{"id":3998,"date":"2026-05-21T07:02:45","date_gmt":"2026-05-21T06:02:45","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/"},"modified":"2026-05-24T08:25:05","modified_gmt":"2026-05-24T07:25:05","slug":"topic-1-formulae-equations-and-amount-of-substance","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/","title":{"rendered":"Topic 1 Formulae, Equations and Amount of Substance"},"content":{"rendered":"\n<div class=\"ols-t1-page\">\n\n  <style>\n    @import url('https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@300;400;500;600;700;800&display=swap');\n\n    .ols-t1-page,\n    .ols-t1-page * {\n      box-sizing: border-box;\n    }\n\n    .ols-t1-page {\n      --ols-navy: #1C244B;\n      --ols-blue: #467FF7;\n      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<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 Formulae, Equations and Amount of Substance<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/atoms-elements-and-molecules\/\">Atoms, Elements and Molecules<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/equations-and-reaction-types\/\">Equations and Reaction Types<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/equations-and-reaction-types\/writing-chemical-equations\/\">Writing Chemical Equations<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/equations-and-reaction-types\/typical-reactions-of-acids\/\">Typical Reactions of Acids<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/equations-and-reaction-types\/ionic-equations\/\">Ionic Equations<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/\">Mole Calculations<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/comparing-masses-of-substances\/\">Comparing Masses of Substances<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/calculations-involving-moles\/\">Calculations involving Moles<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/calculations-using-reacting-masses\/\">Calculations using Reacting Masses<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/the-yield-of-a-reaction\/\">The Yield of a Reaction<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/atom-economy\/\">Atom Economy<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/empirical-and-molecular-formulae\/\">Empirical and Molecular Formulae<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/empirical-and-molecular-formulae\/empirical-formulae\/\">Empirical Formulae<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/empirical-and-molecular-formulae\/molecular-formulae\/\">Molecular Formulae<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/calculations-with-solutions-and-gases\/\">Calculations with Solutions and Gases<\/a>\r\n\r\n        <ul class=\"ols-subtopic-list\">\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/calculations-with-solutions-and-gases\/molar-volume-calculations\/\">Molar Volume Calculations<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/calculations-with-solutions-and-gases\/concentrations-of-solutions\/\">Concentrations of Solutions<\/a>\r\n          <\/li>\r\n          <li>\r\n            <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/calculations-with-solutions-and-gases\/concentrations-in-ppm\/\">Concentrations in PPM<\/a>\r\n          <\/li>\r\n        <\/ul>\r\n      <\/li>\r\n    <\/ul>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Next Topics<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-2-atomic-structure-and-the-periodic-table\/\">Atomic Structure and The Periodic Table<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-3-bonding-structure\/\">Bonding &amp; Structure<\/a>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-4-organic-chemistry-and-alkanes\/\">Organic Chemistry &amp; Alkanes<\/a>\r\n      <\/li>\r\n    <\/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(\/\\\/+$|\\s+$\/g, '')\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 currentPath = normalisePath(window.location.pathname);\r\n    var links = sidebar.querySelectorAll('a[href]');\r\n    var matched = null;\r\n    var matchedLength = 0;\r\n\r\n    sidebar.querySelectorAll('.active, .active-main, .parent-active').forEach(function(item) {\r\n      item.classList.remove('active', 'active-main', 'parent-active');\r\n    });\r\n\r\n    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'1');\r\n        }\r\n      }\r\n    }\r\n\r\n    return true;\r\n  }\r\n\r\n  if (!highlightActive()) {\r\n    document.addEventListener('DOMContentLoaded', highlightActive);\r\n  }\r\n})();\r\n<\/script>\r\n\n\n\n  <!-- BREADCRUMB BAR - sits above everything -->\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-international\/\">Edexcel International<\/a> \/\n        <span>Topic 1 Formulae, Equations and Amount of Substance<\/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 International A Level Chemistry<\/div>\n          <h1>Topic 1<br>Formulae, Equations<br>&amp; Amount of Substance<\/h1>\n          <div class=\"ols-t1-accent-bar\"><\/div>\n          <p class=\"ols-t1-intro-lead\">\n            Topic 1 builds the calculation and chemical language foundation for A Level Chemistry. It covers atoms, elements, ions, molecules, compounds, empirical formulae, molecular formulae, balanced equations, reacting masses, solution concentrations, gas volumes, percentage yield and atom economy.\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 Unit<\/div>\n            <div class=\"ols-t1-info-card-value\">Unit 1<\/div>\n            <div class=\"ols-t1-info-card-sub\">WCH11\/01 &#8211; IAS<\/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\">1.1 &#8211; 1.12<\/div>\n            <div class=\"ols-t1-info-card-sub\">12 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 IAL<\/div>\n            <div class=\"ols-t1-info-card-sub\">Pearson International<\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-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      <\/div>\n\n      <div class=\"ols-t1-cards-grid\">\n\n        <!-- Card 1: Atoms, Elements and Molecules -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/atoms-elements-and-molecules\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--particles\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Chemical language<\/div>\n                <div class=\"ols-t1-particle-diagram\" aria-hidden=\"true\">\n                  <span class=\"ols-t1-particle-dot d1\"><\/span>\n                  <span class=\"ols-t1-particle-dot d2\"><\/span>\n                  <span class=\"ols-t1-particle-dot d3\"><\/span>\n                <\/div>\n                <div class=\"ols-t1-visual-main\">Atoms,<br>Elements<br>&amp; Molecules<\/div>\n                <div class=\"ols-t1-visual-sub\">atoms, ions, molecules, compounds and formulae<\/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\">Atoms, Elements and Molecules<\/p>\n            <p class=\"ols-t1-card-desc\">Key definitions including atom, element, ion, molecule, compound, empirical formula and molecular formula.<\/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: Equations and Reaction Types -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/equations-and-reaction-types\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--equations\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Equations and tests<\/div>\n                <div class=\"ols-t1-equation-line\" aria-hidden=\"true\">A + B \u2192 C<\/div>\n                <div class=\"ols-t1-visual-main\">Equations<br>&amp; Reaction<br>Types<\/div>\n                <div class=\"ols-t1-visual-sub\">balanced, ionic and full equations<\/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\">Equations and Reaction Types<\/p>\n            <p class=\"ols-t1-card-desc\">Balanced equations, ionic equations, state symbols, acid reactions and precipitation reactions.<\/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: Mole Calculations -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/mole-calculations\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--moles\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Amount of substance<\/div>\n                <div class=\"ols-t1-mole-stack\" aria-hidden=\"true\">\n                  <span><\/span><span><\/span><span><\/span>\n                <\/div>\n                <div class=\"ols-t1-visual-main\">Mole<br>Calculations<\/div>\n                <div class=\"ols-t1-visual-sub\">moles, Avogadro constant, mass and reacting quantities<\/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\">Mole Calculations<\/p>\n            <p class=\"ols-t1-card-desc\">The mole, Avogadro constant, molar mass, reacting masses, percentage yield and atom economy.<\/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: Empirical and Molecular Formulae -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/empirical-and-molecular-formulae\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--formulae\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Formulae from data<\/div>\n                <div class=\"ols-t1-formula-box\" aria-hidden=\"true\">C<sub>2<\/sub>H<sub>6<\/sub>O<\/div>\n                <div class=\"ols-t1-visual-main\">Empirical<br>&amp; Molecular<br>Formulae<\/div>\n                <div class=\"ols-t1-visual-sub\">formulae from experimental data and mass values<\/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\">Empirical and Molecular Formulae<\/p>\n            <p class=\"ols-t1-card-desc\">Using experimental data, percentage composition and molar mass to calculate empirical and molecular formulae.<\/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: Calculations with Solutions and Gases -->\n        <a class=\"ols-t1-card ols-t1-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel-international\/topic-1-formulae-equations-and-amount-of-substance\/calculations-with-solutions-and-gases\/\">\n          <div class=\"ols-t1-card-img-wrap\">\n            <div class=\"ols-t1-visual ols-t1-visual--solutions\">\n              <div class=\"ols-t1-visual-panel\">\n                <div class=\"ols-t1-visual-kicker\">Solutions and gases<\/div>\n                <div class=\"ols-t1-solution-icon\" aria-hidden=\"true\"><\/div>\n                <div class=\"ols-t1-visual-main\">Solutions<br>&amp; Gases<\/div>\n                <div class=\"ols-t1-visual-sub\">concentration, gas volumes and pV = nRT<\/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\">Calculations with Solutions and Gases<\/p>\n            <p class=\"ols-t1-card-desc\">Concentration in mol dm<sup>-3<\/sup> and g dm<sup>-3<\/sup>, gas volumes, molar volume and the ideal gas equation.<\/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 Formulae, Equations and Amount of Substance &#8211; Edexcel International A Level Chemistry<\/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. Ideas from this topic are applied across all other units.<\/p>\n\n        <h3 class=\"ols-t1-spec-group-title\">Chemical Language and Formulae<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.1<\/div>\n            <div class=\"ols-t1-spec-text\">know the terms atom, element, ion, molecule, compound, empirical formula and molecular formula<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.4<\/div>\n            <div class=\"ols-t1-spec-text\">\n              understand relative atomic mass, relative molecular mass, relative formula mass, molar mass and parts per million.\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\">relative atomic mass based on the <sup>12<\/sup>C scale<\/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\">relative molecular mass and relative formula mass, including calculating these values from relative atomic masses<\/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\">molar mass as the mass per mole of a substance in g mol<sup>-1<\/sup><\/div>\n                <\/div>\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">iv<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">parts per million, ppm, including gases in the atmosphere<\/div>\n                <\/div>\n              <\/div>\n              <em>The term relative formula mass should be used for compounds with giant structures.<\/em>\n            <\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">The Mole and Core Calculations<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.2<\/div>\n            <div class=\"ols-t1-spec-text\">know that the mole, mol, is the unit for the amount of a substance and be able to perform calculations using the Avogadro constant, L, 6.02 &times; 10<sup>23<\/sup> mol<sup>-1<\/sup><\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.5<\/div>\n            <div class=\"ols-t1-spec-text\">calculate the concentration of a solution in mol dm<sup>-3<\/sup> and g dm<sup>-3<\/sup>. <em>Titration calculations are not required at this stage.<\/em><\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.7<\/div>\n            <div class=\"ols-t1-spec-text\">be able to use chemical equations to calculate reacting masses and vice versa, using the concepts of amount of substance and molar mass<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.8<\/div>\n            <div class=\"ols-t1-spec-text\">\n              be able to use chemical equations to calculate volumes of gases and vice versa.\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 concepts of amount of substance<\/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 molar volume of gases<\/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 expression <em>pV = nRT<\/em> for gases and volatile liquids<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.9<\/div>\n            <div class=\"ols-t1-spec-text\">\n              be able to calculate percentage yields and percentage atom economies, by mass, in laboratory and industrial processes, using chemical equations and experimental results.\n              <div class=\"ols-t1-spec-formula\">Atom economy = molar mass of the desired product &divide; sum of the molar masses of all products &times; 100%<\/div>\n            <\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">Equations, Formulae and Experimental Data<\/h3>\n        <div class=\"ols-t1-spec-rows\">\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.3<\/div>\n            <div class=\"ols-t1-spec-text\">write balanced full and ionic equations, including state symbols, for chemical reactions<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.6<\/div>\n            <div class=\"ols-t1-spec-text\">be able to use experimental data to calculate empirical and molecular formulae<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.10<\/div>\n            <div class=\"ols-t1-spec-text\">be able to determine a formula or confirm an equation by experiment, including evaluation of the data<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">1.12<\/div>\n            <div class=\"ols-t1-spec-text\">\n              be able to relate ionic and full equations, with state symbols, to observations from simple test-tube experiments.\n              <div class=\"ols-t1-spec-sub-list\">\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\">typical reactions of acids<\/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\">precipitation reactions<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n        <\/div>\n\n        <h3 class=\"ols-t1-spec-group-title\">Core Practical and Further Suggested Practicals<\/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\">1.11<\/div>\n            <div class=\"ols-t1-spec-text\"><strong>CORE PRACTICAL 1<\/strong><br>Measurement of the molar volume of a gas.<\/div>\n          <\/div>\n          <div class=\"ols-t1-spec-row\">\n            <div class=\"ols-t1-spec-code\">Practical<\/div>\n            <div class=\"ols-t1-spec-text\">\n              Further suggested practicals include preparing a salt and calculating percentage yield, determining a chemical formula by experiment, determining a chemical equation by experiment, and carrying out and interpreting simple test-tube reactions from 1.12.\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\">preparation of a salt and calculating percentage yield of product, including the preparation of a double salt, such as ammonium iron(II) sulfate from iron, ammonia and sulfuric acid<\/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\">determine a chemical formula by experiment, such as the formula of copper(II) oxide by reduction<\/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\">determine a chemical equation by experiment, such as the reaction between lithium and water, or the reaction between magnesium and an acid<\/div>\n                <\/div>\n                <div class=\"ols-t1-spec-sub-row\">\n                  <div class=\"ols-t1-spec-sub-code\">iv<\/div>\n                  <div class=\"ols-t1-spec-sub-text\">carry out and interpret the results of simple test-tube reactions, as outlined in 1.12<\/div>\n                <\/div>\n              <\/div>\n            <\/div>\n          <\/div>\n        <\/div>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n<\/div>\n\n","protected":false},"excerpt":{"rendered":"<p>Revision Notes \/ A Level Chemistry \/ Edexcel International \/ Topic 1 Formulae, Equations and Amount of Substance Edexcel International A Level Chemistry Topic 1Formulae, Equations&amp; Amount of Substance Topic 1 builds the calculation and chemical language foundation for A Level Chemistry. It covers atoms, elements, ions, molecules, compounds, empirical formulae, molecular formulae, balanced equations, [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":1786,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3998","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/3998","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=3998"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/3998\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/1786"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=3998"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}