{"id":4752,"date":"2026-06-02T07:46:55","date_gmt":"2026-06-02T06:46:55","guid":{"rendered":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/"},"modified":"2026-06-02T11:32:51","modified_gmt":"2026-06-02T10:32:51","slug":"calculations-with-solutions-and-gases","status":"publish","type":"page","link":"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/","title":{"rendered":"Calculations with Solutions and Gases"},"content":{"rendered":"\n<section class=\"ols-revision-page ols-calculations-solutions-gases-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-csg-grid {\n      display: grid;\n      grid-template-columns: repeat(3, minmax(0, 1fr));\n      gap: 18px;\n      margin-top: 26px;\n    }\n\n    .ols-csg-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-csg-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-csg-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-csg-card:hover::before {\n      transform: scale(1.22);\n      background: rgba(37, 99, 235, 0.13);\n    }\n\n    .ols-csg-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-csg-icon {\n      position: relative;\n      width: 150px;\n      height: 94px;\n    }\n\n    .ols-csg-line,\n    .ols-csg-arrow,\n    .ols-csg-label-mini,\n    .ols-csg-box,\n    .ols-csg-dot,\n    .ols-csg-bubble,\n    .ols-csg-precipitate,\n    .ols-csg-swap {\n      position: absolute;\n      display: block;\n    }\n\n    .ols-csg-equation .ols-csg-box {\n      top: 25px;\n      width: 39px;\n      height: 39px;\n      border-radius: 13px;\n      display: grid;\n      place-items: center;\n      color: #ffffff;\n      font-size: 15px;\n      font-weight: 800;\n      box-shadow: 0 8px 18px rgba(28, 36, 75, 0.16);\n    }\n\n    .ols-csg-equation .b1 { left: 8px; background: var(--blue); }\n    .ols-csg-equation .b2 { left: 56px; background: var(--navy); }\n    .ols-csg-equation .b3 { right: 8px; background: var(--gold); }\n    .ols-csg-equation .ols-csg-label-mini { left: 50px; top: 34px; color: var(--navy); font-size: 19px; font-weight: 800; }\n    .ols-csg-equation .ols-csg-arrow { left: 96px; top: 43px; width: 36px; height: 3px; border-radius: 999px; background: rgba(201, 151, 58, 0.88); }\n    .ols-csg-equation .ols-csg-arrow::after { content: \"\"; position: absolute; right: -1px; top: 50%; transform: translateY(-50%); border-left: 10px solid rgba(201,151,58,0.88); border-top: 6px solid transparent; border-bottom: 6px solid transparent; }\n\n    .ols-csg-acid .ols-csg-bubble {\n      width: 18px;\n      height: 18px;\n      border-radius: 50%;\n      border: 3px solid rgba(37, 99, 235, 0.70);\n      background: rgba(238, 244, 255, 0.80);\n      box-shadow: 0 7px 16px rgba(37, 99, 235, 0.12);\n    }\n\n    .ols-csg-acid .c1 { left: 38px; top: 55px; }\n    .ols-csg-acid .c2 { left: 60px; top: 35px; transform: scale(0.82); }\n    .ols-csg-acid .c3 { left: 82px; top: 19px; transform: scale(0.68); }\n    .ols-csg-acid .flask {\n      left: 32px;\n      bottom: 9px;\n      width: 86px;\n      height: 44px;\n      border: 4px solid rgba(28, 36, 75, 0.70);\n      border-top: none;\n      border-radius: 8px 8px 28px 28px;\n      background: linear-gradient(180deg, rgba(255,247,237,0) 30%, rgba(201,151,58,0.25) 31%, rgba(201,151,58,0.25) 100%);\n    }\n\n    .ols-csg-acid .neck {\n      left: 64px;\n      top: 8px;\n      width: 22px;\n      height: 34px;\n      border: 4px solid rgba(28, 36, 75, 0.70);\n      border-bottom: none;\n      border-radius: 8px 8px 0 0;\n    }\n\n    .ols-csg-acid .ols-csg-label-mini { right: 4px; top: 8px; color: var(--gold); font-size: 13px; font-weight: 800; }\n\n    .ols-csg-displacement .ols-csg-line {\n      height: 4px;\n      border-radius: 999px;\n      background: rgba(28, 36, 75, 0.28);\n    }\n\n    .ols-csg-displacement .l1 { left: 16px; right: 16px; top: 32px; }\n    .ols-csg-displacement .l2 { left: 16px; right: 16px; bottom: 30px; }\n    .ols-csg-displacement .ols-csg-dot {\n      width: 23px;\n      height: 23px;\n      border-radius: 50%;\n      display: grid;\n      place-items: center;\n      color: #ffffff;\n      font-size: 12px;\n      font-weight: 800;\n      box-shadow: 0 8px 18px rgba(28,36,75,0.18);\n    }\n\n    .ols-csg-displacement .d1 { left: 22px; top: 22px; background: var(--blue); }\n    .ols-csg-displacement .d2 { right: 22px; bottom: 20px; background: var(--navy); }\n    .ols-csg-displacement .d3 { right: 22px; top: 22px; background: var(--gold); }\n    .ols-csg-displacement .d4 { left: 22px; bottom: 20px; background: #c81e1e; }\n    .ols-csg-displacement .ols-csg-swap { left: 60px; top: 35px; color: var(--gold); font-size: 28px; font-weight: 800; transform: rotate(-12deg); }\n\n    .ols-csg-precipitation .tube {\n      top: 10px;\n      width: 42px;\n      height: 76px;\n      border: 4px solid rgba(28, 36, 75, 0.68);\n      border-top: none;\n      border-radius: 0 0 22px 22px;\n      background: linear-gradient(180deg, rgba(238,244,255,0) 34%, rgba(238,244,255,0.90) 35%, rgba(238,244,255,0.90) 100%);\n    }\n\n    .ols-csg-precipitation .t1 { left: 19px; transform: rotate(-8deg); }\n    .ols-csg-precipitation .t2 { right: 19px; transform: rotate(8deg); }\n    .ols-csg-precipitation .ols-csg-precipitate {\n      left: 48px;\n      bottom: 10px;\n      width: 54px;\n      height: 18px;\n      border-radius: 999px 999px 12px 12px;\n      background: rgba(201,151,58,0.70);\n      box-shadow: 0 9px 18px rgba(201,151,58,0.20);\n    }\n\n    .ols-csg-precipitation .ols-csg-arrow { left: 62px; top: 33px; width: 26px; height: 3px; border-radius: 999px; background: rgba(201, 151, 58, 0.88); transform: rotate(90deg); }\n    .ols-csg-precipitation .ols-csg-arrow::after { content: \"\"; position: absolute; right: -1px; top: 50%; transform: translateY(-50%); border-left: 10px solid rgba(201,151,58,0.88); border-top: 6px solid transparent; border-bottom: 6px solid transparent; }\n    .ols-csg-precipitation .ols-csg-label-mini { left: 48px; top: 7px; color: var(--blue); font-size: 12px; font-weight: 800; }\n\n\n    .ols-csg-molar .ols-csg-tube {\n      position: absolute;\n      left: 53px;\n      top: 8px;\n      width: 46px;\n      height: 78px;\n      border: 4px solid rgba(28, 36, 75, 0.70);\n      border-top: none;\n      border-radius: 0 0 23px 23px;\n      background: linear-gradient(180deg, rgba(238,244,255,0) 34%, rgba(238,244,255,0.95) 35%, rgba(238,244,255,0.95) 100%);\n    }\n\n    .ols-csg-molar .ols-csg-bubble {\n      width: 16px;\n      height: 16px;\n      border-radius: 50%;\n      border: 3px solid rgba(37, 99, 235, 0.72);\n      background: rgba(238, 244, 255, 0.82);\n      box-shadow: 0 7px 16px rgba(37, 99, 235, 0.12);\n    }\n\n    .ols-csg-molar .g1 { left: 33px; top: 50px; }\n    .ols-csg-molar .g2 { left: 83px; top: 38px; transform: scale(0.84); }\n    .ols-csg-molar .g3 { left: 99px; top: 16px; transform: scale(0.66); }\n    .ols-csg-molar .ols-csg-label-mini { left: 9px; top: 8px; color: var(--gold); font-size: 13px; font-weight: 800; }\n\n    .ols-csg-solution .ols-csg-flask {\n      left: 31px;\n      bottom: 7px;\n      width: 88px;\n      height: 50px;\n      border: 4px solid rgba(28, 36, 75, 0.70);\n      border-top: none;\n      border-radius: 9px 9px 30px 30px;\n      background: linear-gradient(180deg, rgba(238,244,255,0) 28%, rgba(37,99,235,0.18) 29%, rgba(37,99,235,0.18) 100%);\n    }\n\n    .ols-csg-solution .ols-csg-neck {\n      left: 64px;\n      top: 6px;\n      width: 22px;\n      height: 36px;\n      border: 4px solid rgba(28, 36, 75, 0.70);\n      border-bottom: none;\n      border-radius: 8px 8px 0 0;\n    }\n\n    .ols-csg-solution .ols-csg-dot {\n      width: 12px;\n      height: 12px;\n      border-radius: 50%;\n      background: var(--blue);\n      opacity: 0.78;\n    }\n\n    .ols-csg-solution .s1 { left: 45px; top: 58px; }\n    .ols-csg-solution .s2 { left: 71px; top: 68px; transform: scale(0.82); }\n    .ols-csg-solution .s3 { left: 95px; top: 55px; transform: scale(0.72); }\n    .ols-csg-solution .ols-csg-label-mini { right: 6px; top: 8px; color: var(--blue); font-size: 13px; font-weight: 800; }\n\n    .ols-csg-ppm .ols-csg-box {\n      width: 31px;\n      height: 31px;\n      border-radius: 10px;\n      display: grid;\n      place-items: center;\n      color: #ffffff;\n      font-size: 12px;\n      font-weight: 800;\n      box-shadow: 0 8px 18px rgba(28, 36, 75, 0.16);\n    }\n\n    .ols-csg-ppm .p1 { left: 8px; top: 14px; background: var(--blue); }\n    .ols-csg-ppm .p2 { left: 47px; top: 14px; background: var(--navy); }\n    .ols-csg-ppm .p3 { left: 86px; top: 14px; background: var(--gold); }\n    .ols-csg-ppm .p4 { left: 125px; top: 14px; background: #c81e1e; }\n    .ols-csg-ppm .ols-csg-line { left: 9px; right: 9px; bottom: 25px; height: 4px; border-radius: 999px; background: rgba(28, 36, 75, 0.22); }\n    .ols-csg-ppm .ols-csg-label-mini { left: 38px; bottom: 5px; color: var(--gold); font-size: 15px; font-weight: 800; }\n\n    .ols-csg-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-csg-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-csg-card,\n    .ols-csg-card *,\n    .ols-csg-card:hover,\n    .ols-csg-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-csg-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-csg-card:hover .ols-csg-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-csg-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; 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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 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   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Formulae, Equations and Amounts of Substance<\/a> \/\n        <span>Calculations with Solutions and Gases<\/span>\n      <\/nav>\n\n      <header class=\"ols-title-card\">\n        <h1>Calculations with Solutions and Gases<\/h1>\n        <p class=\"ols-page-intro\">Use this landing page to move quickly between the key quantitative chemistry pages for solutions and gases in Edexcel Topic 5. Each card links to a focused page covering molar volume calculations, solution concentration calculations and titration calculations.<\/p>\n\n        <div class=\"ols-badges\">\n          <div class=\"ols-badge\">Unit: Paper 1<\/div>\n          <div class=\"ols-badge\">Topic 5: Formulae, Equations and Amounts of Substance<\/div>\n          <div class=\"ols-badge\">9CH0\/01<\/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 Calculations with Solutions and Gases Page<\/h2>\n        <\/div>\n\n        <p>Calculations with solutions and gases connect the mole concept to measurable laboratory quantities. These pages build from calculating gas volumes, through using concentration in mol dm<sup>\u22123<\/sup>, to interpreting very small concentrations expressed in parts per million.<\/p>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Key idea:<\/strong> Quantitative chemistry depends on choosing the correct relationship between amount of substance, volume, concentration and mass, then keeping units consistent throughout the calculation.<\/p>\n        <\/div>\n\n        <div class=\"ols-csg-grid\">\n          <a class=\"ols-csg-card ols-csg-card--available\" 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\/\">\n            <div class=\"ols-csg-card-img-wrap\">\n              <div class=\"ols-csg-visual ols-csg-visual--gas\">\n                <div class=\"ols-csg-visual-panel\">\n                  <div class=\"ols-csg-visual-kicker\">Gas volume<\/div>\n                  <div class=\"ols-csg-simple-symbol\" aria-hidden=\"true\">V = n \u00d7 24<\/div>\n                  <div class=\"ols-csg-visual-main\">Molar<br>Volume<\/div>\n                  <div class=\"ols-csg-visual-sub\">gas volume and amount in moles<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-csg-card-num\">1<\/div>\n              <span class=\"ols-csg-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-csg-card-body\">\n              <h3>Molar Volume Calculations<\/h3>\n              <p>Revise how the amount of gas in moles links to gas volume, including the use of molar gas volume in calculations.<\/p>\n              <span class=\"ols-csg-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n\n          <a class=\"ols-csg-card ols-csg-card--available\" 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\/\">\n            <div class=\"ols-csg-card-img-wrap\">\n              <div class=\"ols-csg-visual ols-csg-visual--solution\">\n                <div class=\"ols-csg-visual-panel\">\n                  <div class=\"ols-csg-visual-kicker\">Solution concentration<\/div>\n                  <div class=\"ols-csg-simple-symbol\" aria-hidden=\"true\">c = n\/V<\/div>\n                  <div class=\"ols-csg-visual-main\">Solution<br>Concentration<\/div>\n                  <div class=\"ols-csg-visual-sub\">amount, volume and concentration<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-csg-card-num\">2<\/div>\n              <span class=\"ols-csg-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-csg-card-body\">\n              <h3>Concentrations of Solutions<\/h3>\n              <p>Practise using concentration, volume and amount of substance in mol dm<sup>\u22123<\/sup> calculations.<\/p>\n              <span class=\"ols-csg-meta\">Start revising<\/span>\n            <\/div>\n          <\/a>\n\n          <a class=\"ols-csg-card ols-csg-card--available\" 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\/\">\n            <div class=\"ols-csg-card-img-wrap\">\n              <div class=\"ols-csg-visual ols-csg-visual--titration\">\n                <div class=\"ols-csg-visual-panel\">\n                  <div class=\"ols-csg-visual-kicker\">Volumetric analysis<\/div>\n                  <div class=\"ols-csg-simple-symbol\" aria-hidden=\"true\">cV<\/div>\n                  <div class=\"ols-csg-visual-main\">Titration<br>Calculations<\/div>\n                  <div class=\"ols-csg-visual-sub\">concentration, volume and mole ratios<\/div>\n                <\/div>\n              <\/div>\n              <div class=\"ols-csg-card-num\">3<\/div>\n              <span class=\"ols-csg-card-status\">Available<\/span>\n            <\/div>\n            <div class=\"ols-csg-card-body\">\n              <h3>Titration Calculations<\/h3>\n              <p>Use concentration, volume and balanced equation ratios to calculate unknown concentrations from titration data.<\/p>\n              <span class=\"ols-csg-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\">\u2713<\/div>\n          <h2>How to Use These Pages<\/h2>\n        <\/div>\n\n        <p>Start with molar volume calculations to link gases to amount of substance. Then move to concentrations of solutions, because many titration and practical chemistry questions require confident use of concentration and volume. Finally, use the titration calculations page to connect solution concentration with reacting mole ratios and practical volumetric analysis.<\/p>\n\n        <div class=\"ols-key-box\">\n          <p><strong>Exam focus:<\/strong> Always check units before substituting numbers. 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  }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-course-button-top {\r\n        width: 100%;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-course-cta-stats,\r\n      .ols-course-cta-formulae-amounts .ols-course-cta-features {\r\n        grid-template-columns: 1fr;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-course-animation-wrap {\r\n        padding: 0;\r\n        border-radius: 0;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-animation-frame-shell {\r\n        height: 420px;\r\n        border-radius: 18px;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-animation-play-circle {\r\n        width: 76px;\r\n        height: 76px;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-animation-play-icon {\r\n        border-top-width: 14px;\r\n        border-bottom-width: 14px;\r\n        border-left-width: 22px;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-animation-pause-button {\r\n        left: 12px;\r\n        bottom: 12px;\r\n        min-width: 84px;\r\n        padding: 9px 14px;\r\n        font-size: 13px;\r\n      }\r\n\r\n      .ols-course-cta-formulae-amounts .ols-course-button {\r\n        width: 100%;\r\n      }\r\n    }\r\n  <\/style>\r\n\r\n  <div class=\"ols-course-cta-card\">\r\n\r\n    <div class=\"ols-course-cta-top\">\r\n\r\n      <a class=\"ols-course-cta-image-link\" href=\"https:\/\/onlinelearningsystem.net\/xyz\/shop\" aria-label=\"Open the Edexcel A Level Chemistry Topic 5 Formulae, Equations and Amounts of Substance course page\">\r\n\r\n        <div class=\"ols-course-cta-image\">\r\n          <img decoding=\"async\"\r\n            src=\"https:\/\/www.onlinelearningsystem.net\/xyz\/wp-content\/uploads\/2026\/06\/Edexcel-Topic-5-Formulae-Equations-and-Amounts-of-Substance.jpg\"\r\n            alt=\"Edexcel A Level Chemistry Topic 5 Formulae, Equations and Amounts of Substance course banner\"\r\n          >\r\n        <\/div>\r\n\r\n      <\/a>\r\n\r\n      <div class=\"ols-course-cta-content\">\r\n\r\n        <div class=\"ols-course-cta-header-row\">\r\n\r\n          <div class=\"ols-course-cta-kicker\">\r\n            Complete Topic 5 Formulae, Equations & Amounts of Substance Course\r\n          <\/div>\r\n\r\n          <a class=\"ols-course-button ols-course-button-top\" href=\"https:\/\/onlinelearningsystem.net\/xyz\/shop\">\r\n            View Course\r\n          <\/a>\r\n\r\n        <\/div>\r\n\r\n        <h2>\r\n          Master Formulae, Equations and Amounts of Substance for Edexcel A Level Chemistry\r\n        <\/h2>\r\n\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-intro-stats\">\r\n\r\n      <p class=\"ols-course-cta-intro\">\r\n        Continue from these free revision notes into the full Topic 5 Formulae, Equations and Amounts of Substance course, with guided video teaching, diagnostic MCQ practice, teacher-marked short-answer questions and a specification assignment with a personalised progress report.\r\n      <\/p>\r\n\r\n      <div class=\"ols-course-cta-stats\">\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Guided learning<\/span>\r\n          <strong>Complete Topic 5<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>Video lessons<\/span>\r\n          <strong>Full virtual lesson<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>MCQ practice<\/span>\r\n          <strong>123 marks<\/strong>\r\n        <\/div>\r\n\r\n        <div class=\"ols-course-stat\">\r\n          <span>SAQ practice<\/span>\r\n          <strong>up to 145 marks<\/strong>\r\n        <\/div>\r\n\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-features\">\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Guided video teaching<\/h3>\r\n        <p>\r\n          Learn formulae, balanced equations, ionic equations, relative masses, mole calculations, empirical formulae, reacting masses, gas volumes, percentage yield and atom economy through structured video lessons with worked examples and walkthroughs.\r\n        <\/p>\r\n      <\/div>\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Instant MCQ feedback<\/h3>\r\n        <p>\r\n          Auto-marked MCQ quizzes provide immediate diagnostic feedback for every answer choice.\r\n        <\/p>\r\n      <\/div>\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Teacher-marked SAQs<\/h3>\r\n        <p>\r\n          Submit written exam responses and receive chemistry specialist feedback with improvement guidance.\r\n        <\/p>\r\n      <\/div>\r\n\r\n      <div class=\"ols-course-feature\">\r\n        <h3>Progress tracking<\/h3>\r\n        <p>\r\n          Identify strengths and weaknesses across formulae, equations, mole calculations, concentration, empirical formulae, percentage yield, atom economy and test-tube reactions with targeted reporting.\r\n        <\/p>\r\n      <\/div>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-animation-wrap\">\r\n\r\n      <h3 class=\"ols-course-animation-title\">\r\n        See how the course works\r\n      <\/h3>\r\n\r\n      <div class=\"ols-animation-frame-shell\">\r\n        <iframe\r\n          id=\"olsCourseAnimationFrame005\"\r\n          title=\"OLS course preview animation\"\r\n          loading=\"lazy\"\r\n          referrerpolicy=\"no-referrer\">\r\n        <\/iframe>\r\n\r\n        <button\r\n          class=\"ols-animation-start-overlay\"\r\n          id=\"olsCourseAnimationStart005\"\r\n          type=\"button\"\r\n          aria-label=\"Play OLS course preview animation\">\r\n          <span class=\"ols-animation-start-content\">\r\n            <span class=\"ols-animation-play-circle\" aria-hidden=\"true\">\r\n              <span class=\"ols-animation-play-icon\"><\/span>\r\n            <\/span>\r\n            <span class=\"ols-animation-start-text\">\r\n              Play course preview animation\r\n            <\/span>\r\n          <\/span>\r\n        <\/button>\r\n\r\n        <button\r\n          class=\"ols-animation-pause-button\"\r\n          id=\"olsCourseAnimationPause005\"\r\n          type=\"button\"\r\n          aria-label=\"Pause course preview animation\">\r\n          Pause\r\n        <\/button>\r\n      <\/div>\r\n\r\n      <p class=\"ols-course-video-status\">\r\n        Click play to start the course preview animation.\r\n      <\/p>\r\n\r\n    <\/div>\r\n\r\n    <div class=\"ols-course-cta-bottom\">\r\n\r\n      <a class=\"ols-course-button\" href=\"https:\/\/onlinelearningsystem.net\/xyz\/shop\">\r\n        View Formulae, Equations & Amounts of Substance Topic 5 Course\r\n      <\/a>\r\n\r\n    <\/div>\r\n\r\n  <\/div>\r\n\r\n  <template id=\"olsCourseAnimationTemplate005\">\r\n<!DOCTYPE html>\r\n<html lang=\"en\">\r\n<head>\r\n<meta charset=\"UTF-8\">\r\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\r\n<title>OLS Combined Promo Animation<\/title>\r\n\r\n<style>\r\n*{box-sizing:border-box;}\r\n\r\nhtml.ols-animation-paused *,\r\nhtml.ols-animation-paused *::before,\r\nhtml.ols-animation-paused *::after{\r\n  animation-play-state:paused!important;\r\n}\r\n\r\n:root{\r\n  --ols-video-screen-w:1180;\r\n  --ols-video-screen-h:664;\r\n  --ols-video-screen-scale:1;\r\n  --ols-mcq-screen-w:1360;\r\n  --ols-mcq-screen-h:1130;\r\n  --ols-mcq-screen-scale:1;\r\n  --ols-saq-screen-w:1360;\r\n  --ols-saq-screen-h:965;\r\n  --ols-saq-screen-scale:1;\r\n}\r\n\r\nhtml,\r\nbody{\r\n  width:100%;\r\n  height:100%;\r\n}\r\n\r\nbody{\r\n  margin:0;\r\n  overflow:hidden;\r\n  font-family:Poppins,Arial,sans-serif;\r\n  background:#e9efff;\r\n}\r\n\r\n.ols-combined-stage{\r\n  position:relative;\r\n  width:100vw;\r\n  height:100vh;\r\n  overflow:hidden;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n}\r\n\r\n.ols-scene{\r\n  position:absolute;\r\n  inset:0;\r\n  width:100vw;\r\n  height:100vh;\r\n  opacity:0;\r\n  visibility:hidden;\r\n  pointer-events:none;\r\n}\r\n\r\n.ols-scene.active{\r\n  opacity:1;\r\n  visibility:visible;\r\n  pointer-events:auto;\r\n}\r\n\r\n.ols-scene.fade-out{\r\n  animation:olsSceneFadeOut 0.85s ease forwards;\r\n}\r\n\r\n@keyframes olsSceneFadeOut{\r\n  to{\r\n    opacity:0;\r\n    visibility:hidden;\r\n  }\r\n}\r\n\r\n.ols-title-cursor{\r\n  display:inline-block;\r\n  width:5px;\r\n  height:0.85em;\r\n  background:#1C244B;\r\n  margin-left:8px;\r\n  transform:translateY(8px);\r\n  animation:olsBlink 0.8s infinite;\r\n}\r\n\r\n.cursor{\r\n  display:inline-block;\r\n  width:3px;\r\n  height:28px;\r\n  background:#1c244b;\r\n  margin-left:3px;\r\n  transform:translateY(5px);\r\n  animation:olsBlink 0.8s infinite;\r\n}\r\n\r\n@keyframes olsBlink{\r\n  0%,45%{opacity:1;}\r\n  46%,100%{opacity:0;}\r\n}\r\n\r\n.ols-video-stage,\r\n.ols-mcq-stage,\r\n.ols-saq-stage{\r\n  width:100vw;\r\n  height:100vh;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  padding:0;\r\n  overflow:hidden;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n}\r\n\r\n.ols-video-title-screen,\r\n.ols-mcq-intro-screen,\r\n.ols-saq-intro{\r\n  position:absolute;\r\n  inset:0;\r\n  z-index:50;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  background:\r\n    radial-gradient(circle at top left,rgba(70,127,247,0.14),transparent 34%),\r\n    linear-gradient(135deg,#f8fbff 0%,#e9efff 100%);\r\n  opacity:1;\r\n  visibility:visible;\r\n  pointer-events:none;\r\n}\r\n\r\n.ols-video-title-screen.hide{animation:olsVideoTitleFadeOut 0.85s ease forwards;}\r\n.ols-mcq-intro-screen.hide{animation:olsMcqIntroFadeOut 0.85s ease forwards;}\r\n.ols-saq-intro.hide{animation:olsSaqIntroFadeOut 0.85s ease forwards;}\r\n\r\n@keyframes olsVideoTitleFadeOut{to{opacity:0;visibility:hidden;}}\r\n@keyframes olsMcqIntroFadeOut{to{opacity:0;visibility:hidden;}}\r\n@keyframes olsSaqIntroFadeOut{to{opacity:0;visibility:hidden;}}\r\n\r\n.ols-video-title-wrap,\r\n.ols-mcq-intro-title-wrap,\r\n.ols-saq-intro-title-wrap{\r\n  max-width:1250px;\r\n  padding:0 34px;\r\n  text-align:center;\r\n}\r\n\r\n.ols-video-title,\r\n.ols-mcq-intro-title,\r\n.ols-saq-intro-title{\r\n  margin:0;\r\n  font-family:Poppins,Arial,sans-serif;\r\n  font-size:clamp(52px,8vw,124px);\r\n  font-weight:600;\r\n  line-height:1.08;\r\n  color:#1C244B;\r\n  text-shadow:-9px 0 9px rgba(28,36,75,0.16);\r\n  letter-spacing:-0.045em;\r\n}\r\n\r\n#videoTitleText,\r\n#mcqIntroTitleText,\r\n#saqIntroTitleText{\r\n  white-space:pre-wrap;\r\n}\r\n\r\n.ols-video-scene{\r\n  width:100%;\r\n  height:100%;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n  opacity:0;\r\n  visibility:hidden;\r\n}\r\n\r\n.ols-video-scene.show{\r\n  visibility:visible;\r\n  animation:olsVideoSceneIn 1s ease forwards;\r\n}\r\n\r\n@keyframes olsVideoSceneIn{to{opacity:1;}}\r\n\r\n.ols-video-scale-wrap{\r\n  width:calc(var(--ols-video-screen-w) * 1px);\r\n  height:calc(var(--ols-video-screen-h) * 1px);\r\n  transform:scale(var(--ols-video-screen-scale));\r\n  transform-origin:center center;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:center;\r\n}\r\n\r\n.ols-video-card{\r\n  width:1180px;\r\n  height:664px;\r\n  border-radius:28px;\r\n  overflow:hidden;\r\n  background:#1C244B;\r\n  box-shadow:0 28px 80px rgba(28,36,75,0.28);\r\n  transform:translateY(24px) scale(0.96);\r\n  opacity:0;\r\n}\r\n\r\n.ols-video-scene.show .ols-video-card{\r\n  animation:olsVideoCardIn 1s cubic-bezier(.18,.89,.32,1.12) forwards;\r\n  animation-delay:0.2s;\r\n}\r\n\r\n@keyframes olsVideoCardIn{\r\n  to{\r\n    transform:translateY(0) scale(1);\r\n    opacity:1;\r\n  }\r\n}\r\n\r\n.ols-video-card video{\r\n  display:block;\r\n  width:100%;\r\n  height:100%;\r\n  aspect-ratio:16 \/ 9;\r\n  object-fit:cover;\r\n  border:0;\r\n}\r\n\r\n.ols-mcq-scale-wrap,\r\n.ols-saq-scale-wrap{\r\n  width:calc(var(--ols-mcq-screen-w) * 1px);\r\n  height:calc(var(--ols-mcq-screen-h) * 1px);\r\n  transform:scale(var(--ols-mcq-screen-scale));\r\n  transform-origin:center center;\r\n  display:flex;\r\n  justify-content:center;\r\n  align-items:flex-start;\r\n}\r\n\r\n.ols-saq-scale-wrap{\r\n  width:calc(var(--ols-saq-screen-w) * 1px);\r\n  height:calc(var(--ols-saq-screen-h) * 1px);\r\n  transform:scale(var(--ols-saq-screen-scale));\r\n}\r\n\r\n.ols-mcq-screen{\r\n  width:1360px;\r\n  height:1130px;\r\n  border-radius:22px;\r\n  overflow:hidden;\r\n  background:#eaf0ff;\r\n  box-shadow:0 26px 70px rgba(28,36,75,0.22);\r\n  opacity:0;\r\n  transform:translateY(24px) scale(0.96);\r\n}\r\n\r\n.ols-mcq-screen.show{\r\n  animation:olsMcqScreenEnter 1s ease forwards;\r\n}\r\n\r\n@keyframes olsMcqScreenEnter{\r\n  from{opacity:0;transform:translateY(24px) scale(0.96);}\r\n  to{opacity:1;transform:translateY(0) scale(1);}\r\n}\r\n\r\n.mcq-question-area{\r\n  background:#eaf0ff;\r\n  padding:28px 30px 30px;\r\n  position:relative;\r\n  height:610px;\r\n}\r\n\r\n.mcq-question-lead{\r\n  margin:0 0 14px;\r\n  font-size:24px;\r\n  line-height:1.35;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-data-table{\r\n  border-collapse:collapse;\r\n  width:500px;\r\n  margin-bottom:8px;\r\n  font-size:21px;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-data-table th,\r\n.mcq-data-table td{\r\n  border:1.5px solid #c9ced8;\r\n  padding:12px 18px;\r\n  text-align:center;\r\n}\r\n\r\n.mcq-data-table th{\r\n  background:#f2f2f2;\r\n  font-weight:700;\r\n}\r\n\r\n.mcq-data-table td{\r\n  background:#eaf0ff;\r\n}\r\n\r\n.mcq-question-main{\r\n  margin:6px 0 28px;\r\n  font-size:24px;\r\n  line-height:1.35;\r\n  color:#111827;\r\n}\r\n\r\n.mcq-options-wrap{\r\n  display:flex;\r\n  flex-direction:column;\r\n  gap:17px;\r\n  max-width:1200px;\r\n}\r\n\r\n.mcq-option-row{\r\n  display:flex;\r\n  align-items:center;\r\n  min-height:34px;\r\n  position:relative;\r\n}\r\n\r\n.mcq-radio{\r\n  width:28px;\r\n  height:28px;\r\n  border-radius:50%;\r\n  border:2px solid #6b7280;\r\n  margin-right:16px;\r\n  background:transparent;\r\n  position:relative;\r\n  flex:0 0 auto;\r\n}\r\n\r\n.mcq-radio::after{\r\n  content:\"\";\r\n  position:absolute;\r\n  inset:5px;\r\n  border-radius:50%;\r\n  background:#6b7280;\r\n  opacity:0;\r\n  transform:scale(0.4);\r\n  transition:opacity 0.25s ease,transform 0.25s ease;\r\n}\r\n\r\n.mcq-option-row.selected .mcq-radio::after{\r\n  opacity:1;\r\n  transform:scale(1);\r\n}\r\n\r\n.mcq-radio-ripple{\r\n  position:absolute;\r\n  left:14px;\r\n  top:50%;\r\n  width:28px;\r\n  height:28px;\r\n  border-radius:50%;\r\n  border:2px solid rgba(28,36,75,0.28);\r\n  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class=\"ols-mcq-scale-wrap\">\r\n        <main id=\"mcqScreen\" class=\"ols-mcq-screen\">\r\n          <section class=\"mcq-question-area\">\r\n            <p class=\"mcq-question-lead\">A compound contains carbon, hydrogen and oxygen only. Its percentage composition by mass is shown.<\/p>\r\n\r\n            <table class=\"mcq-data-table\">\r\n              <thead>\r\n                <tr>\r\n                  <th>Element<\/th>\r\n                  <th>Percentage by mass<\/th>\r\n                <\/tr>\r\n              <\/thead>\r\n              <tbody>\r\n                <tr><td>C<\/td><td>40.0%<\/td><\/tr>\r\n                <tr><td>H<\/td><td>6.7%<\/td><\/tr>\r\n                <tr><td>O<\/td><td>53.3%<\/td><\/tr>\r\n              <\/tbody>\r\n            <\/table>\r\n\r\n            <p class=\"mcq-question-main\">What is the empirical formula of the compound?<\/p>\r\n\r\n            <div class=\"mcq-options-wrap\">\r\n              <div id=\"mcqWrongOption\" class=\"mcq-option-row\">\r\n                <span class=\"mcq-radio\"><\/span>\r\n                <span class=\"mcq-radio-ripple\"><\/span>\r\n                <span class=\"mcq-option-label\">C<sub>2<\/sub>H<sub>4<\/sub>O<sub>2<\/sub><\/span>\r\n\r\n                <span id=\"mcqSpecificFeedback\" class=\"mcq-specific-feedback\">\r\n                  <span id=\"mcqCrossIcon\" class=\"mcq-cross-icon\">\u00d7<\/span>\r\n                  <span class=\"mcq-specific-feedback-text\">\r\n                    <span id=\"mcqSpecificText\"><\/span><span id=\"mcqSpecificCursor\" class=\"cursor mcq-specific-cursor\" style=\"display:none;\"><\/span>\r\n                  <\/span>\r\n                <\/span>\r\n              <\/div>\r\n\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">CH<sub>2<\/sub>O<\/span><\/div>\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">CHO<\/span><\/div>\r\n              <div class=\"mcq-option-row\"><span class=\"mcq-radio\"><\/span><span class=\"mcq-radio-ripple\"><\/span><span class=\"mcq-option-label\">CH<sub>4<\/sub>O<\/span><\/div>\r\n            <\/div>\r\n\r\n            <button id=\"mcqSubmitButton\" class=\"mcq-submit-button\">Submit answer<\/button>\r\n          <\/section>\r\n\r\n          <section id=\"mcqGeneralFeedback\" class=\"mcq-general-feedback\">\r\n            <span id=\"mcqGeneralText\"><\/span><span id=\"mcqGeneralCursor\" class=\"cursor mcq-general-cursor\" style=\"display:none;\"><\/span>\r\n          <\/section>\r\n        <\/main>\r\n      <\/div>\r\n    <\/div>\r\n  <\/section>\r\n\r\n  <section id=\"sceneSaq\" class=\"ols-scene\">\r\n    <div class=\"ols-saq-stage\">\r\n      <div id=\"saqIntro\" class=\"ols-saq-intro\">\r\n        <div class=\"ols-saq-intro-title-wrap\">\r\n          <h1 class=\"ols-saq-intro-title\">\r\n            <span id=\"saqIntroTitleText\"><\/span><span id=\"saqIntroTitleCursor\" class=\"ols-title-cursor\"><\/span>\r\n          <\/h1>\r\n        <\/div>\r\n      <\/div>\r\n\r\n      <div class=\"ols-saq-scale-wrap\">\r\n        <main id=\"saqScreen\" class=\"ols-saq-screen\">\r\n          <section class=\"saq-question-area\">\r\n            <div class=\"saq-question-text\">\r\n              <strong>(ii)<\/strong>&nbsp;&nbsp; A student reacts magnesium with hydrochloric acid and collects hydrogen gas.<br>\r\n              Explain how the volume of hydrogen can be used to calculate the amount of magnesium that reacted.\r\n            <\/div>\r\n\r\n            <div class=\"saq-student-box\">\r\n              <span id=\"saqStudentText\"><\/span><span id=\"saqStudentCursor\" class=\"cursor\"><\/span>\r\n            <\/div>\r\n          <\/section>\r\n\r\n          <section id=\"saqTeacherFeedback\" class=\"saq-teacher-feedback\">\r\n            <span id=\"saqTeacherText\"><\/span><span id=\"saqTeacherCursor\" class=\"cursor saq-teacher-cursor\" style=\"display:none;\"><\/span>\r\n          <\/section>\r\n        <\/main>\r\n      <\/div>\r\n    <\/div>\r\n  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   <h2>Related Topic 5 Pages<\/h2>\n        <p>Use these pages to connect calculations with solutions and gases to mole calculations, empirical formulae, equations and amount of substance revision.<\/p>\n\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\/mole-calculations\/\">Mole Calculations<\/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\/mole-calculations\/calculations-involving-moles\/\">Calculations involving Moles<\/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\/mole-calculations\/calculations-using-reacting-masses\/\">Calculations using Reacting Masses<\/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\/empirical-and-molecular-formulae\/\">Empirical and Molecular Formulae<\/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\/\">Topic 5 Overview<\/a>\n        <\/div>\n      <\/section>\n\n      <section class=\"ols-attribution-card\">\n        <p><strong>Copyright notice:<\/strong> This revision page, including its written explanations, layout and teaching sequence, is produced for Online Learning System by Dr. Mohammed Al-Fatah. It is intended for student revision and may not be copied, redistributed or republished without permission.<\/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\/calculations-with-solutions-and-gases\/#webpage\",\n            \"url\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/\",\n            \"name\": \"Calculations with Solutions and Gases - Edexcel A Level Chemistry\",\n            \"description\": \"Edexcel A Level Chemistry Topic 5 landing page for calculations with solutions and gases, including molar volume calculations, concentrations of solutions and titration calculations.\",\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\": \"Molar volume calculations\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Concentrations of solutions\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Titration calculations\"\n              },\n              {\n                \"@type\": \"Thing\",\n                \"name\": \"Amount of substance calculations\"\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\/calculations-with-solutions-and-gases\/#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\": \"Calculations with Solutions and Gases\",\n                \"item\": \"https:\/\/www.onlinelearningsystem.net\/xyz\/revision-notes\/a-level-chemistry\/edexcel\/topic-5-formulae-equations-and-amounts-of-substance\/calculations-with-solutions-and-gases\/\"\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 \/ Calculations with Solutions and Gases Calculations with Solutions and Gases Use this landing page to move quickly between the key quantitative chemistry pages for solutions and gases in Edexcel Topic 5. 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