{"id":12369,"date":"2026-09-30T19:40:13","date_gmt":"2026-09-30T18:40:13","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/"},"modified":"2026-09-30T19:40:13","modified_gmt":"2026-09-30T18:40:13","slug":"5-1-1-how-fast","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/","title":{"rendered":"5.1.1 How Fast?"},"content":{"rendered":"\n<div class=\"ols-ocr511-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>5.1.1 How Fast?<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/\">5.1.1 How Fast? Overview<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-equations-orders-and-the-rate-constant\/\">Rate Equations, Orders and the Rate Constant<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/techniques-for-measuring-rates\/\">Techniques for Measuring Rates<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/concentration-time-graphs-and-half-life\/\">Concentration\u2013Time Graphs and Half-Life<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-concentration-graphs-and-the-initial-rates-method\/\">Rate\u2013Concentration Graphs and the Initial-Rates Method<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/the-iodine-propanone-reaction\/\">The Iodine\u2013Propanone Reaction<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-determining-step-and-reaction-mechanisms\/\">Rate-Determining Step and Reaction Mechanisms<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/activation-energy-and-the-arrhenius-equation\/\">Activation Energy and the Arrhenius Equation<\/a>\n      <\/li>\n    <\/ul>\n  <\/div>\n\n  <div class=\"ols-topic-group\">\n    <h4>Other Sections<\/h4>\n\n    <ul class=\"ols-topic-list\">\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/3-2-2-reaction-rates\/\">3.2.2 Reaction Rates<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/3-2-3-chemical-equilibrium\/\">3.2.3 Chemical Equilibrium<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/3-2-1-enthalpy-changes\/\">3.2.1 Enthalpy Changes<\/a>\n      <\/li>\n      <li>\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/practical-activity-groups\/\">Practical Activity Groups<\/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 (!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    sidebar.querySelectorAll('a[data-ols-disabled-parent=\"1\"], a[aria-current]').forEach(function(a) {\r\n      a.removeAttribute('aria-current');\r\n      a.removeAttribute('tabindex');\r\n      a.removeAttribute('data-ols-disabled-parent');\r\n    });\r\n\r\n    links.forEach(function(a) {\r\n      try {\r\n        var href = a.getAttribute('href');\r\n        if (!href || href === '#' || href.charAt(0) === '#') return;\r\n        var linkPath = normalisePath(new URL(href, window.location.origin).pathname);\r\n        if (!linkPath) return;\r\n        if (currentPath === linkPath || currentPath.indexOf(linkPath + '\/') === 0) {\r\n          if (linkPath.length > matchedLength) {\r\n            matched = a;\r\n            matchedLength = linkPath.length;\r\n          }\r\n        }\r\n      } catch(e) {}\r\n    });\r\n\r\n    if (matched) {\r\n      var matchedLi = matched.closest('li');\r\n      var parentSub = matched.closest('.ols-subtopic-list');\r\n\r\n      if (parentSub) {\r\n        if (matchedLi) {\r\n          matchedLi.classList.add('active');\r\n          matched.setAttribute('aria-current', 'page');\r\n        }\r\n\r\n        var parentLi = parentSub.closest('li');\r\n        while (parentLi) {\r\n          parentLi.classList.add('parent-active', 'active-main');\r\n\r\n          var parentLink = parentLi.querySelector(':scope > a');\r\n          if (parentLink) {\r\n            parentLink.setAttribute('aria-current', 'true');\r\n            parentLink.setAttribute('tabindex', '-1');\r\n            parentLink.setAttribute('data-ols-disabled-parent', '1');\r\n          }\r\n\r\n          var higherSub = parentLi.parentElement.closest('.ols-subtopic-list');\r\n          parentLi = higherSub ? higherSub.closest('li') : null;\r\n        }\r\n      } else {\r\n        if (matchedLi) {\r\n          matchedLi.classList.add('parent-active', 'active-main');\r\n          matched.setAttribute('aria-current', 'page');\r\n          matched.setAttribute('tabindex', '-1');\r\n          matched.setAttribute('data-ols-disabled-parent', '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>\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-ocr511-page,\n    .ols-ocr511-page * { box-sizing: border-box; }\n\n    .ols-ocr511-page {\n      --ols-purple: #0a5740;\n      --ols-purple-2: #0f6e56;\n      --ols-accent: #2fbf8a;\n      --ols-soft-purple: #ecfdf5;\n      --ols-soft-cream: #fbf7f2;\n      --ols-border: rgba(59, 7, 100, 0.13);\n      --ols-shadow-soft: 0 10px 28px rgba(59, 7, 100, 0.09);\n      --ols-muted: #4f5f58;\n      font-family: \"Poppins\", Arial, sans-serif;\n      color: var(--ols-purple);\n      background: #ffffff;\n    }\n\n    .ols-ocr511-page a { color: inherit; text-decoration: none; }\n    .ols-ocr511-container { width: min(1180px, calc(100% - 40px)); margin: 0 auto; }\n\n    .ols-ocr511-breadcrumb-bar { padding: 16px 0 0; }\n    .ols-ocr511-breadcrumb { display: flex; flex-wrap: wrap; gap: 6px; font-size: 13px; color: var(--ols-muted); font-weight: 500; }\n    .ols-ocr511-breadcrumb a { color: var(--ols-muted); transition: color 0.2s ease; }\n    .ols-ocr511-breadcrumb a:hover { color: var(--ols-accent); }\n    .ols-ocr511-breadcrumb span { color: var(--ols-purple); font-weight: 700; }\n\n    .ols-ocr511-intro {\n      padding: 36px 0 72px;\n      background:\n        radial-gradient(circle at top center, rgba(47, 191, 138, 0.08), transparent 40%),\n        linear-gradient(180deg, #fbf7f2 0%, #ffffff 100%);\n    }\n    .ols-ocr511-intro-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }\n    .ols-ocr511-eyebrow {\n      display: inline-flex; align-items: center; gap: 9px; padding: 8px 16px; border-radius: 999px;\n      background: #ffffff; border: 1px solid rgba(47, 191, 138, 0.22); color: var(--ols-accent);\n      font-size: 13px; font-weight: 600; box-shadow: 0 6px 18px rgba(59, 7, 100, 0.06); margin-bottom: 20px;\n    }\n    .ols-ocr511-eyebrow::before { content: \"\"; width: 7px; height: 7px; border-radius: 50%; background: var(--ols-accent); box-shadow: 0 0 0 4px rgba(47, 191, 138, 0.14); }\n    .ols-ocr511-intro h1 { font-size: clamp(34px, 4.5vw, 64px); font-weight: 800; color: var(--ols-purple); letter-spacing: -0.045em; line-height: 1.08; margin: 0 0 10px; text-shadow: -9px 0 9px rgba(59, 7, 100, 0.08); }\n    .ols-ocr511-accent-bar { width: 72px; height: 4px; background: var(--ols-accent); border-radius: 999px; margin: 0 0 22px; }\n    .ols-ocr511-intro-lead { font-size: clamp(16px, 1.6vw, 19px); font-weight: 300; color: #0a4a36; line-height: 1.72; margin: 0; }\n\n    .ols-ocr511-info-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }\n    .ols-ocr511-info-card { background: #ffffff; border: 1px solid var(--ols-border); border-radius: 20px; padding: 20px 22px; box-shadow: var(--ols-shadow-soft); }\n    .ols-ocr511-info-card-label { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: var(--ols-muted); margin-bottom: 6px; }\n    .ols-ocr511-info-card-value { font-size: 22px; font-weight: 800; color: var(--ols-purple); letter-spacing: -0.03em; line-height: 1.1; }\n    .ols-ocr511-info-card-sub { font-size: 12px; font-weight: 400; color: var(--ols-muted); margin-top: 3px; }\n\n    .ols-ocr511-topics { padding: 72px 0 80px; background: #ffffff; }\n    .ols-ocr511-section-header { margin-bottom: 40px; }\n    .ols-ocr511-section-title { font-size: clamp(28px, 3vw, 44px); font-weight: 800; color: var(--ols-purple); letter-spacing: -0.04em; line-height: 1.1; margin: 0 0 10px; text-shadow: -9px 0 9px rgba(59, 7, 100, 0.08); }\n    .ols-ocr511-section-sub { font-size: 16px; font-weight: 300; color: var(--ols-muted); margin: 0; }\n    .ols-ocr511-cards-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 20px; }\n\n    .ols-ocr511-card {\n      display: flex; flex-direction: column; background: #ffffff; border: 1px solid var(--ols-border);\n      border-radius: 22px; overflow: hidden; box-shadow: var(--ols-shadow-soft); text-decoration: none;\n      color: var(--ols-purple); transition: transform 0.28s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.28s ease, border-color 0.28s ease; position: relative;\n    }\n    .ols-ocr511-card.ols-ocr511-card--available:hover { transform: translateY(-10px) scale(1.02); box-shadow: 0 28px 56px rgba(59, 7, 100, 0.16); border-color: rgba(47, 191, 138, 0.35); }\n    .ols-ocr511-card.ols-ocr511-card--available:hover .ols-ocr511-card-img-wrap::after { opacity: 1; }\n    .ols-ocr511-card-img-wrap { position: relative; width: 100%; aspect-ratio: 4 \/ 3; background: var(--ols-soft-purple); overflow: hidden; }\n    .ols-ocr511-card-img-wrap::after { content: \"\"; position: absolute; inset: 0; background: linear-gradient(180deg, transparent 40%, rgba(59, 7, 100, 0.18) 100%); opacity: 0; transition: opacity 0.28s ease; z-index: 1; }\n    .ols-ocr511-card-num { position: absolute; top: 12px; left: 12px; width: 32px; height: 32px; border-radius: 50%; background: var(--ols-purple); color: #ffffff; font-size: 13px; font-weight: 800; display: flex; align-items: center; justify-content: center; z-index: 3; box-shadow: 0 4px 12px rgba(59, 7, 100, 0.28); }\n    .ols-ocr511-card-status { position: absolute; top: 12px; right: 12px; padding: 4px 10px; border-radius: 999px; font-size: 10px; font-weight: 700; z-index: 3; }\n    .ols-ocr511-card-status--available { background: #eaf3de; color: #3B6D11; }\n    .ols-ocr511-card-body { padding: 18px 18px 22px; flex: 1; display: flex; flex-direction: column; gap: 6px; }\n    .ols-ocr511-card-title { font-size: 14px; font-weight: 700; color: var(--ols-purple); line-height: 1.35; margin: 0; }\n    .ols-ocr511-card-desc { font-size: 12px; font-weight: 300; color: var(--ols-muted); line-height: 1.6; margin: 0; }\n    .ols-ocr511-card-cta { display: inline-flex; align-items: center; gap: 5px; margin-top: 10px; font-size: 12px; font-weight: 700; color: var(--ols-accent); }\n    .ols-ocr511-card-cta svg { width: 14px; height: 14px; transition: transform 0.2s ease; }\n    .ols-ocr511-card--available:hover .ols-ocr511-card-cta svg { transform: translateX(3px); }\n\n    .ols-ocr511-visual { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; padding: 32px 24px 24px; overflow: hidden; }\n    .ols-ocr511-visual::before, .ols-ocr511-visual::after { content: \"\"; position: absolute; border-radius: 999px; opacity: 0.75; filter: blur(1px); }\n    .ols-ocr511-visual::before { width: 170px; height: 170px; left: -58px; bottom: -66px; background: rgba(255, 255, 255, 0.35); }\n    .ols-ocr511-visual::after { width: 118px; height: 118px; right: -42px; top: -34px; background: rgba(255, 255, 255, 0.28); }\n    .ols-ocr511-visual-panel { position: relative; z-index: 2; width: min(82%, 260px); min-height: 118px; border-radius: 24px; border: 1px solid rgba(255, 255, 255, 0.45); background: rgba(255, 255, 255, 0.76); box-shadow: 0 18px 38px rgba(59, 7, 100, 0.18); backdrop-filter: blur(10px); display: flex; flex-direction: column; align-items: center; justify-content: center; text-align: center; padding: 18px; }\n    .ols-ocr511-visual-kicker { display: inline-flex; align-items: center; justify-content: center; min-height: 25px; padding: 4px 10px; border-radius: 999px; background: rgba(59, 7, 100, 0.08); color: var(--ols-purple); font-size: 10px; font-weight: 800; text-transform: uppercase; letter-spacing: 0.08em; margin-bottom: 10px; }\n    .ols-ocr511-visual-main { font-size: clamp(23px, 3vw, 32px); font-weight: 800; color: var(--ols-purple); line-height: 1.05; letter-spacing: -0.05em; }\n    .ols-ocr511-config-line { display: inline-flex; gap: 7px; margin-top: 12px; flex-wrap: wrap; justify-content: center; }\n    .ols-ocr511-config-line span { display: inline-flex; min-width: 42px; justify-content: center; padding: 5px 8px; border-radius: 999px; background: #ffffff; border: 1px solid rgba(59, 7, 100, 0.16); font-size: 11px; font-weight: 800; color: var(--ols-purple); }\n\n    .ols-ocr511-visual--ionic { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #ecfdf5 0%, #6ee7b7 45%, #15803d 100%); }\n    .ols-ocr511-visual--covalent { background: radial-gradient(circle at 22% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fff7ed 0%, #fb923c 45%, #c2410c 100%); }\n    .ols-ocr511-visual--shapes { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #ecfeff 0%, #22d3ee 45%, #0e7490 100%); }\n    .ols-ocr511-visual--polarity { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fdf2f8 0%, #f472b6 45%, #be185d 100%); }\n    .ols-ocr511-visual--metallic { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f8fafc 0%, #94a3b8 45%, #334155 100%); }\n    .ols-ocr511-visual--giant { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #eefbf3 0%, #86efac 45%, #15803d 100%); }\n    .ols-ocr511-visual--molecular { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #eff6ff 0%, #60a5fa 45%, #1d4ed8 100%); }\n    .ols-ocr511-visual--forces { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fefce8 0%, #facc15 45%, #a16207 100%); }\n\n    .ols-ocr511-spec-section { padding: 72px 0 88px; background: radial-gradient(circle at top center, rgba(47, 191, 138, 0.07), transparent 38%), linear-gradient(180deg, #fbf7f2 0%, #ffffff 100%); }\n    .ols-ocr511-spec-wrap { background: #ffffff; border: 1px solid var(--ols-border); border-radius: 26px; padding: 36px; box-shadow: var(--ols-shadow-soft); }\n    .ols-ocr511-spec-pill { display: inline-flex; align-items: center; padding: 7px 14px; border-radius: 999px; background: var(--ols-soft-purple); border: 1px solid rgba(47, 191, 138, 0.22); color: var(--ols-accent); font-size: 12px; font-weight: 700; margin-bottom: 16px; }\n    .ols-ocr511-spec-heading { font-size: clamp(24px, 2.8vw, 36px); font-weight: 800; color: var(--ols-purple); letter-spacing: -0.035em; line-height: 1.12; margin: 0 0 6px; border-left: 5px solid var(--ols-accent); padding-left: 16px; }\n    .ols-ocr511-spec-intro-text { font-size: 16px; font-weight: 300; color: #2f4a3e; line-height: 1.8; margin: 14px 0 26px; }\n    .ols-ocr511-spec-group-title { font-size: 20px; font-weight: 800; color: var(--ols-purple); line-height: 1.2; margin: 30px 0 14px; letter-spacing: -0.025em; }\n    .ols-ocr511-spec-rows { display: flex; flex-direction: column; gap: 12px; }\n    .ols-ocr511-spec-row { display: flex; flex-wrap: nowrap; align-items: stretch; border-radius: 16px; overflow: hidden; box-shadow: 0 4px 12px rgba(0,0,0,0.05); }\n    .ols-ocr511-spec-row--light { background: #ffffff; border: 1px solid rgba(47, 191, 138, 0.18); }\n    .ols-ocr511-spec-row--mid { background: #ecfdf5; border: 1px solid rgba(47, 191, 138, 0.22); }\n    .ols-ocr511-spec-code { flex: 0 0 104px; color: #ffffff; font-size: 15px; font-weight: 800; display: flex; align-items: center; justify-content: center; padding: 18px 12px; background: #0a5740; }\n    .ols-ocr511-spec-code--mid { background: #0f6e56; }\n    .ols-ocr511-spec-text { flex: 1; padding: 16px 20px; font-size: 16px; font-weight: 300; line-height: 1.8; color: #2f4a3e; }\n    .ols-ocr511-spec-sub-list { display: flex; flex-direction: column; gap: 10px; margin-top: 12px; }\n    .ols-ocr511-spec-sub-row { display: flex; align-items: stretch; background: #ffffff; border: 1px solid rgba(47, 191, 138, 0.15); border-radius: 12px; overflow: hidden; }\n    .ols-ocr511-spec-sub-code { flex: 0 0 74px; background: #6ee7b7; color: #0a5740; font-size: 13px; font-weight: 800; display: flex; align-items: center; justify-content: center; padding: 12px 10px; }\n    .ols-ocr511-spec-sub-text { flex: 1; padding: 12px 16px; font-size: 15px; font-weight: 300; line-height: 1.8; color: #4b3b58; }\n\n    @media (max-width: 1100px) { .ols-ocr511-cards-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); } }\n    @media (max-width: 860px) { .ols-ocr511-intro-inner { grid-template-columns: 1fr; gap: 40px; } }\n    @media (max-width: 640px) {\n      .ols-ocr511-intro { padding: 24px 0 52px; }\n      .ols-ocr511-topics { padding: 52px 0 58px; }\n      .ols-ocr511-cards-grid { grid-template-columns: 1fr; gap: 14px; }\n      .ols-ocr511-spec-section { padding: 52px 0 64px; }\n      .ols-ocr511-spec-wrap { padding: 24px 18px; border-radius: 20px; }\n      .ols-ocr511-info-grid { grid-template-columns: 1fr 1fr; }\n      .ols-ocr511-spec-row { flex-direction: column; }\n      .ols-ocr511-spec-code { flex: 0 0 auto; min-height: 34px; }\n    }\n      .ols-ocr511-visual--ox { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fff7ed 0%, #fb923c 45%, #c2410c 100%); }\n    .ols-ocr511-visual--et { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #eef2ff 0%, #818cf8 45%, #3730a3 100%); }\n    .ols-ocr511-visual--dp { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fdf2f8 0%, #f472b6 45%, #9d174d 100%); }\n    .ols-ocr511-visual--rc { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f0fdf4 0%, #4ade80 45%, #15803d 100%); }\n    .ols-ocr511-visual--tr { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f0f9ff 0%, #38bdf8 45%, #0369a1 100%); }\n    .ols-ocr511-visual--re { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fff1f2 0%, #fb7185 45%, #be123c 100%); }\n    .ols-ocr511-visual--oh { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f5f3ff 0%, #a78bfa 45%, #6d28d9 100%); }\n    .ols-ocr511-visual--so { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #ecfeff 0%, #22d3ee 45%, #0e7490 100%); }\n    .ols-ocr511-visual--ts { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fffbeb 0%, #fbbf24 45%, #b45309 100%); }\n    .ols-ocr511-visual--ti { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f0fdfa 0%, #2dd4bf 45%, #0f766e 100%); }\n    .ols-ocr511-visual--tc { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f8fafc 0%, #94a3b8 45%, #334155 100%); }\n    .ols-ocr511-visual--ht { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #ecfdf5 0%, #34d399 45%, #047857 100%); }\n    .ols-ocr511-visual--ho { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fefce8 0%, #facc15 45%, #a16207 100%); }\n    .ols-ocr511-visual--cd { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f0fdf4 0%, #86efac 45%, #166534 100%); }\n    .ols-ocr511-visual--hi { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fdf4ff 0%, #d8b4fe 45%, #7e22ce 100%); }\n    .ols-ocr511-visual--ca { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #fff7ed 0%, #fb923c 45%, #9a3412 100%); }\n    .ols-ocr511-visual--de { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #eef2ff 0%, #818cf8 45%, #3730a3 100%); }\n    .ols-ocr511-visual--lc { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #ecfeff 0%, #22d3ee 45%, #0e7490 100%); }\n    .ols-ocr511-visual--ei { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f5f3ff 0%, #a78bfa 45%, #5b21b6 100%); }\n    .ols-ocr511-visual--kc { background: radial-gradient(circle at 24% 18%, rgba(255,255,255,0.46), transparent 24%), linear-gradient(135deg, #f0fdf4 0%, #4ade80 45%, #166534 100%); }\n  <\/style>\n\n  <!-- BREADCRUMB BAR -->\n  <div class=\"ols-ocr511-breadcrumb-bar\">\n    <div class=\"ols-ocr511-container\">\n      <nav class=\"ols-ocr511-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\/ocr-a\/\">OCR<\/a> \/\n          <span>5.1.1 How Fast?<\/span>\n        <\/nav>\n    <\/div>\n  <\/div>\n\n  <!-- INTRO -->\n  <section class=\"ols-ocr511-intro\">\n    <div class=\"ols-ocr511-container\">\n      <div class=\"ols-ocr511-intro-inner\">\n        <div>\n          <div class=\"ols-ocr511-eyebrow\">OCR A Level Chemistry A &#8211; Module 5 Physical Chemistry and Transition Elements<\/div>\n          <h1>5.1.1<br>How Fast?<\/h1>\n          <div class=\"ols-ocr511-accent-bar\"><\/div>\n          <p class=\"ols-ocr511-intro-lead\">Section 5.1.1 covers rate, order, overall order, the rate constant, half-life and the rate-determining step; deducing orders and rate equations from experimental data; calculating k and its units; concentration\u2013time graphs including the constant half-life of a first-order reaction and k = ln 2 \/ t\u00bd; rate\u2013concentration graphs; the initial-rates and continuous monitoring techniques including colorimetry; predicting mechanisms from rate equations; and the Arrhenius equation with the graphical determination of E\u2090 and A. PAG 10 supplies the rate data.<\/p>\n        <\/div>\n        <div class=\"ols-ocr511-info-grid\">\n          <div class=\"ols-ocr511-info-card\"><div class=\"ols-ocr511-info-card-label\">Exam Paper<\/div><div class=\"ols-ocr511-info-card-value\">Paper 1 &amp; 3<\/div><div class=\"ols-ocr511-info-card-sub\">H432\/01 and H432\/03<\/div><\/div>\n          <div class=\"ols-ocr511-info-card\"><div class=\"ols-ocr511-info-card-label\">Learning Outcomes<\/div><div class=\"ols-ocr511-info-card-value\">5.1.1 (a) &#8211; (k)<\/div><div class=\"ols-ocr511-info-card-sub\">11 learning outcomes<\/div><\/div>\n          <div class=\"ols-ocr511-info-card\"><div class=\"ols-ocr511-info-card-label\">Topic Parts<\/div><div class=\"ols-ocr511-info-card-value\">7 pages<\/div><div class=\"ols-ocr511-info-card-sub\">Revision notes available<\/div><\/div>\n          <div class=\"ols-ocr511-info-card\"><div class=\"ols-ocr511-info-card-label\">Exam Board<\/div><div class=\"ols-ocr511-info-card-value\">OCR A<\/div><div class=\"ols-ocr511-info-card-sub\">H432 (2015 onwards)<\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- TOPIC CARDS -->\n  <section class=\"ols-ocr511-topics\">\n    <div class=\"ols-ocr511-container\">\n      <div class=\"ols-ocr511-section-header\">\n        <h2 class=\"ols-ocr511-section-title\">Revision Notes<\/h2>\n        <p class=\"ols-ocr511-section-sub\">Work through 5.1.1 How Fast? in a structured sequence.<\/p>\n      <\/div>\n      <div class=\"ols-ocr511-cards-grid\">\n\n        <!-- Card 1: Rate Equations, Orders and the Rate Constant -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-equations-orders-and-the-rate-constant\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--ox\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">rate = k[A]\u1d50[B]\u207f<\/div>\n                <div class=\"ols-ocr511-visual-main\">Rate<br>Equations<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>orders, k, units of k<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">1<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">Rate Equations, Orders and the Rate Constant<\/p>\n            <p class=\"ols-ocr511-card-desc\">Rate equations: orders of reaction, the rate constant k, overall order and working out the units of k.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 2: Techniques for Measuring Rates -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/techniques-for-measuring-rates\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--tc\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">Choose a method<\/div>\n                <div class=\"ols-ocr511-visual-main\">Measuring<br>Rates<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>quench, colorimeter, syringe, clock<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">2<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">Techniques for Measuring Rates<\/p>\n            <p class=\"ols-ocr511-card-desc\">Measuring rates: titration, colorimetry, mass and gas-volume methods, continuous monitoring and the initial-rates method with clock reactions.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 3: Concentration\u2013Time Graphs and Half-Life -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/concentration-time-graphs-and-half-life\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--tr\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">Curves and t\u00bd<\/div>\n                <div class=\"ols-ocr511-visual-main\">Concentration\u2013<br>Time Graphs<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>order from shape, constant half-life<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">3<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">Concentration\u2013Time Graphs and Half-Life<\/p>\n            <p class=\"ols-ocr511-card-desc\">Concentration\u2013time graphs: deducing order from the shape, tangents and rates, half-life and first-order reactions, k from the half-life.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 4: Rate\u2013Concentration Graphs and the Initial-Rates Method -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-concentration-graphs-and-the-initial-rates-method\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--ca\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">Compare the runs<\/div>\n                <div class=\"ols-ocr511-visual-main\">Initial-Rates<br>Method<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>double [A], what happens to rate?<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">4<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">Rate\u2013Concentration Graphs and the Initial-Rates Method<\/p>\n            <p class=\"ols-ocr511-card-desc\">The initial-rates method: rate\u2013concentration graphs, deducing orders from tables of data, writing the rate equation and calculating k.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 5: The Iodine\u2013Propanone Reaction -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/the-iodine-propanone-reaction\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--de\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">Worked example<\/div>\n                <div class=\"ols-ocr511-visual-main\">Iodine and<br>Propanone<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>zero order in I\u2082, rate = k[propanone][H\u207a]<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">5<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">The Iodine\u2013Propanone Reaction<\/p>\n            <p class=\"ols-ocr511-card-desc\">The iodine\u2013propanone reaction: collecting rate data, the orders with respect to iodine, propanone and H\u207a, and deducing the mechanism.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 6: Rate-Determining Step and Reaction Mechanisms -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-determining-step-and-reaction-mechanisms\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--lc\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">The slow step<\/div>\n                <div class=\"ols-ocr511-visual-main\">Rate-Determining<br>Step<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>mechanisms, intermediates, S\u20991 and S\u20992<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">6<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">Rate-Determining Step and Reaction Mechanisms<\/p>\n            <p class=\"ols-ocr511-card-desc\">The rate-determining step: rate equations from mechanisms, mechanisms from rate equations, intermediates, and S\u20991\/S\u20992 evidence from haloalkanes hydrolysis.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n        <!-- Card 7: Activation Energy and the Arrhenius Equation -->\n        <a class=\"ols-ocr511-card ols-ocr511-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/activation-energy-and-the-arrhenius-equation\/\">\n          <div class=\"ols-ocr511-card-img-wrap\">\n            <div class=\"ols-ocr511-visual ols-ocr511-visual--ei\">\n              <div class=\"ols-ocr511-visual-panel\">\n                <div class=\"ols-ocr511-visual-kicker\">k = Ae^(\u2212E\u2090\/RT)<\/div>\n                <div class=\"ols-ocr511-visual-main\">Arrhenius<br>Equation<\/div>\n                <div class=\"ols-ocr511-config-line\" aria-hidden=\"true\"><span>ln k against 1\/T, gradient = \u2212E\u2090\/R<\/span><\/div>\n              <\/div>\n            <\/div>\n            <div class=\"ols-ocr511-card-num\">7<\/div>\n            <span class=\"ols-ocr511-card-status ols-ocr511-card-status--available\">Available<\/span>\n          <\/div>\n          <div class=\"ols-ocr511-card-body\">\n            <p class=\"ols-ocr511-card-title\">Activation Energy and the Arrhenius Equation<\/p>\n            <p class=\"ols-ocr511-card-desc\">The Arrhenius equation: temperature and the rate constant, ln k against 1\/T graphs and finding the activation energy from the gradient.<\/p>\n            <span class=\"ols-ocr511-card-cta\">Start revising<svg viewBox=\"0 0 16 16\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M3 8h10M9 4l4 4-4 4\"><\/path><\/svg><\/span>\n          <\/div>\n        <\/a>\n\n      <\/div>\n    <\/div>\n  <\/section>\n\n  <!-- SPECIFICATION -->\n  <section class=\"ols-ocr511-spec-section\">\n    <div class=\"ols-ocr511-container\">\n      <div class=\"ols-ocr511-spec-wrap\">\n        <div class=\"ols-ocr511-spec-pill\">Specification Coverage<\/div>\n        <h2 class=\"ols-ocr511-spec-heading\">5.1.1 How Fast? &#8211; OCR A Level Chemistry A<\/h2>\n        <p class=\"ols-ocr511-spec-intro-text\">The following OCR A learning outcomes state what candidates should be able to do. Wording is taken from the OCR A Level Chemistry A (H432) specification.<\/p>\n        <h3 class=\"ols-ocr511-spec-group-title\">5.1.1 Orders, rate equations and rate constants<\/h3>\n        <div class=\"ols-ocr511-spec-rows\">\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--light\"><div class=\"ols-ocr511-spec-code\">5.1.1(a)<\/div><div class=\"ols-ocr511-spec-text\"><div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">i<\/div><div class=\"ols-ocr511-spec-sub-text\">explanation and use of the term rate of reaction<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">ii<\/div><div class=\"ols-ocr511-spec-sub-text\">explanation and use of the term order<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">iii<\/div><div class=\"ols-ocr511-spec-sub-text\">explanation and use of the term overall order<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">iv<\/div><div class=\"ols-ocr511-spec-sub-text\">explanation and use of the term rate constant<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">v<\/div><div class=\"ols-ocr511-spec-sub-text\">explanation and use of the term half-life<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">vi<\/div><div class=\"ols-ocr511-spec-sub-text\">explanation and use of the term rate-determining step<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--mid\"><div class=\"ols-ocr511-spec-code ols-ocr511-spec-code--mid\">5.1.1(b)<\/div><div class=\"ols-ocr511-spec-text\"><div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(i)<\/div><div class=\"ols-ocr511-spec-sub-text\">deduction of orders from experimental data<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(ii)<\/div><div class=\"ols-ocr511-spec-sub-text\">deduction of a rate equation from orders of the form: rate = k[A]\u1d50[B]\u207f, where m and n are 0, 1 or 2<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--light\"><div class=\"ols-ocr511-spec-code\">5.1.1(c)<\/div><div class=\"ols-ocr511-spec-text\"><div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">i<\/div><div class=\"ols-ocr511-spec-sub-text\">calculation of the rate constant, k, and related quantities, from a rate equation<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">ii<\/div><div class=\"ols-ocr511-spec-sub-text\">determination of the units of the rate constant, k, from a rate equation<\/div><\/div><\/div><\/div><\/div>\n        <\/div>\n\n        <h3 class=\"ols-ocr511-spec-group-title\">5.1.1 Concentration\u2013time and rate\u2013concentration graphs, techniques<\/h3>\n        <div class=\"ols-ocr511-spec-rows\">\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--mid\"><div class=\"ols-ocr511-spec-code ols-ocr511-spec-code--mid\">5.1.1(d)<\/div><div class=\"ols-ocr511-spec-text\">from a concentration\u2013time graph:<div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(i)<\/div><div class=\"ols-ocr511-spec-sub-text\">deduction of the order (0 or 1) with respect to a reactant from the shape of the graph<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(ii)<\/div><div class=\"ols-ocr511-spec-sub-text\">calculation of reaction rates from the measurement of gradients (see also 3.2.2 b)<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--light\"><div class=\"ols-ocr511-spec-code\">5.1.1(e)<\/div><div class=\"ols-ocr511-spec-text\">from a concentration\u2013time graph of a first order reaction, measurement of constant half-life, t\u00bd<\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--mid\"><div class=\"ols-ocr511-spec-code ols-ocr511-spec-code--mid\">5.1.1(f)<\/div><div class=\"ols-ocr511-spec-text\">for a first order reaction, determination of the rate constant, k, from the constant half-life, t\u00bd, using the relationship: k = ln 2\/t\u00bd<\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--light\"><div class=\"ols-ocr511-spec-code\">5.1.1(g)<\/div><div class=\"ols-ocr511-spec-text\">from a rate\u2013concentration graph:<div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(i)<\/div><div class=\"ols-ocr511-spec-sub-text\">deduction of the order (0, 1 or 2) with respect to a reactant from the shape of the graph<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(ii)<\/div><div class=\"ols-ocr511-spec-sub-text\">determination of rate constant for a first order reaction from the gradient<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--mid\"><div class=\"ols-ocr511-spec-code ols-ocr511-spec-code--mid\">5.1.1(h)<\/div><div class=\"ols-ocr511-spec-text\"><div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">i<\/div><div class=\"ols-ocr511-spec-sub-text\">the techniques and procedures used to investigate reaction rates by the initial rates method (see also 3.2.2 e)<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">ii<\/div><div class=\"ols-ocr511-spec-sub-text\">the techniques and procedures used to investigate reaction rates by continuous monitoring, including use of colorimetry (see also 3.2.2 e)<\/div><\/div><\/div><\/div><\/div>\n        <\/div>\n\n        <h3 class=\"ols-ocr511-spec-group-title\">5.1.1 Rate-determining step and the effect of temperature<\/h3>\n        <div class=\"ols-ocr511-spec-rows\">\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--light\"><div class=\"ols-ocr511-spec-code\">5.1.1(i)<\/div><div class=\"ols-ocr511-spec-text\"><div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(i)<\/div><div class=\"ols-ocr511-spec-sub-text\">for a multi-step reaction, prediction of a rate equation that is consistent with the rate-determining step<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(ii)<\/div><div class=\"ols-ocr511-spec-sub-text\">for a multi-step reaction, prediction of possible steps in a reaction mechanism from the rate equation and the balanced equation for the overall reaction<\/div><\/div><\/div><\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--mid\"><div class=\"ols-ocr511-spec-code ols-ocr511-spec-code--mid\">5.1.1(j)<\/div><div class=\"ols-ocr511-spec-text\">a qualitative explanation of the effect of temperature change on the rate of a reaction and hence the rate constant (see 3.2.2 f\u2013g)<\/div><\/div>\n          <div class=\"ols-ocr511-spec-row ols-ocr511-spec-row--light\"><div class=\"ols-ocr511-spec-code\">5.1.1(k)<\/div><div class=\"ols-ocr511-spec-text\"><div class=\"ols-ocr511-spec-sub-list\"><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(i)<\/div><div class=\"ols-ocr511-spec-sub-text\">the exponential relationship between the rate constant, k and temperature, T given by the Arrhenius equation, k = Ae^(\u2013E\u2090\/RT)<\/div><\/div><div class=\"ols-ocr511-spec-sub-row\"><div class=\"ols-ocr511-spec-sub-code\">(ii)<\/div><div class=\"ols-ocr511-spec-sub-text\">determination of E\u2090 and A graphically using: ln k = \u2013E\u2090\/RT + ln A derived from the Arrhenius equation<\/div><\/div><\/div><\/div><\/div>\n        <\/div>\n      <\/div>\n    <\/div>\n  <\/section>\n  <script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@graph\": [\n    {\n      \"@type\": \"CollectionPage\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/#webpage\",\n      \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/\",\n      \"name\": \"5.1.1 How Fast? | OCR A A Level Chemistry | Online Learning System\",\n      \"description\": \"OCR A A Level Chemistry 5.1.1 How Fast? revision notes: rate equations, orders and the rate constant, techniques for measuring rates, concentration\u2013time graphs and half-life, rate\u2013concentration graphs and the initial-rates method, the iodine\u2013propanone reaction, rate-determining step and reaction mechanisms, activation energy and the arrhenius equation.\",\n      \"isPartOf\": {\n        \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/#website\"\n      },\n      \"breadcrumb\": {\n        \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/#breadcrumb\"\n      },\n      \"inLanguage\": \"en-GB\"\n    },\n    {\n      \"@type\": \"BreadcrumbList\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/#breadcrumb\",\n      \"itemListElement\": [\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 1,\n          \"name\": \"Revision Notes\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 2,\n          \"name\": \"A Level Chemistry\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 3,\n          \"name\": \"OCR\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/\"\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 4,\n          \"name\": \"5.1.1 How Fast?\",\n          \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/\"\n        }\n      ]\n    },\n    {\n      \"@type\": \"ItemList\",\n      \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/#topics\",\n      \"name\": \"5.1.1 How Fast? revision notes\",\n      \"itemListElement\": [\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 1,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"Rate Equations, Orders and the Rate Constant\",\n            \"description\": \"OCR A A Level Chemistry revision notes on rate equations: orders of reaction, the rate constant k, overall order and working out the units of k.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-equations-orders-and-the-rate-constant\/\"\n          }\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 2,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"Techniques for Measuring Rates\",\n            \"description\": \"OCR A A Level Chemistry revision notes on measuring rates: titration, colorimetry, mass and gas-volume methods, continuous monitoring and the initial-rates method with clock reactions.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/techniques-for-measuring-rates\/\"\n          }\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 3,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"Concentration\u2013Time Graphs and Half-Life\",\n            \"description\": \"OCR A A Level Chemistry revision notes on concentration\u2013time graphs: deducing order from the shape, tangents and rates, half-life and first-order reactions, k from the half-life.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/concentration-time-graphs-and-half-life\/\"\n          }\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 4,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"Rate\u2013Concentration Graphs and the Initial-Rates Method\",\n            \"description\": \"OCR A A Level Chemistry revision notes on the initial-rates method: rate\u2013concentration graphs, deducing orders from tables of data, writing the rate equation and calculating k.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-concentration-graphs-and-the-initial-rates-method\/\"\n          }\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 5,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"The Iodine\u2013Propanone Reaction\",\n            \"description\": \"OCR A A Level Chemistry revision notes on the iodine\u2013propanone reaction: collecting rate data, the orders with respect to iodine, propanone and H\u207a, and deducing the mechanism.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/the-iodine-propanone-reaction\/\"\n          }\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 6,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"Rate-Determining Step and Reaction Mechanisms\",\n            \"description\": \"OCR A A Level Chemistry revision notes on the rate-determining step: rate equations from mechanisms, mechanisms from rate equations, intermediates, and S\u20991\/S\u20992 evidence from haloalkanes hydrolysis.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/rate-determining-step-and-reaction-mechanisms\/\"\n          }\n        },\n        {\n          \"@type\": \"ListItem\",\n          \"position\": 7,\n          \"item\": {\n            \"@type\": \"Course\",\n            \"name\": \"Activation Energy and the Arrhenius Equation\",\n            \"description\": \"OCR A A Level Chemistry revision notes on the Arrhenius equation: temperature and the rate constant, ln k against 1\/T graphs and finding the activation energy from the gradient.\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/ocr-a\/5-1-1-how-fast\/activation-energy-and-the-arrhenius-equation\/\"\n          }\n        }\n      ]\n    }\n  ]\n}\n<\/script>\n\n<\/div>\n\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Revision Notes \/ A Level Chemistry \/ OCR \/ 5.1.1 How Fast? OCR A Level Chemistry A &#8211; Module 5 Physical Chemistry and Transition Elements 5.1.1How Fast? Section 5.1.1 covers rate, order, overall order, the rate constant, half-life and the rate-determining step; deducing orders and rate equations from experimental data; calculating k and its units; [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":7117,"menu_order":12,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-12369","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/12369","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=12369"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/12369\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/7117"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=12369"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}