<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background: #f8fafc;
      color: #1e293b;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 16px 12px;
      user-select: none;
    }

    /* Top Control Bar */
    .controls {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 8px;
      width: 100%;
      max-width: 500px;
    }

    .control-header {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      font-size: 15px;
      font-weight: 700;
      color: #334155;
    }

    .mult-pill {
      background: #0ea5e9;
      color: #fff;
      padding: 2px 10px;
      border-radius: 12px;
      font-size: 14px;
      font-weight: 700;
      min-width: 38px;
      text-align: center;
    }

    .btn-group {
      display: flex;
      width: 100%;
      gap: 6px;
    }

    .btn-step {
      flex: 1;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #475569;
      padding: 8px 0;
      border-radius: 8px;
      font-size: 14px;
      font-weight: 700;
      cursor: pointer;
      box-shadow: 0 1px 2px rgba(0,0,0,0.05);
      transition: all 0.2s ease;
      text-align: center;
    }

    .btn-step.active {
      background: #0ea5e9;
      color: #ffffff;
      border-color: #0ea5e9;
      box-shadow: 0 2px 6px rgba(14, 165, 233, 0.35);
    }

    /* Comparison Columns */
    .chart-container {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 10px;
      width: 100%;
      max-width: 500px;
      height: 250px;
      margin-top: 10px;
    }

    .order-card {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 6px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      position: relative;
    }

    .card-title {
      font-size: 14px;
      font-weight: 750;
      text-align: center;
      line-height: 1.2;
    }

    .card-title sub {
      font-size: 11px;
    }

    /* Graph track & bar */
    .bar-track {
      flex: 1;
      width: 44px;
      background: #f1f5f9;
      border-radius: 6px;
      margin: 8px 0;
      display: flex;
      flex-direction: column;
      justify-content: flex-end;
      position: relative;
      overflow: hidden;
    }

    .bar {
      width: 100%;
      border-radius: 5px 5px 0 0;
      transition: height 0.4s cubic-bezier(0.34, 1.2, 0.64, 1);
      display: flex;
      align-items: flex-start;
      justify-content: center;
    }

    .rate-badge {
      font-size: 13px;
      font-weight: 800;
      text-align: center;
      padding: 4px 8px;
      border-radius: 6px;
      width: 100%;
      max-width: 72px;
      letter-spacing: -0.2px;
    }

    /* Distinct Colors */
    .order-0 .card-title { color: #7c3aed; }
    .order-0 .bar { background: linear-gradient(180deg, #8b5cf6, #7c3aed); }
    .order-0 .rate-badge { background: #f3e8ff; color: #6d28d9; }

    .order-1 .card-title { color: #2563eb; }
    .order-1 .bar { background: linear-gradient(180deg, #3b82f6, #2563eb); }
    .order-1 .rate-badge { background: #dbeafe; color: #1d4ed8; }

    .order-2 .card-title { color: #d97706; }
    .order-2 .bar { background: linear-gradient(180deg, #f59e0b, #d97706); }
    .order-2 .rate-badge { background: #fef3c7; color: #b45309; }

    /* Grid guidelines */
    .guideline {
      position: absolute;
      left: 0;
      right: 0;
      border-top: 1px dashed rgba(148, 163, 184, 0.3);
      pointer-events: none;
    }
  </style>
</head>
<body>

  <div class="controls">
    <div class="control-header">
      [A] Multiplier: <span id="multDisplay" class="mult-pill">1×</span>
    </div>
    <div class="btn-group">
      <button class="btn-step active" onclick="setConc(1)">1×</button>
      <button class="btn-step" onclick="setConc(2)">2×</button>
      <button class="btn-step" onclick="setConc(3)">3×</button>
      <button class="btn-step" onclick="setConc(4)">4×</button>
    </div>
  </div>

  <div class="chart-container">
    
    <div class="order-card order-0">
      <div class="card-title">Zero<br>[A]⁰</div>
      <div class="bar-track">
        <div class="guideline" style="bottom: 6.25%;"></div>
        <div class="bar" id="bar0" style="height: 6.25%;"></div>
      </div>
      <div class="rate-badge" id="rate0">1×</div>
    </div>

    
    <div class="order-card order-1">
      <div class="card-title">First<br>[A]¹</div>
      <div class="bar-track">
        <div class="guideline" style="bottom: 25%;"></div>
        <div class="bar" id="bar1" style="height: 6.25%;"></div>
      </div>
      <div class="rate-badge" id="rate1">1×</div>
    </div>

    
    <div class="order-card order-2">
      <div class="card-title">Second<br>[A]²</div>
      <div class="bar-track">
        <div class="guideline" style="bottom: 100%;"></div>
        <div class="bar" id="bar2" style="height: 6.25%;"></div>
      </div>
      <div class="rate-badge" id="rate2">1×</div>
    </div>
  </div>

  <script>
    const MAX_RATE = 16;
    const buttons = document.querySelectorAll('.btn-step');
    const multDisplay = document.getElementById('multDisplay');
    const bar0 = document.getElementById('bar0');
    const bar1 = document.getElementById('bar1');
    const bar2 = document.getElementById('bar2');
    const rate0 = document.getElementById('rate0');
    const rate1 = document.getElementById('rate1');
    const rate2 = document.getElementById('rate2');

    function setConc(m) {
      buttons.forEach((btn, idx) => {
        btn.classList.toggle('active', idx + 1 === m);
      });

      multDisplay.textContent = m + '×';

      // Zero order: 1
      const r0 = 1;
      // First order: m
      const r1 = m;
      // Second order: m^2
      const r2 = m * m;

      // Update Bar Heights (minimum height base ensures clean visibility)
      bar0.style.height = Math.max(6, (r0 / MAX_RATE) * 100) + '%';
      bar1.style.height = Math.max(6, (r1 / MAX_RATE) * 100) + '%';
      bar2.style.height = Math.max(6, (r2 / MAX_RATE) * 100) + '%';

      // Update Rate Labels
      rate0.textContent = r0 + '×';
      rate1.textContent = r1 + '×';
      rate2.textContent = r2 + '×';
    }
  </script>
</body>
</html>

Determining Reaction Orders from Initial Rate Experiments

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 100%;
    }

    .rxn-header {
      font-size: 15px;
      font-weight: 700;
      color: #334155;
      margin-bottom: 12px;
      letter-spacing: 0.5px;
    }

    .btn-group {
      display: flex;
      gap: 8px;
      margin-bottom: 14px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .btn {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 20px;
      padding: 6px 14px;
      font-size: 13px;
      font-weight: 600;
      color: #475569;
      cursor: pointer;
      transition: all 0.25s ease;
      outline: none;
    }

    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
      box-shadow: 0 2px 6px rgba(2, 132, 199, 0.25);
    }

    .matrix {
      display: flex;
      flex-direction: column;
      gap: 8px;
      width: 100%;
      max-width: 480px;
    }

    .card-row {
      display: grid;
      grid-template-columns: 74px 1fr 1fr 1.15fr;
      gap: 6px;
      align-items: center;
      background: #f8fafc;
      border: 1.5px solid #e2e8f0;
      border-radius: 8px;
      padding: 8px 10px;
      transition: all 0.25s ease;
      position: relative;
    }

    .card-row.dimmed {
      opacity: 0.35;
      filter: grayscale(40%);
    }

    .card-row.selected {
      border-color: #94a3b8;
      background: #ffffff;
      box-shadow: 0 2px 8px rgba(0,0,0,0.04);
    }

    .trial-id {
      font-size: 13px;
      font-weight: 800;
      color: #475569;
    }

    .val-cell {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      padding: 4px 2px;
      border-radius: 6px;
      transition: all 0.25s ease;
      border: 1px solid transparent;
      position: relative;
    }

    .lbl {
      font-size: 10px;
      font-weight: 700;
      color: #64748b;
      margin-bottom: 2px;
    }

    .num {
      font-size: 13px;
      font-weight: 700;
      font-family: monospace;
      color: #0f172a;
    }

    /* Comparison Badges & Highlights */
    .highlight-double {
      background: #e0f2fe;
      border-color: #38bdf8;
      color: #0369a1;
    }
    .highlight-double .num { color: #0284c7; }

    .highlight-quad {
      background: #fef3c7;
      border-color: #f59e0b;
      color: #b45309;
    }
    .highlight-quad .num { color: #d97706; }

    .highlight-const {
      background: #f1f5f9;
      border-color: #cbd5e1;
      opacity: 0.75;
    }

    .tag {
      position: absolute;
      top: -9px;
      right: 2px;
      font-size: 9px;
      font-weight: 800;
      padding: 1px 5px;
      border-radius: 10px;
      letter-spacing: 0.3px;
      animation: pop 0.25s ease;
    }
    .tag-blue { background: #0284c7; color: #fff; }
    .tag-orange { background: #d97706; color: #fff; }
    .tag-gray { background: #64748b; color: #fff; }

    @keyframes pop {
      0% { transform: scale(0.6); opacity: 0; }
      100% { transform: scale(1); opacity: 1; }
    }

    .summary-box {
      margin-top: 12px;
      padding: 8px 14px;
      border-radius: 8px;
      font-size: 13px;
      font-weight: 700;
      text-align: center;
      min-height: 38px;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all 0.25s ease;
      width: 100%;
      max-width: 480px;
      border: 1.5px solid transparent;
    }
    .summary-idle {
      background: #f8fafc;
      color: #64748b;
      border-color: #e2e8f0;
    }
    .summary-no {
      background: #e0f2fe;
      color: #0369a1;
      border-color: #7dd3fc;
    }
    .summary-o2 {
      background: #fef3c7;
      color: #92400e;
      border-color: #fcd34d;
    }
  </style>
</head>
<body>

  <div class="rxn-header">2NO(g) + O₂(g) → 2NO₂(g)</div>

  <div class="btn-group">
    <button class="btn active" id="btn-all" onclick="setMode('all')">All Trials</button>
    <button class="btn" id="btn-12" onclick="setMode('1-2')">Compare 1 & 2</button>
    <button class="btn" id="btn-13" onclick="setMode('1-3')">Compare 1 & 3</button>
  </div>

  <div class="matrix">
    
    <div class="card-row" id="row-1">
      <div class="trial-id">Trial 1</div>
      <div class="val-cell" id="c1-no">
        <div class="lbl">[NO]</div>
        <div class="num">0.010</div>
      </div>
      <div class="val-cell" id="c1-o2">
        <div class="lbl">[O₂]</div>
        <div class="num">0.010</div>
      </div>
      <div class="val-cell" id="c1-rate">
        <div class="lbl">Rate (M/s)</div>
        <div class="num">0.022</div>
      </div>
    </div>

    
    <div class="card-row" id="row-2">
      <div class="trial-id">Trial 2</div>
      <div class="val-cell" id="c2-no">
        <div class="lbl">[NO]</div>
        <div class="num">0.020</div>
      </div>
      <div class="val-cell" id="c2-o2">
        <div class="lbl">[O₂]</div>
        <div class="num">0.010</div>
      </div>
      <div class="val-cell" id="c2-rate">
        <div class="lbl">Rate (M/s)</div>
        <div class="num">0.088</div>
      </div>
    </div>

    
    <div class="card-row" id="row-3">
      <div class="trial-id">Trial 3</div>
      <div class="val-cell" id="c3-no">
        <div class="lbl">[NO]</div>
        <div class="num">0.010</div>
      </div>
      <div class="val-cell" id="c3-o2">
        <div class="lbl">[O₂]</div>
        <div class="num">0.020</div>
      </div>
      <div class="val-cell" id="c3-rate">
        <div class="lbl">Rate (M/s)</div>
        <div class="num">0.044</div>
      </div>
    </div>
  </div>

  <div class="summary-box summary-idle" id="summary">
    Select a comparison
  </div>

  <script>
    function clearStyles() {
      ['row-1', 'row-2', 'row-3'].forEach(id => {
        const el = document.getElementById(id);
        el.className = 'card-row';
      });
      document.querySelectorAll('.val-cell').forEach(el => {
        el.className = 'val-cell';
        const tag = el.querySelector('.tag');
        if (tag) tag.remove();
      });
      ['btn-all', 'btn-12', 'btn-13'].forEach(id => {
        document.getElementById(id).classList.remove('active');
      });
    }

    function addTag(cellId, text, type) {
      const cell = document.getElementById(cellId);
      const tag = document.createElement('div');
      tag.className = 'tag ' + type;
      tag.textContent = text;
      cell.appendChild(tag);
    }

    function setMode(mode) {
      clearStyles();
      const sum = document.getElementById('summary');

      if (mode === 'all') {
        document.getElementById('btn-all').classList.add('active');
        sum.className = 'summary-box summary-idle';
        sum.textContent = 'Select a comparison';
      } else if (mode === '1-2') {
        document.getElementById('btn-12').classList.add('active');
        document.getElementById('row-1').classList.add('selected');
        document.getElementById('row-2').classList.add('selected');
        document.getElementById('row-3').classList.add('dimmed');

        // [NO] doubles
        document.getElementById('c1-no').classList.add('highlight-double');
        document.getElementById('c2-no').classList.add('highlight-double');
        addTag('c2-no', '×2', 'tag-blue');

        // [O2] constant
        document.getElementById('c1-o2').classList.add('highlight-const');
        document.getElementById('c2-o2').classList.add('highlight-const');
        addTag('c2-o2', 'const', 'tag-gray');

        // Rate quadruples
        document.getElementById('c1-rate').classList.add('highlight-quad');
        document.getElementById('c2-rate').classList.add('highlight-quad');
        addTag('c2-rate', '×4', 'tag-orange');

        sum.className = 'summary-box summary-no';
        sum.innerHTML = '[NO] ×2 → Rate ×4 (2²) ⇒ Order = 2';
      } else if (mode === '1-3') {
        document.getElementById('btn-13').classList.add('active');
        document.getElementById('row-1').classList.add('selected');
        document.getElementById('row-3').classList.add('selected');
        document.getElementById('row-2').classList.add('dimmed');

        // [NO] constant
        document.getElementById('c1-no').classList.add('highlight-const');
        document.getElementById('c3-no').classList.add('highlight-const');
        addTag('c3-no', 'const', 'tag-gray');

        // [O2] doubles
        document.getElementById('c1-o2').classList.add('highlight-double');
        document.getElementById('c3-o2').classList.add('highlight-double');
        addTag('c3-o2', '×2', 'tag-blue');

        // Rate doubles
        document.getElementById('c1-rate').classList.add('highlight-double');
        document.getElementById('c3-rate').classList.add('highlight-double');
        addTag('c3-rate', '×2', 'tag-blue');

        sum.className = 'summary-box summary-o2';
        sum.innerHTML = '[O₂] ×2 → Rate ×2 (2¹) ⇒ Order = 1';
      }
    }
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #ffffff;
      color: #1e2945;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      user-select: none;
    }

    /* Top Step Selector */
    .step-nav {
      display: flex;
      gap: 6px;
      width: 100%;
      max-width: 480px;
      margin-bottom: 12px;
    }
    .step-btn {
      flex: 1;
      border: 1px solid #e2e8f0;
      background: #f8fafc;
      border-radius: 8px;
      padding: 8px 4px;
      font-size: 13px;
      font-weight: 600;
      color: #64748b;
      cursor: pointer;
      text-align: center;
      transition: all 0.25s ease;
    }
    .step-btn.active {
      background: #eff6ff;
      border-color: #3b82f6;
      color: #1d4ed8;
      box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.15);
    }

    /* Step Display Area */
    .stage {
      position: relative;
      width: 100%;
      max-width: 480px;
      height: 250px;
      overflow: hidden;
    }
    .step-card {
      position: absolute;
      inset: 0;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      opacity: 0;
      pointer-events: none;
      transform: translateY(8px);
      transition: opacity 0.35s ease, transform 0.35s ease;
      gap: 14px;
    }
    .step-card.active {
      opacity: 1;
      pointer-events: auto;
      transform: translateY(0);
    }

    /* Math & Fraction Styles */
    .math-row {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-size: 18px;
      font-weight: 600;
      color: #0f172a;
    }
    .frac {
      display: inline-flex;
      flex-direction: column;
      vertical-align: middle;
      text-align: center;
      padding: 0 4px;
    }
    .num {
      padding-bottom: 3px;
      border-bottom: 2px solid #334155;
    }
    .den {
      padding-top: 3px;
    }

    /* Color Tokens */
    .rate { color: #2563eb; }
    .no { color: #7c3aed; }
    .o2 { color: #059669; }
    .k-val { color: #d97706; font-weight: 700; }
    .unit-cancel {
      position: relative;
      display: inline-block;
    }
    .unit-cancel::after {
      content: "";
      position: absolute;
      left: -2px;
      top: 50%;
      width: calc(100% + 4px);
      height: 2px;
      background: #ef4444;
      transform: rotate(-20deg);
    }

    /* Visual Highlighting Badges */
    .badge-box {
      display: flex;
      align-items: center;
      gap: 8px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 600;
    }
    .order-tag {
      background: #fef3c7;
      color: #92400e;
      padding: 2px 8px;
      border-radius: 12px;
      border: 1px solid #fde68a;
    }
    .arrow-down {
      font-size: 16px;
      color: #94a3b8;
    }

    /* Controls */
    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      margin-top: 8px;
      width: 100%;
    }
    .ctrl-btn {
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      color: #334155;
      padding: 6px 14px;
      border-radius: 6px;
      font-size: 13px;
      font-weight: 600;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      transition: background 0.2s ease;
    }
    .ctrl-btn:hover {
      background: #e2e8f0;
    }
    .progress-bar {
      width: 100%;
      max-width: 480px;
      height: 3px;
      background: #f1f5f9;
      border-radius: 2px;
      overflow: hidden;
      margin-top: 6px;
    }
    .progress-fill {
      height: 100%;
      width: 33.33%;
      background: #3b82f6;
      transition: width 0.3s ease;
    }
  </style>
</head>
<body>

  
  <div class="step-nav">
    <button class="step-btn active" onclick="goToStep(0)">1. Isolate k</button>
    <button class="step-btn" onclick="goToStep(1)">2. Substitute</button>
    <button class="step-btn" onclick="goToStep(2)">3. Unit Algebra</button>
  </div>

  
  <div class="stage">

    
    <div class="step-card active" id="card-0">
      <div class="math-row">
        <span class="rate">Rate</span> = <span>k</span> [<span class="no">NO</span>]<sup>2</sup> [<span class="o2">O<sub>2</sub></span>]<sup>1</sup>
      </div>
      <div class="arrow-down">↓</div>
      <div class="math-row">
        <span>k</span> = 
        <div class="frac">
          <span class="num rate">Rate</span>
          <span class="den">[<span class="no">NO</span>]<sup>2</sup> [<span class="o2">O<sub>2</sub></span>]</span>
        </div>
      </div>
      <div class="badge-box">
        <span>Overall Order (n):</span>
        <span class="order-tag">2 + 1 = 3</span>
      </div>
    </div>

    
    <div class="step-card" id="card-1">
      <div class="math-row" style="font-size: 16px;">
        <span>k</span> = 
        <div class="frac">
          <span class="num rate">0.022 M s<sup>−1</sup></span>
          <span class="den">(<span class="no">0.010 M</span>)<sup>2</sup> (<span class="o2">0.010 M</span>)</span>
        </div>
      </div>
      <div class="arrow-down">↓</div>
      <div class="math-row" style="font-size: 16px;">
        <span>k</span> = 
        <div class="frac">
          <span class="num rate">0.022</span>
          <span class="den">1.0 × 10<sup>−6</sup></span>
        </div>
        = <span class="k-val">2.2 × 10<sup>4</sup></span>
      </div>
      <div class="badge-box">
        <span>Magnitude:</span>
        <span class="order-tag" style="background:#eff6ff; color:#1e40af; border-color:#bfdbfe;">22,000</span>
      </div>
    </div>

    
    <div class="step-card" id="card-2">
      <div class="math-row" style="font-size: 16px;">
        <div class="frac">
          <span class="num"><span class="unit-cancel">M</span> · s<sup>−1</sup></span>
          <span class="den"><span class="unit-cancel">M</span> · M<sup>2</sup></span>
        </div>
        = 
        <div class="frac">
          <span class="num">s<sup>−1</sup></span>
          <span class="den">M<sup>2</sup></span>
        </div>
        = <span class="k-val">M<sup>−2</sup> s<sup>−1</sup></span>
      </div>
      <div class="arrow-down">↓</div>
      <div class="badge-box">
        <span>Formula:</span>
        <span class="order-tag">M<sup>1 − n</sup> s<sup>−1</sup></span>
        <span>(n = 3)</span>
      </div>
      <div class="badge-box" style="background:#f0fdf4; border-color:#bbf7d0; color:#166534;">
        <span>Equivalent: L<sup>2</sup> mol<sup>−2</sup> s<sup>−1</sup></span>
      </div>
    </div>

  </div>

  
  <div class="progress-bar">
    <div class="progress-fill" id="progress"></div>
  </div>

  
  <div class="controls">
    <button class="ctrl-btn" onclick="prevStep()">← Back</button>
    <button class="ctrl-btn" id="playBtn" onclick="togglePlay()">⏸ Pause</button>
    <button class="ctrl-btn" onclick="nextStep()">Next →</button>
  </div>

  <script>
    let current = 0;
    const totalSteps = 3;
    let isPlaying = true;
    let timer = null;

    const cards = [document.getElementById('card-0'), document.getElementById('card-1'), document.getElementById('card-2')];
    const buttons = document.querySelectorAll('.step-btn');
    const progress = document.getElementById('progress');
    const playBtn = document.getElementById('playBtn');

    function updateView() {
      cards.forEach((card, idx) => {
        card.classList.toggle('active', idx === current);
        buttons[idx].classList.toggle('active', idx === current);
      });
      progress.style.width = ((current + 1) / totalSteps * 100) + '%';
    }

    function goToStep(index) {
      current = index;
      updateView();
      if (isPlaying) resetTimer();
    }

    function nextStep() {
      current = (current + 1) % totalSteps;
      updateView();
      if (isPlaying) resetTimer();
    }

    function prevStep() {
      current = (current - 1 + totalSteps) % totalSteps;
      updateView();
      if (isPlaying) resetTimer();
    }

    function resetTimer() {
      clearInterval(timer);
      if (isPlaying) {
        timer = setInterval(nextStep, 4500);
      }
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      playBtn.textContent = isPlaying ? '⏸ Pause' : '▶ Play';
      if (isPlaying) {
        resetTimer();
      } else {
        clearInterval(timer);
      }
    }

    // Initialize auto-play
    resetTimer();
  </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      -webkit-tap-highlight-color: transparent;
    }

    body {
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      background: #ffffff;
      color: #1e293b;
      padding: 16px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-start;
      gap: 14px;
      user-select: none;
    }

    /* Equation Display */
    .equation-bar {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      font-size: 28px;
      font-weight: 700;
      padding: 12px 20px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 12px;
      width: 100%;
      max-width: 580px;
      box-shadow: 0 1px 3px rgba(0,0,0,0.03);
    }

    .eq-token {
      cursor: pointer;
      padding: 2px 6px;
      border-radius: 6px;
      transition: all 0.2s ease;
      display: inline-flex;
      align-items: baseline;
      border: 1px solid transparent;
    }

    .eq-token:hover, .eq-token.active {
      background: #ffffff;
      box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    }

    /* Token Accents */
    .token-rate { color: #8b5cf6; }
    .token-rate.active { border-color: #8b5cf6; }

    .token-k { color: #0284c7; }
    .token-k.active { border-color: #0284c7; }

    .token-reactants { color: #334155; }
    .token-reactants.active { border-color: #64748b; }

    .token-orders { color: #059669; }
    .token-orders.active { border-color: #059669; }

    .sup-val {
      font-size: 19px;
      transform: translateY(-8px);
      margin-left: 1px;
    }

    .eq-op {
      color: #94a3b8;
      font-weight: 400;
    }

    /* Interactive Cards Grid */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 10px;
      width: 100%;
      max-width: 580px;
    }

    .card-btn {
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 10px 12px;
      cursor: pointer;
      text-align: left;
      transition: border-color 0.2s ease, box-shadow 0.2s ease, background-color 0.2s ease;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }

    .card-btn:hover {
      background: #f8fafc;
    }

    .card-btn.active {
      background: #ffffff;
      box-shadow: 0 4px 12px rgba(0,0,0,0.06);
    }

    .card-btn.c-rate.active { border-color: #8b5cf6; }
    .card-btn.c-k.active { border-color: #0284c7; }
    .card-btn.c-conc.active { border-color: #64748b; }
    .card-btn.c-ord.active { border-color: #059669; }

    .card-head {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .card-sym {
      font-size: 17px;
      font-weight: 700;
    }

    .card-badge {
      font-size: 11px;
      font-weight: 600;
      padding: 2px 6px;
      border-radius: 4px;
      text-transform: uppercase;
      letter-spacing: 0.3px;
    }

    .b-rate { background: #f3e8ff; color: #7c3aed; }
    .b-k { background: #e0f2fe; color: #0284c7; }
    .b-conc { background: #f1f5f9; color: #475569; }
    .b-ord { background: #d1fae5; color: #059669; }

    .card-title {
      font-size: 13px;
      font-weight: 600;
      color: #1e293b;
    }

    .card-sub {
      font-size: 12px;
      color: #64748b;
    }

    /* Demonstration Panel */
    .demo-panel {
      width: 100%;
      max-width: 580px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 10px;
      padding: 12px 14px;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .demo-title-row {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .demo-label {
      font-size: 13px;
      font-weight: 700;
      color: #334155;
    }

    .demo-action {
      display: flex;
      gap: 6px;
    }

    .toggle-pill {
      font-size: 12px;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 6px;
      border: 1px solid #cbd5e1;
      background: #ffffff;
      color: #475569;
      cursor: pointer;
      transition: all 0.15s ease;
    }

    .toggle-pill.selected {
      background: #059669;
      border-color: #059669;
      color: #ffffff;
    }

    /* Multiplier Visual Row */
    .visual-calc {
      display: flex;
      align-items: center;
      justify-content: space-around;
      background: #ffffff;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      padding: 10px;
      font-size: 14px;
      font-weight: 600;
    }

    .calc-step {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 2px;
    }

    .step-sub {
      font-size: 11px;
      font-weight: 500;
      color: #64748b;
    }

    .arrow-op {
      font-size: 18px;
      color: #94a3b8;
    }

    .impact-val {
      font-size: 17px;
      font-weight: 800;
      color: #059669;
    }

    @media (max-width: 420px) {
      .equation-bar { font-size: 22px; padding: 10px 14px; }
      .sup-val { font-size: 15px; }
      .cards-grid { grid-template-columns: 1fr; }
    }
  </style>
</head>
<body>

  
  <div class="equation-bar">
    <div class="eq-token token-rate active" id="tok-rate" onclick="selectComponent('rate')">Rate</div>
    <span class="eq-op">=</span>
    <div class="eq-token token-k" id="tok-k" onclick="selectComponent('k')">k</div>
    <div class="eq-token token-reactants" id="tok-conc" onclick="selectComponent('conc')">
      [A]<span class="sup-val token-orders" id="tok-m">m</span>[B]<span class="sup-val token-orders" id="tok-n">n</span>
    </div>
  </div>

  
  <div class="cards-grid">
    <div class="card-btn c-rate active" id="card-rate" onclick="selectComponent('rate')">
      <div class="card-head">
        <span class="card-sym token-rate">Rate</span>
        <span class="card-badge b-rate">Speed</span>
      </div>
      <div class="card-title">Reaction Speed</div>
      <div class="card-sub">Measured in M / s</div>
    </div>

    <div class="card-btn c-k" id="card-k" onclick="selectComponent('k')">
      <div class="card-head">
        <span class="card-sym token-k">k</span>
        <span class="card-badge b-k">Constant</span>
      </div>
      <div class="card-title">Rate Constant</div>
      <div class="card-sub">Specific to Temperature</div>
    </div>

    <div class="card-btn c-conc" id="card-conc" onclick="selectComponent('conc')">
      <div class="card-head">
        <span class="card-sym token-reactants">[A], [B]</span>
        <span class="card-badge b-conc">Molarity</span>
      </div>
      <div class="card-title">Concentrations</div>
      <div class="card-sub">Reactants in mol / L</div>
    </div>

    <div class="card-btn c-ord" id="card-ord" onclick="selectComponent('ord')">
      <div class="card-head">
        <span class="card-sym token-orders">m, n</span>
        <span class="card-badge b-ord">Order</span>
      </div>
      <div class="card-title">Reaction Orders</div>
      <div class="card-sub">Found Experimentally</div>
    </div>
  </div>

  
  <div class="demo-panel">
    <div class="demo-title-row">
      <span class="demo-label">Effect of Order (<span style="color:#059669;">m</span>) if [A] doubles (2×):</span>
      <div class="demo-action">
        <button class="toggle-pill" id="btn-m0" onclick="setOrder(0)">m = 0</button>
        <button class="toggle-pill selected" id="btn-m1" onclick="setOrder(1)">m = 1</button>
        <button class="toggle-pill" id="btn-m2" onclick="setOrder(2)">m = 2</button>
      </div>
    </div>

    <div class="visual-calc">
      <div class="calc-step">
        <span>2× [A]</span>
        <span class="step-sub">Concentration</span>
      </div>
      <span class="arrow-op">→</span>
      <div class="calc-step">
        <span id="math-exp">2¹</span>
        <span class="step-sub">Factor (2ᵐ)</span>
      </div>
      <span class="arrow-op">→</span>
      <div class="calc-step">
        <span class="impact-val" id="impact-res">2× Rate</span>
        <span class="step-sub" id="impact-desc">Linear change</span>
      </div>
    </div>
  </div>

  <script>
    const tokens = {
      rate: document.getElementById('tok-rate'),
      k: document.getElementById('tok-k'),
      conc: document.getElementById('tok-conc'),
      ord: [document.getElementById('tok-m'), document.getElementById('tok-n')]
    };

    const cards = {
      rate: document.getElementById('card-rate'),
      k: document.getElementById('card-k'),
      conc: document.getElementById('card-conc'),
      ord: document.getElementById('card-ord')
    };

    function selectComponent(type) {
      // Clear token actives
      Object.keys(tokens).forEach(k => {
        if (Array.isArray(tokens[k])) {
          tokens[k].forEach(el => el.classList.remove('active'));
        } else {
          tokens[k].classList.remove('active');
        }
      });

      // Clear card actives
      Object.values(cards).forEach(c => c.classList.remove('active'));

      // Set active
      if (type === 'ord') {
        tokens.ord.forEach(el => el.classList.add('active'));
      } else {
        tokens[type].classList.add('active');
      }
      cards[type].classList.add('active');
    }

    const orderData = {
      0: { exp: '2⁰ = 1', res: '1× (No Change)', desc: 'Zero Order: unaffected' },
      1: { exp: '2¹ = 2', res: '2× Rate', desc: 'First Order: doubles' },
      2: { exp: '2² = 4', res: '4× Rate', desc: 'Second Order: quadruples' }
    };

    function setOrder(m) {
      selectComponent('ord');
      [0, 1, 2].forEach(i => {
        const btn = document.getElementById('btn-m' + i);
        if (i === m) {
          btn.classList.add('selected');
        } else {
          btn.classList.remove('selected');
        }
      });

      const d = orderData[m];
      document.getElementById('math-exp').textContent = d.exp;
      document.getElementById('impact-res').textContent = d.res;
      document.getElementById('impact-desc').textContent = d.desc;
    }
  </script>
</body>
</html>

OGS.13.CH.5

Aligned learning resources

Related diagrams