t4-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      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION SECTION -->\n  <section class=\"ols-t4-spec-section\">\n    <div class=\"ols-t4-container\">\n      <div class=\"ols-t4-spec-desktop\">\n        <div class=\"ols-t4-spec-wrap\">\n          <div class=\"ols-t4-spec-pill\">Specification Coverage<\/div>\n          <h2 class=\"ols-t4-spec-heading\">Topic 4 Inorganic Chemistry and The Periodic Table &#8211; Edexcel A Level Chemistry<\/h2>\n          <p class=\"ols-t4-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 4.<\/p>\n<h3 class=\"ols-t4-spec-group-title\">4A: The elements of Groups 1 and 2<\/h3>\n<div class=\"ols-t4-spec-rows\">\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.1<\/div>\n              <div class=\"ols-t4-spec-text\">understand reasons for the trend in ionisation energy down Group 2<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.2<\/div>\n              <div class=\"ols-t4-spec-text\">understand reasons for the trend in reactivity of the Group 2 elements down the group<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.3<\/div>\n              <div class=\"ols-t4-spec-text\">know the reactions of the elements Mg to Ba in Group 2 with oxygen, chlorine and water<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.4<\/div>\n              <div class=\"ols-t4-spec-text\">know the reactions of the oxides of Group 2 elements with water and dilute acid, and their hydroxides with dilute acid<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.5<\/div>\n              <div class=\"ols-t4-spec-text\">know the trends in solubility of the hydroxides and sulfates of Group 2 elements<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.6<\/div>\n              <div class=\"ols-t4-spec-text\">understand reasons for the trends in thermal stability of the nitrates and the carbonates of the elements in Groups 1 and 2 in terms of the size and charge of the cations involved<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.7<\/div>\n              <div class=\"ols-t4-spec-text\">understand the formation of characteristic flame colours by Group 1 and 2 compounds in terms of electron transitions. Students will be expected to know the flame colours for Groups 1 and 2 compounds.<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.8<\/div>\n              <div class=\"ols-t4-spec-text\">understand experimental procedures to show:<div class=\"ols-t4-spec-sub-list\"><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">i<\/div><div class=\"ols-t4-spec-sub-text\">patterns in thermal decomposition of Group 1 and 2 nitrates and carbonates<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">ii<\/div><div class=\"ols-t4-spec-sub-text\">flame colours in compounds of Group 1 and 2 elements<\/div><\/div><\/div><\/div>\n            <\/div>\n<\/div>\n<h3 class=\"ols-t4-spec-group-title\">4B: The elements of Group 7, halogens<\/h3>\n<div class=\"ols-t4-spec-rows\">\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.9<\/div>\n              <div class=\"ols-t4-spec-text\">understand reasons for the trends in melting and boiling temperatures, physical state at room temperature, and electronegativity for Group 7 elements<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.10<\/div>\n              <div class=\"ols-t4-spec-text\">understand reasons for the trend in reactivity of Group 7 elements down the group<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.11<\/div>\n              <div class=\"ols-t4-spec-text\">understand the trend in reactivity of Group 7 elements in terms of the redox reactions of Cl<sub>2<\/sub>, Br<sub>2<\/sub> and I<sub>2<\/sub> with halide ions in aqueous solution, followed by the addition of an organic solvent<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.12<\/div>\n              <div class=\"ols-t4-spec-text\">understand, in terms of changes in oxidation number, the following reactions of the halogens:<div class=\"ols-t4-spec-sub-list\"><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">i<\/div><div class=\"ols-t4-spec-sub-text\">oxidation reactions with Group 1 and 2 metals<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">ii<\/div><div class=\"ols-t4-spec-sub-text\">the disproportionation reaction of chlorine with water and the use of chlorine in water treatment<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">iii<\/div><div class=\"ols-t4-spec-sub-text\">the disproportionation reaction of chlorine with cold, dilute aqueous sodium hydroxide to form bleach<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">iv<\/div><div class=\"ols-t4-spec-sub-text\">the disproportionation reaction of chlorine with hot alkali<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">v<\/div><div class=\"ols-t4-spec-sub-text\">reactions analogous to those specified above<\/div><\/div><\/div><\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.13<\/div>\n              <div class=\"ols-t4-spec-text\">understand the following reactions:<div class=\"ols-t4-spec-sub-list\"><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">i<\/div><div class=\"ols-t4-spec-sub-text\">solid Group 1 halides with concentrated sulfuric acid, to illustrate the trend in reducing ability of the hydrogen halides<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">ii<\/div><div class=\"ols-t4-spec-sub-text\">precipitation reactions of the aqueous anions Cl<sup>&#8211;<\/sup>, Br<sup>&#8211;<\/sup> and I<sup>&#8211;<\/sup> with aqueous silver nitrate solution, followed by aqueous ammonia solution<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">iii<\/div><div class=\"ols-t4-spec-sub-text\">hydrogen halides with ammonia and with water, to produce acids<\/div><\/div><\/div><\/div>\n            <\/div>\n<div class=\"ols-t4-spec-row ols-t4-spec-row--light\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--dark\">4.14<\/div>\n              <div class=\"ols-t4-spec-text\">be able to make predictions about fluorine and astatine and their compounds, in terms of knowledge of trends in halogen chemistry<\/div>\n            <\/div>\n<\/div>\n<h3 class=\"ols-t4-spec-group-title\">4C: Analysis of inorganic compounds<\/h3>\n<div class=\"ols-t4-spec-rows\">\n<div class=\"ols-t4-spec-row ols-t4-spec-row--mid\">\n              <div class=\"ols-t4-spec-code ols-t4-spec-code--mid\">4.15<\/div>\n              <div class=\"ols-t4-spec-text\">know reactions, including ionic equations where appropriate, for identifying:<div class=\"ols-t4-spec-sub-list\"><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">i<\/div><div class=\"ols-t4-spec-sub-text\">carbonate ions, CO<sub>3<\/sub><sup>2-<\/sup>, and hydrogencarbonate ions, HCO<sub>3<\/sub><sup>&#8211;<\/sup>, using an aqueous acid to form carbon dioxide<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">ii<\/div><div class=\"ols-t4-spec-sub-text\">sulfate ions, SO<sub>4<\/sub><sup>2-<\/sup>, using acidified barium chloride solution<\/div><\/div><div class=\"ols-t4-spec-sub-row\"><div class=\"ols-t4-spec-sub-code\">iii<\/div><div class=\"ols-t4-spec-sub-text\">ammonium ions, NH<sub>4<\/sub><sup>+<\/sup>, using sodium hydroxide solution and warming to form ammonia<\/div><\/div><\/div><\/div>\n            <\/div>\n<\/div>\n        <\/div>\n      <\/div>\n      <div class=\"ols-t4-spec-mobile\">\n        <div class=\"ols-t4-spec-wrap\">\n          <div class=\"ols-t4-spec-pill\">Specification Coverage<\/div>\n          <h2 class=\"ols-t4-spec-heading\">Topic 4 Inorganic Chemistry and The Periodic Table &#8211; Edexcel A Level Chemistry<\/h2>\n          <p class=\"ols-t4-spec-intro-text\">The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 4.<\/p>\n<h3 class=\"ols-t4-spec-group-title\">4A: The elements of Groups 1 and 2<\/h3>\n<div class=\"ols-t4-spec-mob-rows\">\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.1<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand reasons for the trend in ionisation energy down Group 2<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.2<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand reasons for the trend in reactivity of the Group 2 elements down the group<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.3<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know the reactions of the elements Mg to Ba in Group 2 with oxygen, chlorine and water<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.4<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know the reactions of the oxides of Group 2 elements with water and dilute acid, and their hydroxides with dilute acid<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.5<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know the trends in solubility of the hydroxides and sulfates of Group 2 elements<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.6<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand reasons for the trends in thermal stability of the nitrates and the carbonates of the elements in Groups 1 and 2 in terms of the size and charge of the cations involved<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.7<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand the formation of characteristic flame colours by Group 1 and 2 compounds in terms of electron transitions. Students will be expected to know the flame colours for Groups 1 and 2 compounds.<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.8<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand experimental procedures to show:<div class=\"ols-t4-spec-mob-sub-list\"><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">i<\/div><div class=\"ols-t4-spec-mob-sub-text\">patterns in thermal decomposition of Group 1 and 2 nitrates and carbonates<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">ii<\/div><div class=\"ols-t4-spec-mob-sub-text\">flame colours in compounds of Group 1 and 2 elements<\/div><\/div><\/div><\/div>\n            <\/div>\n<\/div>\n<h3 class=\"ols-t4-spec-group-title\">4B: The elements of Group 7, halogens<\/h3>\n<div class=\"ols-t4-spec-mob-rows\">\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.9<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand reasons for the trends in melting and boiling temperatures, physical state at room temperature, and electronegativity for Group 7 elements<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.10<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand reasons for the trend in reactivity of Group 7 elements down the group<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.11<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand the trend in reactivity of Group 7 elements in terms of the redox reactions of Cl<sub>2<\/sub>, Br<sub>2<\/sub> and I<sub>2<\/sub> with halide ions in aqueous solution, followed by the addition of an organic solvent<\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.12<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand, in terms of changes in oxidation number, the following reactions of the halogens:<div class=\"ols-t4-spec-mob-sub-list\"><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">i<\/div><div class=\"ols-t4-spec-mob-sub-text\">oxidation reactions with Group 1 and 2 metals<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">ii<\/div><div class=\"ols-t4-spec-mob-sub-text\">the disproportionation reaction of chlorine with water and the use of chlorine in water treatment<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">iii<\/div><div class=\"ols-t4-spec-mob-sub-text\">the disproportionation reaction of chlorine with cold, dilute aqueous sodium hydroxide to form bleach<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">iv<\/div><div class=\"ols-t4-spec-mob-sub-text\">the disproportionation reaction of chlorine with hot alkali<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">v<\/div><div class=\"ols-t4-spec-mob-sub-text\">reactions analogous to those specified above<\/div><\/div><\/div><\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.13<\/div>\n              <div class=\"ols-t4-spec-mob-text\">understand the following reactions:<div class=\"ols-t4-spec-mob-sub-list\"><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">i<\/div><div class=\"ols-t4-spec-mob-sub-text\">solid Group 1 halides with concentrated sulfuric acid, to illustrate the trend in reducing ability of the hydrogen halides<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">ii<\/div><div class=\"ols-t4-spec-mob-sub-text\">precipitation reactions of the aqueous anions Cl<sup>&#8211;<\/sup>, Br<sup>&#8211;<\/sup> and I<sup>&#8211;<\/sup> with aqueous silver nitrate solution, followed by aqueous ammonia solution<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">iii<\/div><div class=\"ols-t4-spec-mob-sub-text\">hydrogen halides with ammonia and with water, to produce acids<\/div><\/div><\/div><\/div>\n            <\/div>\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--light\">\n              <div class=\"ols-t4-spec-mob-code\">4.14<\/div>\n              <div class=\"ols-t4-spec-mob-text\">be able to make predictions about fluorine and astatine and their compounds, in terms of knowledge of trends in halogen chemistry<\/div>\n            <\/div>\n<\/div>\n<h3 class=\"ols-t4-spec-group-title\">4C: Analysis of inorganic compounds<\/h3>\n<div class=\"ols-t4-spec-mob-rows\">\n<div class=\"ols-t4-spec-mob-row ols-t4-spec-mob-row--mid\">\n              <div class=\"ols-t4-spec-mob-code ols-t4-spec-mob-code--mid\">4.15<\/div>\n              <div class=\"ols-t4-spec-mob-text\">know reactions, including ionic equations where appropriate, for identifying:<div class=\"ols-t4-spec-mob-sub-list\"><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">i<\/div><div class=\"ols-t4-spec-mob-sub-text\">carbonate ions, CO<sub>3<\/sub><sup>2-<\/sup>, and hydrogencarbonate ions, HCO<sub>3<\/sub><sup>&#8211;<\/sup>, using an aqueous acid to form carbon dioxide<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">ii<\/div><div class=\"ols-t4-spec-mob-sub-text\">sulfate ions, SO<sub>4<\/sub><sup>2-<\/sup>, using acidified barium chloride solution<\/div><\/div><div class=\"ols-t4-spec-mob-sub-row\"><div class=\"ols-t4-spec-mob-sub-code\">iii<\/div><div class=\"ols-t4-spec-mob-sub-text\">ammonium ions, NH<sub>4<\/sub><sup>+<\/sup>, using sodium hydroxide solution and warming to form ammonia<\/div><\/div><\/div><\/div>\n            <\/div>\n<\/div>\n        <\/div>\n      <\/div>\n    <\/div>\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-4-inorganic-chemistry-and-the-periodic-table\/\",\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\",\n      \"name\": \"Topic 4 Inorganic Chemistry and The Periodic Table - Edexcel A Level Chemistry\",\n      \"description\": \"Topic 4 develops inorganic chemistry through Group 1, Group 2 and Group 7 trends. 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