{"id":4684,"date":"2026-06-01T12:06:08","date_gmt":"2026-06-01T11:06:08","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/"},"modified":"2026-06-28T05:51:38","modified_gmt":"2026-06-28T04:51:38","slug":"mole-calculations","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/","title":{"rendered":"Mole Calculations"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-mole-calculations-landing-page\">\n  <style>\n    .ols-revision-page {\n      --navy: #1C244B;\n      --blue: #2563eb;\n      --soft-blue: #eef4ff;\n      --soft-red: #fff7f7;\n      --soft-purple: #f7f0ff;\n      --soft-green: #f0f7f1;\n      --soft-orange: #fff7ed;\n      --gold: #c9973a;\n      --grey-text: #667085;\n      --body-text: #1f2937;\n      --border: rgba(28, 36, 75, 0.14);\n      --shadow: 0 18px 45px rgba(28, 36, 75, 0.10);\n      --inner-shadow: 0 10px 26px rgba(28, 36, 75, 0.08);\n      font-family: Poppins, Arial, sans-serif;\n      color: var(--navy);\n      background: #ffffff;\n    }\n\n    .ols-revision-page * { box-sizing: border-box; }\n\n    .ols-main {\n      min-width: 0;\n      max-width: 970px;\n    }\n\n    .ols-breadcrumbs {\n      display: flex;\n      flex-wrap: wrap;\n      gap: 8px;\n      margin: 10px 0 22px;\n      font-size: 15px;\n      color: var(--grey-text);\n    }\n\n    .ols-breadcrumbs a,\n    .ols-breadcrumbs span {\n      color: var(--grey-text);\n      text-decoration: none;\n      font-weight: 600;\n    }\n\n    .ols-breadcrumbs a:hover {\n      color: var(--blue);\n      text-decoration: underline;\n      text-underline-offset: 3px;\n    }\n\n    .ols-title-card,\n    .ols-note-card,\n    .ols-related-card,\n    .ols-attribution-card {\n      background: #ffffff;\n      border: 1px solid var(--border);\n      border-radius: 28px;\n      box-shadow: var(--shadow);\n      padding: 34px;\n      margin-bottom: 24px;\n      overflow: hidden;\n    }\n\n    .ols-title-card {\n      background: linear-gradient(135deg, #ffffff 0%, #f8fbff 100%);\n    }\n\n    .ols-title-card h1 {\n      margin: 0 0 18px;\n      font-size: clamp(36px, 5vw, 58px);\n      line-height: 1.08;\n      font-weight: 800;\n      letter-spacing: -0.04em;\n      color: #111827;\n    }\n\n    .ols-page-intro {\n      font-size: 19px;\n      line-height: 1.7;\n      font-weight: 300;\n      color: var(--body-text);\n      margin: 0 0 22px;\n    }\n\n    .ols-badges {\n      display: flex;\n      flex-wrap: wrap;\n      gap: 12px;\n      margin-bottom: 22px;\n    }\n\n    .ols-badge {\n      display: inline-flex;\n      align-items: center;\n      padding: 9px 14px;\n      border-radius: 999px;\n      background: #ffffff;\n      border: 1px solid var(--border);\n      font-size: 15px;\n      font-weight: 600;\n      color: var(--navy);\n    }\n\n    .ols-author {\n      display: flex;\n      align-items: center;\n      gap: 20px;\n      padding: 28px;\n      border-radius: 28px;\n      background: linear-gradient(135deg, #ffffff 0%, #f8fbff 100%);\n      border: 1px solid rgba(28,36,75,0.12);\n      box-shadow: 0 18px 45px rgba(28,36,75,0.10);\n      margin-top: 22px;\n    }\n\n    .ols-author-avatar-img {\n      width: 92px;\n      height: 92px;\n      border-radius: 50%;\n      object-fit: cover;\n      object-position: center;\n      flex-shrink: 0;\n      border: 4px solid #ffffff;\n      box-shadow: 0 14px 32px rgba(28,36,75,0.18), 0 0 0 1px rgba(28,36,75,0.10);\n      transition: transform 0.25s ease, box-shadow 0.25s ease;\n    }\n\n    .ols-author:hover .ols-author-avatar-img {\n      transform: scale(1.04);\n      box-shadow: 0 20px 42px rgba(28,36,75,0.22), 0 0 0 1px rgba(28,36,75,0.10);\n    }\n\n    .ols-author-content { min-width: 0; }\n\n    .ols-author-title {\n      margin: 0 0 4px;\n      font-size: clamp(24px,3vw,34px);\n      line-height: 1.15;\n      font-weight: 700;\n      color: var(--navy);\n      letter-spacing: -0.03em;\n    }\n\n    .ols-author-description {\n      margin: 0;\n      font-size: 17px;\n      line-height: 1.7;\n      font-weight: 300;\n      color: var(--grey-text);\n    }\n\n    .ols-linkedin-pill {\n      display: inline-flex;\n      align-items: center;\n      justify-content: center;\n      gap: 10px;\n      margin-top: 16px;\n      padding: 11px 18px;\n      border-radius: 999px;\n      background: linear-gradient(135deg,#0A66C2,#004182);\n      color: #ffffff;\n      text-decoration: none;\n      font-size: 14px;\n      line-height: 1;\n      font-weight: 700;\n      letter-spacing: 0.01em;\n      box-shadow: 0 10px 22px rgba(10,102,194,0.24);\n      position: relative;\n      overflow: hidden;\n      transition: transform 0.22s ease, box-shadow 0.22s ease;\n    }\n\n    .ols-linkedin-pill::before {\n      content: \"\";\n      position: absolute;\n      top: 0;\n      left: -120%;\n      width: 100%;\n      height: 100%;\n      background: linear-gradient(120deg, rgba(255,255,255,0) 0%, rgba(255,255,255,0.28) 50%, rgba(255,255,255,0) 100%);\n      transition: left 0.7s ease;\n    }\n\n    .ols-linkedin-pill:hover {\n      transform: translateY(-3px) scale(1.03);\n      box-shadow: 0 16px 34px rgba(10,102,194,0.34), 0 0 0 6px rgba(10,102,194,0.10);\n      color: #ffffff;\n    }\n\n    .ols-linkedin-pill:hover::before { left: 120%; }\n\n    .ols-linkedin-icon {\n      width: 18px;\n      height: 18px;\n      display: block;\n      flex-shrink: 0;\n    }\n\n    .ols-note-card.soft { background: linear-gradient(135deg, #ffffff 0%, var(--soft-red) 100%); }\n    .ols-note-card.purple { background: linear-gradient(135deg, #ffffff 0%, var(--soft-purple) 100%); }\n\n    .ols-note-title {\n      display: flex;\n      align-items: center;\n      gap: 14px;\n      margin-bottom: 20px;\n    }\n\n    .ols-note-icon {\n      width: 52px;\n      height: 52px;\n      border-radius: 16px;\n      background: var(--navy);\n      color: #ffffff;\n      display: grid;\n      place-items: center;\n      font-size: 24px;\n      font-weight: 800;\n      flex-shrink: 0;\n    }\n\n    .ols-note-title h2,\n    .ols-related-card h2 {\n      margin: 0;\n      font-size: clamp(28px, 3.5vw, 42px);\n      line-height: 1.15;\n      font-weight: 800;\n      color: #111827;\n      letter-spacing: -0.03em;\n    }\n\n    .ols-related-card h2 { margin-bottom: 14px; }\n\n    .ols-note-card p,\n    .ols-note-card li,\n    .ols-related-card p,\n    .ols-attribution-card p {\n      font-size: clamp(15px, 1.3vw, 18px);\n      line-height: 1.65;\n      font-weight: 300;\n      color: var(--body-text);\n    }\n\n    .ols-note-card strong,\n    .ols-related-card strong,\n    .ols-attribution-card strong {\n      font-weight: 700;\n      color: var(--navy);\n    }\n\n    .ols-key-box {\n      margin-top: 20px;\n      background: var(--soft-green);\n      border: 1px solid rgba(63, 143, 70, 0.25);\n      border-radius: 20px;\n      padding: 18px 20px;\n    }\n\n    .ols-key-box p {\n      margin: 0;\n      font-weight: 400;\n      color: var(--navy);\n    }\n\n    .ols-mole-grid {\n      display: grid;\n      grid-template-columns: repeat(2, minmax(0, 1fr));\n      gap: 18px;\n      margin-top: 26px;\n    }\n\n    .ols-mole-card {\n      position: relative;\n      display: grid;\n      grid-template-rows: auto 1fr auto;\n      min-height: 285px;\n      padding: 24px;\n      border-radius: 24px;\n      border: 1px solid rgba(28, 36, 75, 0.13);\n      background:\n        radial-gradient(circle at top right, rgba(37, 99, 235, 0.13), transparent 34%),\n        linear-gradient(135deg, #ffffff 0%, #f8fbff 100%);\n      color: var(--navy);\n      text-decoration: none;\n      overflow: hidden;\n      box-shadow: var(--inner-shadow);\n      transition: transform 0.24s ease, box-shadow 0.24s ease, border-color 0.24s ease, background 0.24s ease;\n    }\n\n    .ols-mole-card:hover {\n      transform: translateY(-6px);\n      border-color: rgba(37, 99, 235, 0.28);\n      box-shadow: 0 24px 52px rgba(28, 36, 75, 0.15);\n      color: var(--navy);\n    }\n\n    .ols-mole-card::before {\n      content: \"\";\n      position: absolute;\n      top: -60px;\n      right: -60px;\n      width: 145px;\n      height: 145px;\n      border-radius: 50%;\n      background: rgba(37, 99, 235, 0.08);\n      transition: transform 0.28s ease, background 0.28s ease;\n    }\n\n    .ols-mole-card:hover::before {\n      transform: scale(1.22);\n      background: rgba(37, 99, 235, 0.13);\n    }\n\n    .ols-mole-visual {\n      position: relative;\n      z-index: 1;\n      min-height: 94px;\n      display: flex;\n      align-items: center;\n      justify-content: center;\n      margin-bottom: 18px;\n    }\n\n    .ols-mole-icon {\n      position: relative;\n      width: 148px;\n      height: 94px;\n    }\n\n    .ols-mole-line,\n    .ols-mole-circle,\n    .ols-mole-dot,\n    .ols-mole-label,\n    .ols-mole-arrow,\n    .ols-mole-box,\n    .ols-mole-flask,\n    .ols-mole-tick,\n    .ols-mole-scale,\n    .ols-mole-beam,\n    .ols-mole-pan,\n    .ols-mole-stem {\n      position: absolute;\n      display: block;\n    }\n\n    .ols-mole-label {\n      color: var(--navy);\n      font-weight: 800;\n      font-size: 13px;\n      line-height: 1;\n      white-space: nowrap;\n    }\n\n    .ols-mole-mass .ols-mole-beam {\n      left: 23px;\n      top: 31px;\n      width: 100px;\n      height: 5px;\n      border-radius: 999px;\n      background: var(--navy);\n      transform: rotate(-8deg);\n    }\n\n    .ols-mole-mass .ols-mole-stem {\n      left: 71px;\n      top: 33px;\n      width: 5px;\n      height: 42px;\n      border-radius: 999px;\n      background: rgba(28,36,75,0.45);\n    }\n\n    .ols-mole-mass .ols-mole-scale {\n      left: 52px;\n      top: 72px;\n      width: 43px;\n      height: 6px;\n      border-radius: 999px;\n      background: rgba(28,36,75,0.45);\n    }\n\n    .ols-mole-mass .ols-mole-pan {\n      width: 42px;\n      height: 15px;\n      border: 3px solid rgba(37,99,235,0.65);\n      border-top: none;\n      border-radius: 0 0 18px 18px;\n    }\n\n    .ols-mole-mass .ols-mole-pan.p1 { left: 13px; top: 51px; }\n    .ols-mole-mass .ols-mole-pan.p2 { right: 12px; top: 37px; border-color: rgba(201,151,58,0.75); }\n    .ols-mole-mass .ols-mole-label.l1 { left: 10px; top: 8px; color: var(--blue); }\n    .ols-mole-mass .ols-mole-label.l2 { right: 12px; top: 8px; color: var(--gold); }\n\n    .ols-mole-calc .ols-mole-circle {\n      width: 76px;\n      height: 76px;\n      left: 36px;\n      top: 8px;\n      border-radius: 50%;\n      border: 3px solid rgba(37,99,235,0.26);\n      background: #ffffff;\n      box-shadow: 0 8px 20px rgba(37,99,235,0.10);\n    }\n\n    .ols-mole-calc .ols-mole-line.v { left: 73px; top: 12px; width: 3px; height: 68px; background: rgba(28,36,75,0.18); }\n    .ols-mole-calc .ols-mole-line.h { left: 44px; top: 45px; width: 59px; height: 3px; background: rgba(28,36,75,0.18); }\n    .ols-mole-calc .ols-mole-label.n { left: 64px; top: 24px; color: var(--blue); font-size: 18px; }\n    .ols-mole-calc .ols-mole-label.m { left: 48px; top: 58px; color: var(--navy); }\n    .ols-mole-calc .ols-mole-label.mr { left: 80px; top: 58px; color: var(--gold); }\n    .ols-mole-calc .ols-mole-label.eq { right: 3px; top: 38px; color: var(--navy); }\n\n    .ols-mole-react .ols-mole-box {\n      width: 34px;\n      height: 34px;\n      border-radius: 12px;\n      display: grid;\n      place-items: center;\n      font-size: 14px;\n      font-weight: 800;\n      color: #ffffff;\n      background: var(--blue);\n      box-shadow: 0 8px 18px rgba(37,99,235,0.18);\n    }\n\n    .ols-mole-react .ols-mole-box.b1 { left: 9px; top: 29px; }\n    .ols-mole-react .ols-mole-box.b2 { left: 52px; top: 29px; background: var(--navy); }\n    .ols-mole-react .ols-mole-box.b3 { right: 8px; top: 29px; background: var(--gold); }\n    .ols-mole-react .ols-mole-label.plus { left: 42px; top: 39px; color: var(--navy); }\n    .ols-mole-react .ols-mole-arrow { left: 92px; top: 45px; width: 28px; height: 4px; background: rgba(201,151,58,0.86); border-radius: 999px; }\n    .ols-mole-react .ols-mole-arrow::after { content: \"\"; position: absolute; right: -1px; top: 50%; transform: translateY(-50%); border-left: 10px solid rgba(201,151,58,0.86); border-top: 6px solid transparent; border-bottom: 6px solid transparent; }\n    .ols-mole-react .ols-mole-label.ratio { left: 19px; bottom: 4px; color: var(--blue); }\n\n    .ols-mole-yield .ols-mole-flask {\n      left: 50px;\n      top: 12px;\n      width: 50px;\n      height: 64px;\n      border: 4px solid rgba(28,36,75,0.72);\n      border-top: none;\n      border-radius: 10px 10px 22px 22px;\n      background: linear-gradient(180deg, transparent 42%, rgba(37,99,235,0.16) 43%);\n    }\n\n    .ols-mole-yield .ols-mole-stem {\n      left: 62px;\n      top: 2px;\n      width: 25px;\n      height: 20px;\n      border: 4px solid rgba(28,36,75,0.72);\n      border-bottom: none;\n      border-radius: 8px 8px 0 0;\n    }\n\n    .ols-mole-yield .ols-mole-label.percent { left: 53px; top: 43px; color: var(--blue); font-size: 18px; }\n    .ols-mole-yield .ols-mole-arrow { right: 20px; top: 31px; width: 3px; height: 42px; border-radius: 999px; background: rgba(201,151,58,0.86); }\n    .ols-mole-yield .ols-mole-arrow::after { content: \"\"; position: absolute; left: 50%; bottom: -1px; transform: translateX(-50%); border-top: 10px solid rgba(201,151,58,0.86); border-left: 6px solid transparent; border-right: 6px solid transparent; }\n    .ols-mole-yield .ols-mole-label.less { right: 5px; top: 7px; color: var(--gold); }\n\n    .ols-mole-economy .ols-mole-circle {\n      width: 19px;\n      height: 19px;\n      border-radius: 50%;\n      background: var(--blue);\n      box-shadow: 0 6px 14px rgba(37,99,235,0.20);\n    }\n\n    .ols-mole-economy .ols-mole-circle.c1 { left: 28px; top: 17px; background: var(--navy); }\n    .ols-mole-economy .ols-mole-circle.c2 { left: 54px; top: 28px; }\n    .ols-mole-economy .ols-mole-circle.c3 { left: 34px; top: 52px; background: var(--gold); }\n    .ols-mole-economy .ols-mole-circle.c4 { right: 39px; top: 28px; background: #3f8f46; }\n    .ols-mole-economy .ols-mole-circle.c5 { right: 18px; top: 52px; background: #c81e1e; opacity: 0.70; }\n    .ols-mole-economy .ols-mole-arrow { left: 76px; top: 42px; width: 28px; height: 4px; background: rgba(201,151,58,0.86); border-radius: 999px; }\n    .ols-mole-economy .ols-mole-arrow::after { content: \"\"; position: absolute; right: -1px; top: 50%; transform: translateY(-50%); border-left: 10px solid rgba(201,151,58,0.86); border-top: 6px solid transparent; border-bottom: 6px solid transparent; }\n    .ols-mole-economy .ols-mole-tick { right: 48px; top: 8px; width: 23px; height: 12px; border-left: 4px solid #3f8f46; border-bottom: 4px solid #3f8f46; transform: rotate(-45deg); }\n    .ols-mole-economy .ols-mole-label.waste { right: 2px; bottom: 6px; color: #c81e1e; }\n\n    .ols-mole-card h3 {\n      position: relative;\n      z-index: 1;\n      margin: 0 0 10px;\n      font-size: 23px;\n      line-height: 1.2;\n      font-weight: 800;\n      letter-spacing: -0.02em;\n      color: #111827;\n    }\n\n    .ols-mole-card p {\n      position: relative;\n      z-index: 1;\n      margin: 0;\n      font-size: 15px;\n      line-height: 1.6;\n      font-weight: 300;\n      color: var(--body-text);\n    }\n\n    .ols-mole-card,\n    .ols-mole-card *,\n    .ols-mole-card:hover,\n    .ols-mole-card:hover *,\n    .ols-related-item,\n    .ols-related-item *,\n    .ols-related-item:hover,\n    .ols-related-item:hover * {\n      text-decoration: none !important;\n    }\n\n    .ols-mole-meta {\n      position: relative;\n      z-index: 1;\n      display: inline-flex;\n      align-items: center;\n      justify-content: center;\n      margin-top: 20px;\n      padding: 10px 14px;\n      border-radius: 999px;\n      background: var(--navy);\n      color: #ffffff;\n      font-size: 13px;\n      font-weight: 700;\n      width: fit-content;\n      transition: background 0.22s ease, transform 0.22s ease;\n    }\n\n    .ols-mole-card:hover .ols-mole-meta {\n      background: var(--blue);\n      transform: translateX(4px);\n    }\n\n    .ols-related-grid {\n      display: grid;\n      grid-template-columns: repeat(3, minmax(0, 1fr));\n      gap: 16px;\n      margin-top: 18px;\n    }\n\n    .ols-related-item {\n      border: 1px solid var(--border);\n      border-radius: 18px;\n      padding: 18px;\n      background: #ffffff;\n      color: var(--navy);\n      text-decoration: none;\n      font-weight: 600;\n      line-height: 1.5;\n      transition: transform 0.2s ease, box-shadow 0.2s ease, color 0.2s ease;\n    }\n\n    .ols-related-item:hover {\n      transform: translateY(-2px);\n      box-shadow: 0 10px 22px rgba(28, 36, 75, 0.08);\n      color: var(--blue);\n    }\n\n    .ols-attribution-card {\n      background: linear-gradient(135deg, #ffffff 0%, #f8fbff 100%);\n    }\n\n    .ols-attribution-card p {\n      margin: 0;\n      font-size: 14px;\n      color: var(--grey-text);\n    }\n\n    @media (max-width: 1050px) {\n      .ols-revision-layout { grid-template-columns: 1fr; }\n      .ols-sidebar { position: relative; top: auto; }\n      .ols-topic-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }\n      .ols-subtopic-list { grid-template-columns: 1fr; }\n      .ols-main { max-width: none; }\n      .ols-related-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }\n    }\n\n    @media (max-width: 760px) {\n      .ols-revision-layout { padding: 14px 12px 44px; }\n      .ols-title-card, .ols-note-card, .ols-related-card, .ols-attribution-card { padding: 24px 18px; border-radius: 22px; }\n      .ols-note-title { align-items: flex-start; }\n      .ols-topic-list, .ols-mole-grid, .ols-related-grid { grid-template-columns: 1fr; }\n      .ols-subtopic-list { margin-left: 8px; }\n      .ols-author { align-items: flex-start; padding: 22px 18px; border-radius: 22px; }\n      .ols-author-avatar-img { width: 72px; height: 72px; }\n      .ols-author-title { font-size: 24px; }\n      .ols-author-description { font-size: 15px; }\n      .ols-mole-card { min-height: 255px; }\n    }\n\n    \/* =========================================================\n       COLOURFUL LANDING PAGE CARD VISUALS\n       Inspired by the Topic 2 landing page card system.\n    ========================================================= *\/\n\n    .ols-mole-grid {\n      grid-template-columns: repeat(2, minmax(0, 1fr)) !important;\n      gap: 22px !important;\n    }\n\n    .ols-mole-card {\n      display: flex !important;\n      flex-direction: column !important;\n      padding: 0 !important;\n      min-height: 0 !important;\n      border-radius: 24px !important;\n      overflow: hidden !important;\n      background: #ffffff !important;\n      box-shadow: 0 14px 34px rgba(28, 36, 75, 0.10) !important;\n      transition:\n        transform 0.28s cubic-bezier(0.34, 1.56, 0.64, 1),\n        box-shadow 0.28s ease,\n        border-color 0.28s ease !important;\n    }\n\n    .ols-mole-card:hover {\n      transform: translateY(-10px) scale(1.02) !important;\n      box-shadow: 0 28px 56px rgba(28, 36, 75, 0.16) !important;\n      border-color: rgba(37, 99, 235, 0.35) !important;\n    }\n\n    .ols-mole-card::before {\n      display: none !important;\n    }\n\n    .ols-mole-card-img-wrap {\n      position: relative;\n      width: 100%;\n      aspect-ratio: 4 \/ 3;\n      overflow: hidden;\n      background: var(--soft-blue);\n    }\n\n    .ols-mole-card-img-wrap::after {\n      content: \"\";\n      position: absolute;\n      inset: 0;\n      background: linear-gradient(180deg, transparent 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}\n\n    @media (max-width: 760px) {\n      .ols-mole-simple-symbol {\n        transform: scale(0.94);\n      }\n    }\n\n  <\/style>\n\n  <aside class=\"ols-sidebar\">\r\n  <div class=\"ols-sidebar-header\">\r\n    <h3>Revision Notes<\/h3>\r\n    <p>A Level Chemistry<\/p>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Topic 5 Formulae, Equations and Amounts of Substance<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/\">Equations and Reaction Types<\/a>\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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/ionic-and-full-equations\/\">Ionic and Full 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\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/\">Mole Calculations<\/a>\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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-of-substance\/empirical-and-molecular-formulae\/\">Empirical and Molecular Formulae<\/a>\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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/\">Calculations with Solutions and Gases<\/a>\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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-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\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/titration-calculations\/\">Titration Calculations<\/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\/topic-5-formulae-equations-and-amounts-of-substance\/measurement-uncertainty-and-errors\/\">Measurement Uncertainty and Errors<\/a>\r\n      <\/li>\r\n\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/risks-hazards-and-practical-precautions\/\">Risks, Hazards and Practical Precautions<\/a>\r\n      <\/li>\r\n\r\n    <\/ul>\r\n  <\/div>\r\n\r\n  <div class=\"ols-topic-group\">\r\n    <h4>Next Topics<\/h4>\r\n\r\n    <ul class=\"ols-topic-list\">\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-6-organic-chemistry-i\/\">Topic 6 Organic Chemistry I<\/a>\r\n      <\/li>\r\n      <li>\r\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>\r\n      <\/li>\r\n      <li>\r\n        <a href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-4-inorganic-chemistry-and-the-periodic-table\/\">Topic 4 Inorganic Chemistry &amp; The Periodic Table<\/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(\/\\\/+$\/, '')\r\n      .toLowerCase();\r\n  }\r\n\r\n  function 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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-5-formulae-equations-and-amounts-of-substance\/\">Topic 5 Formulae, Equations and Amounts of Substance<\/a> \/\n        <span>Mole Calculations<\/span>\n      <\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Mole Calculations<\/h1>\n        <p class=\"ols-page-intro\">Use this landing page to move quickly between the key mole calculation revision pages for Topic 5. Each card links to a focused page covering relative masses, mole equations, reacting masses, percentage yield and atom economy.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">Exam board: Edexcel<\/div>\n          <div class=\"ols-badge\">Topic 5: Formulae, Equations &amp; Amounts of Substance<\/div>\n          <div class=\"ols-badge\">Unit: Paper 1<\/div>\n          <div class=\"ols-badge\">9CH0\/01<\/div>\n          <div class=\"ols-badge\">Level: A Level Chemistry<\/div>\n        <\/div>\n\n        <div class=\"ols-author\">\n          <img decoding=\"async\" class=\"ols-author-avatar-img\" src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/05\/Author-Profile.jpeg\" alt=\"Dr. Mohammed Al-Fatah\">\n\n          <div class=\"ols-author-content\">\n            <h2 class=\"ols-author-title\">Written by:<br><span>Dr. Mohammed Al-Fatah<\/span><\/h2>\n            <p class=\"ols-author-description\">Chemistry specialist revision notes for A Level Chemistry.<\/p>\n\n            <a class=\"ols-linkedin-pill\" href=\"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\" target=\"_blank\" rel=\"noopener noreferrer\">\n              <svg class=\"ols-linkedin-icon\" viewBox=\"0 0 24 24\" fill=\"currentColor\" aria-hidden=\"true\">\n                <path d=\"M4.98 3.5C4.98 4.88 3.86 6 2.48 6S0 4.88 0 3.5 1.12 1 2.48 1s2.5 1.12 2.5 2.5zM.5 8h4V24h-4V8zm7 0h3.8v2.2h.1c.5-.9 1.8-2.2 3.9-2.2 4.2 0 5 2.8 5 6.4V24h-4v-7.6c0-1.8 0-4.2-2.6-4.2s-3 2-3 4v7.8h-4V8z\"><\/path>\n              <\/svg>\n              View LinkedIn Profile\n            <\/a>\n          <\/div>\n        <\/div>\n      <\/header>\n\n      <article class=\"ols-note-card soft\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">1<\/div>\n          <h2>Choose a Mole Calculations Page<\/h2>\n        <\/div>\n\n        <p>Mole calculations connect the symbolic equation to measurable quantities in the laboratory. These pages build from comparing masses and using the mole equation through to reacting mass calculations, percentage yield and atom economy.<\/p>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Key idea:<\/strong> Mole calculations depend on the balanced equation, relative formula mass, amount in moles and the relationship between theoretical and practical quantities.<\/p>\n        <\/div>\n\n        <div class=\"ols-mole-grid\">\n          <a class=\"ols-mole-card ols-mole-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/comparing-masses-of-substances\/\">\n            <div class=\"ols-mole-card-img-wrap\">\n              <div class=\"ols-mole-visual ols-mole-visual--mass\">\n                <div class=\"ols-mole-visual-panel\">\n                  <div class=\"ols-mole-visual-kicker\">Relative mass<\/div>\n                  <div class=\"ols-mole-simple-symbol ols-mole-simple-symbol--mass\" aria-hidden=\"true\">\n                    <span>A<sub>r<\/sub><\/span>\n                    <span>M<sub>r<\/sub><\/span>\n                  <\/div>\n                  <div class=\"ols-mole-visual-main\">Comparing<br>Masses<\/div>\n                  <div class=\"ols-mole-visual-sub\">A<sub>r<\/sub>, M<sub>r<\/sub> and formula mass<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-mole-card-num\">1<\/div>\n              <span class=\"ols-mole-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-mole-card-body\">\n              <h3>Comparing Masses of Substances<\/h3>\n              <p>Revise relative atomic mass, relative formula mass and how chemists compare the masses of particles and compounds.<\/p>\n              <span class=\"ols-mole-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n\n          <a class=\"ols-mole-card ols-mole-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/calculations-involving-moles\/\">\n            <div class=\"ols-mole-card-img-wrap\">\n              <div class=\"ols-mole-visual ols-mole-visual--calc\">\n                <div class=\"ols-mole-visual-panel\">\n                  <div class=\"ols-mole-visual-kicker\">Core equation<\/div>\n                  <div class=\"ols-mole-simple-symbol ols-mole-simple-symbol--formula\" aria-hidden=\"true\">\n                    <span>n<\/span>\n                    <small>=<\/small>\n                    <span>m<\/span>\n                    <small>\u00f7<\/small>\n                    <span>M<sub>r<\/sub><\/span>\n                  <\/div>\n                  <div class=\"ols-mole-visual-main\">Mole<br>Equation<\/div>\n                  <div class=\"ols-mole-visual-sub\">amount, mass and relative formula mass<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-mole-card-num\">2<\/div>\n              <span class=\"ols-mole-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-mole-card-body\">\n              <h3>Calculations involving Moles<\/h3>\n              <p>Practise using amount of substance, mass and relative formula mass in the core mole calculation relationship.<\/p>\n              <span class=\"ols-mole-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n\n          <a class=\"ols-mole-card ols-mole-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/calculations-using-reacting-masses\/\">\n            <div class=\"ols-mole-card-img-wrap\">\n              <div class=\"ols-mole-visual ols-mole-visual--react\">\n                <div class=\"ols-mole-visual-panel\">\n                  <div class=\"ols-mole-visual-kicker\">Balanced ratios<\/div>\n                  <div class=\"ols-mole-simple-symbol ols-mole-simple-symbol--ratio\" aria-hidden=\"true\">\n                    <span>2<\/span>\n                    <small>:<\/small>\n                    <span>1<\/span>\n                    <small>:<\/small>\n                    <span>2<\/span>\n                  <\/div>\n                  <div class=\"ols-mole-visual-main\">Reacting<br>Masses<\/div>\n                  <div class=\"ols-mole-visual-sub\">moles, stoichiometry and balanced equations<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-mole-card-num\">3<\/div>\n              <span class=\"ols-mole-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-mole-card-body\">\n              <h3>Calculations using Reacting Masses<\/h3>\n              <p>Use balanced equations and mole ratios to calculate the mass of reactants needed or products formed.<\/p>\n              <span class=\"ols-mole-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n\n          <a class=\"ols-mole-card ols-mole-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/the-yield-of-a-reaction\/\">\n            <div class=\"ols-mole-card-img-wrap\">\n              <div class=\"ols-mole-visual ols-mole-visual--yield\">\n                <div class=\"ols-mole-visual-panel\">\n                  <div class=\"ols-mole-simple-symbol ols-mole-simple-symbol--yield\" aria-hidden=\"true\">\n                    <span>%<\/span>\n                  <\/div>\n                  <div class=\"ols-mole-visual-main\">Percentage<br>Yield<\/div>\n                  <div class=\"ols-mole-visual-sub\">actual yield and theoretical yield<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-mole-card-num\">4<\/div>\n              <span class=\"ols-mole-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-mole-card-body\">\n              <h3>The Yield of a Reaction<\/h3>\n              <p>Understand theoretical yield, actual yield and why percentage yield is often less than 100% in practical chemistry.<\/p>\n              <span class=\"ols-mole-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n\n          <a class=\"ols-mole-card ols-mole-card--available\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/atom-economy\/\">\n            <div class=\"ols-mole-card-img-wrap\">\n              <div class=\"ols-mole-visual ols-mole-visual--economy\">\n                <div class=\"ols-mole-visual-panel\">\n                  <div class=\"ols-mole-visual-kicker\">Green chemistry<\/div>\n                  <div class=\"ols-mole-simple-symbol ols-mole-simple-symbol--economy\" aria-hidden=\"true\">\n                    <span>\u2713<\/span>\n                  <\/div>\n                  <div class=\"ols-mole-visual-main\">Atom<br>Economy<\/div>\n                  <div class=\"ols-mole-visual-sub\">desired product and waste reduction<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-mole-card-num\">5<\/div>\n              <span class=\"ols-mole-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-mole-card-body\">\n              <h3>Atom Economy<\/h3>\n              <p>Revise how atom economy measures the proportion of reactant atoms converted into the desired product.<\/p>\n              <span class=\"ols-mole-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n        <\/div>\n      <\/article>\n\n      <article class=\"ols-note-card purple\">\n        <div class=\"ols-note-title\">\n          <div class=\"ols-note-icon\">2<\/div>\n          <h2>How These Pages Fit Together<\/h2>\n        <\/div>\n        <p>Start with relative masses, then move to the mole equation. Once the amount in moles is secure, reacting mass calculations become a matter of using the balanced equation ratio correctly.<\/p>\n        <p>Percentage yield and atom economy then extend the same quantitative ideas into practical efficiency and green chemistry. These two ideas are especially useful for exam questions that ask students to interpret why a reaction may not produce the maximum possible useful product.<\/p>\n        <div class=\"ols-key-box\">\n          <p><strong>Exam focus:<\/strong> Always convert through moles when comparing different substances in a balanced chemical equation.<\/p>\n        <\/div>\n      <\/article>\n\n      <section class=\"ols-related-card\">\n        <h2>Related Topic 5 Pages<\/h2>\n        <p>These pages support the calculation skills needed for mole calculations and equation-based chemistry.<\/p>\n        <div class=\"ols-related-grid\">\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/atoms-elements-and-molecules\/\">Atoms, Elements and Molecules<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/equations-and-reaction-types\/\">Equations and Reaction Types<\/a>\n          <a class=\"ols-related-item\" href=\"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/concentrations\/\">Concentration Calculations<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card\">\n        <p><strong>OLS Author Copyright Footprint:<\/strong> This OLS revision landing page was created for Online Learning System by Dr. Mohammed Al-Fatah. All content, layout and educational sequencing are part of the OLS Revision Notes project.<\/p>\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-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/#webpage\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/\",\n            \"name\": \"Mole Calculations - Edexcel A Level Chemistry Revision Notes\",\n            \"description\": \"A Level Chemistry landing page for mole calculations, including comparing masses, mole calculations, reacting masses, percentage yield and atom economy.\",\n            \"inLanguage\": \"en-GB\",\n            \"isPartOf\": {\n              \"@type\": \"WebSite\",\n              \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/#website\",\n              \"name\": \"Online Learning System\",\n              \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/\"\n            },\n            \"about\": [\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Mole calculations\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Relative formula mass\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Reacting masses\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Percentage yield\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Atom economy\"\n              }\n            ],\n            \"author\": {\n              \"@type\": \"Person\",\n              \"name\": \"Dr. Mohammed Al-Fatah\",\n              \"url\": \"https:\/\/www.linkedin.com\/in\/doctormohammedfatah\/\"\n            },\n            \"publisher\": {\n              \"@type\": \"Organization\",\n              \"name\": \"Online Learning System\",\n              \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/\"\n            }\n          },\n          {\n            \"@type\": \"BreadcrumbList\",\n            \"@id\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/#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\": \"Edexcel\",\n                \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/\"\n              },\n              {\n                \"@type\": \"ListItem\",\n                \"position\": 4,\n                \"name\": \"Topic 5 Formulae, Equations and Amounts of Substance\",\n                \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/\"\n              },\n              {\n                \"@type\": \"ListItem\",\n                \"position\": 5,\n                \"name\": \"Mole Calculations\",\n                \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/mole-calculations\/\"\n              }\n            ]\n          }\n        ]\n      }\n      <\/script>\n    <\/main>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>Revision Notes \/ A Level Chemistry \/ Edexcel \/ Topic 5 Formulae, Equations and Amounts of Substance \/ Mole Calculations Mole Calculations Use this landing page to move quickly between the key mole calculation revision pages for Topic 5. Each card links to a focused page covering relative masses, mole equations, reacting masses, percentage yield [&hellip;]<\/p>\n","protected":false},"author":12,"featured_media":0,"parent":4501,"menu_order":2,"comment_status":"closed","ping_status":"closed","template":"","meta":{"productId":0,"courseId":0,"footnotes":""},"class_list":["post-4684","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4684","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=4684"}],"version-history":[{"count":0,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4684\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/pages\/4501"}],"wp:attachment":[{"href":"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-json\/wp\/v2\/media?parent=4684"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}