{"id":4681,"date":"2026-06-01T12:06:07","date_gmt":"2026-06-01T11:06:07","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/groups-1-and-2\/"},"modified":"2026-10-24T19:51:09","modified_gmt":"2026-10-24T18:51:09","slug":"groups-1-and-2","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/groups-1-and-2\/","title":{"rendered":"Groups 1 and 2"},"content":{"rendered":"\n<div class=\"ols-t4-page\">\n\n  <aside class=\"ols-sidebar\">\n  <div class=\"ols-sidebar-header\">\n    <h3>Revision Notes<\/h3>\n    <p>A Level Chemistry<\/p>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Topic 4 Inorganic Chemistry and The Periodic Table<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\">Topic 4 Overview<\/a>\n      <\/li>\n      <li>\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>\n        <ul class=\"ols-subtopic-list\">\n          <li>\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\/trends-down-groups-1-and-2\/\">Trends Down Groups 1 and 2<\/a>\n          <\/li>\n          <li>\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\/reactions-of-the-group-1-and-2-elements\/\">Reactions of the Group 1 and 2 Elements<\/a>\n          <\/li>\n          <li>\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\/oxides-hydroxides-and-carbonates\/\">Oxides, Hydroxides and Carbonates<\/a>\n          <\/li>\n          <li>\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\/solubility-trends-and-the-sulfate-test\/\">Solubility Trends and the Sulfate Test<\/a>\n          <\/li>\n          <li>\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\/thermal-stability-and-flame-colours\/\">Thermal Stability and Flame Colours<\/a>\n          <\/li>\n        <\/ul>\n      <\/li>\n      <li>\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>\n        <ul class=\"ols-subtopic-list\">\n          <li>\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\/trends-in-the-halogens\/\">Trends in the Halogens<\/a>\n          <\/li>\n          <li>\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\/halogens-as-oxidising-agents\/\">Halogens as Oxidising Agents<\/a>\n          <\/li>\n          <li>\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\/disproportionation-reactions-of-chlorine\/\">Disproportionation Reactions of Chlorine<\/a>\n          <\/li>\n          <li>\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\/halide-ions-reducing-agents-and-tests\/\">Halide Ions: Reducing Agents and Tests<\/a>\n          <\/li>\n        <\/ul>\n      <\/li>\n      <li>\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: Tests for Ions<\/a>\n      <\/li>\n    <\/ul>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Next Topics<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/\">Topic 5 Formulae, Equations &amp; Amounts<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-6-organic-chemistry-i\/\">Topic 6 Organic Chemistry I<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-7-modern-analytical-techniques-i\/\">Topic 7 Modern Analytical Techniques I<\/a>\n      <\/li>\n    <\/ul>\n  <\/div>\n<\/aside>\n\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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 }\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      <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\">Topic 4 Inorganic Chemistry and The Periodic Table<\/a> \/\n      <span>Groups 1 and 2<\/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>Groups 1 and 2<\/h1>\n          <div class=\"ols-t4-accent-bar\"><\/div>\n          <p class=\"ols-t4-intro-lead\">\n            The s-block metals are the clearest example of trends down a group. These pages explain the trends in atomic radius, ionisation energy and reactivity, the reactions of the elements and their oxides, hydroxides and carbonates, the solubility and thermal stability patterns, flame colours and the tests for ions. Edexcel Topic 4A examines Group 2 only. The Group 1 metals are kept in the tables because comparing the two groups is the quickest way to see the patterns, but questions will be set on magnesium to barium.\n          <\/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\">9 points covered<\/div><\/div>\n          <div class=\"ols-t4-info-card\"><div class=\"ols-t4-info-card-label\">Sub-topics<\/div><div class=\"ols-t4-info-card-value\">5 lessons<\/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\n        <!-- Card 1: Trends Down 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\/trends-down-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\">Down the group<\/div>\n                  <div class=\"ols-t4-visual-main\">Group Trends<\/div>\n                  <div class=\"ols-t4-visual-sub\">radius, ionisation energy, reactivity<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">1<\/div>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Trends Down Groups 1 and 2<\/p>\n            <p class=\"ols-t4-card-desc\">The trends down Group 2: atomic radius, ionisation energies, melting points and the increase in reactivity down the group.<\/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\n        <!-- Card 2: Reactions of the Group 1 and 2 Elements -->\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\/reactions-of-the-group-1-and-2-elements\/\">\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\">The elements<\/div>\n                  <div class=\"ols-t4-visual-main\">Metal Reactions<\/div>\n                  <div class=\"ols-t4-visual-sub\">oxygen, chlorine, water, acids<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">2<\/div>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Reactions of the Group 1 and 2 Elements<\/p>\n            <p class=\"ols-t4-card-desc\">The reactions of the Group 2 elements with oxygen, chlorine, water, steam and dilute acids, with equations, observations and redox analysis.<\/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\n        <!-- Card 3: Oxides, Hydroxides and Carbonates -->\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\/oxides-hydroxides-and-carbonates\/\">\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\">Bases<\/div>\n                  <div class=\"ols-t4-visual-main\">Oxides and Hydroxides<\/div>\n                  <div class=\"ols-t4-visual-sub\">water, acids, pH, uses<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">3<\/div>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Oxides, Hydroxides and Carbonates<\/p>\n            <p class=\"ols-t4-card-desc\">Group 2 oxides, hydroxides and carbonates: reactions with water and acids, pH trend, and uses of Ca(OH)\u2082, Mg(OH)\u2082 and CaCO\u2083.<\/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\n        <!-- Card 4: Solubility Trends and the Sulfate Test -->\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\/solubility-trends-and-the-sulfate-test\/\">\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\">Opposite trends<\/div>\n                  <div class=\"ols-t4-visual-main\">Solubility Trends<\/div>\n                  <div class=\"ols-t4-visual-sub\">hydroxides up, sulfates down<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">4<\/div>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Solubility Trends and the Sulfate Test<\/p>\n            <p class=\"ols-t4-card-desc\">Group 2 solubility trends: hydroxides and sulfates, Mg(OH)\u2082 and BaSO\u2084, the acidified barium chloride test for sulfate ions and barium meals.<\/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\n        <!-- Card 5: Thermal Stability and Flame Colours -->\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\/thermal-stability-and-flame-colours\/\">\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\">Heat and light<\/div>\n                  <div class=\"ols-t4-visual-main\">Thermal Stability<\/div>\n                  <div class=\"ols-t4-visual-sub\">polarisation and flame colours<\/div>\n                <\/div>\n            <\/div>\n            <div class=\"ols-t4-card-num\">5<\/div>\n          <\/div>\n          <div class=\"ols-t4-card-body\">\n            <p class=\"ols-t4-card-title\">Thermal Stability and Flame Colours<\/p>\n            <p class=\"ols-t4-card-desc\">Thermal stability of Group 1 and 2 nitrates and carbonates, polarisation by the cation, the experiments, and flame colours explained by electron transitions.<\/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\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION SECTION -->\n  <!-- OLS-SMAP -->\n<style>\r\n.ols-smap{--sm-navy:#1C244B;--sm-blue:#467FF7;--sm-teal:#0f8b8d;--sm-muted:#5f6b84;--sm-border:#e3e8f2;margin:44px auto 8px;max-width:1140px;padding:0 20px;font-family:inherit}\r\n.ols-smap-head{display:flex;align-items:baseline;justify-content:space-between;gap:12px;flex-wrap:wrap;margin:0 0 18px}\r\n.ols-smap-head h2{font-size:clamp(22px,2.6vw,28px);font-weight:800;color:var(--sm-navy);margin:0;letter-spacing:-.01em}\r\n.ols-smap-head p{margin:0;color:var(--sm-muted);font-size:14px}\r\n.ols-smap-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,460px),1fr));gap:20px}\r\n.ols-smap-card{display:grid;grid-template-columns:150px 1fr;background:#fff;border:1px solid var(--sm-border);border-radius:22px;overflow:hidden;box-shadow:0 10px 28px rgba(28,36,75,.08);transition:transform 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class=\"ols-smap\" aria-label=\"Summary map\"><div class=\"ols-smap-head\"><h2>Summary map<\/h2><p>Download, print and revise the key facts of this topic at a glance.<\/p><\/div><div class=\"ols-smap-grid\"><article class=\"ols-smap-card\"><div class=\"ols-smap-vis\"><svg viewBox=\"0 0 120 120\" aria-hidden=\"true\"><g fill=\"none\" stroke=\"#ffffff\" stroke-width=\"2.4\" stroke-linecap=\"round\"><circle cx=\"60\" cy=\"60\" r=\"17\"\/><path d=\"M60 43V20M60 77v23M43 60H20M77 60h23M48 48 32 32M72 48l16-16M48 72 32 88M72 72l16 16\"\/><\/g><g fill=\"#ffffff\"><path d=\"M60 16l-4 7h8zM60 104l-4-7h8zM16 60l7-4v8zM104 60l-7-4v8zM29 29l2.5 7.5 5-5zM91 29l-7.5 2.5 5 5zM29 91l7.5-2.5-5-5zM91 91l-2.5-7.5-5 5z\"\/><\/g><g fill=\"#5fd0c9\"><circle cx=\"60\" cy=\"11\" r=\"3\"\/><circle cx=\"109\" cy=\"60\" r=\"3\"\/><\/g><g fill=\"#f2c14e\"><circle cx=\"11\" cy=\"60\" r=\"3\"\/><circle cx=\"96\" cy=\"96\" r=\"3\"\/><\/g><g fill=\"#9db8ff\"><circle cx=\"24\" cy=\"24\" r=\"3\"\/><circle cx=\"60\" cy=\"109\" r=\"3\"\/><\/g><\/svg><\/div><div class=\"ols-smap-body\"><span class=\"ols-smap-kicker\">Summary map \u00b7 PDF<\/span><p class=\"ols-smap-title\">Groups 1 and 2 Map<\/p><p class=\"ols-smap-board\">Edexcel A Level Chemistry \u00b7 Topic 4 Inorganic Chemistry and the Periodic Table \u00b7 Groups 1 and 2<\/p><p class=\"ols-smap-desc\">The whole section on one A4 page: trends down the groups, reactions of the metals, oxides and hydroxides, thermal stability, flame colours, and tests for ions.<\/p><div class=\"ols-smap-row\"><a class=\"ols-smap-btn\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/ols-maps\/map-dom-4a-groups.pdf\" download rel=\"nofollow\"><svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M8 2v8M4.5 6.5 8 10l3.5-3.5M3 13h10\"\/><\/svg>Download the map<\/a><span class=\"ols-smap-meta\">6 key ideas + a data table \u00b7 A4 portrait \u00b7 print ready<\/span><\/div><\/div><\/article><\/div><p class=\"ols-smap-note\">\u00a9 2026 Online Learning System. For personal study: printing is allowed; editing, copying and redistribution are not.<\/p><\/section>\n<!-- \/OLS-SMAP -->\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\">Groups 1 and 2 &#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\">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\">Groups 1 and 2 &#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\">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\/groups-1-and-2\/#webpage\",\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/groups-1-and-2\/\",\n      \"name\": \"Groups 1 and 2\",\n      \"inLanguage\": \"en-GB\",\n      \"breadcrumb\": {\n        \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/groups-1-and-2\/#breadcrumb\"\n      }\n    },\n    {\n      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metals are the clearest example of trends down a group. These pages explain the trends in atomic radius, ionisation energy and reactivity, the [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":4500,"menu_order":1,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-4681","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4681","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=4681"}],"version-history":[{"count":1,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4681\/revisions"}],"predecessor-version":[{"id":23791,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4681\/revisions\/23791"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4500"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=4681"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}