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  <title>Filtration vs Crystallisation</title>
  <style>
    * {
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      color: #1e2945;
      padding: 10px 12px;
      display: flex;
      justify-content: center;
      align-items: flex-start;
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    .grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
      width: 100%;
      max-width: 680px;
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    @media (max-width: 540px) {
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        grid-template-columns: 1fr;
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    .panel {
      display: flex;
      flex-direction: column;
      align-items: center;
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      font-weight: 700;
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      letter-spacing: 0.5px;
      text-align: center;
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      width: 100%;
      max-width: 260px;
      position: relative;
      display: flex;
      justify-content: center;
      align-items: center;
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    svg {
      width: 100%;
      height: auto;
      display: block;
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    .controls {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      margin-top: 8px;
      min-height: 32px;
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    .btn {
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      color: #1e2945;
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      font-size: 12px;
      font-weight: 700;
      border-radius: 6px;
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      display: inline-flex;
      align-items: center;
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    .btn:hover {
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    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
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    .stage-pill {
      font-size: 12px;
      font-weight: 700;
      color: #1e2945;
      background: #e2e8f0;
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      border-radius: 6px;
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      display: inline-flex;
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    .cryst-group {
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      opacity: 1;
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      opacity: 0;
      pointer-events: none;
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    @keyframes dripMotion {
      0% {
        transform: translateY(0);
        opacity: 0.95;
      }
      65% {
        transform: translateY(24px);
        opacity: 0.95;
      }
      100% {
        transform: translateY(30px);
        opacity: 0;
      }
    }
    .drip-animated {
      animation: dripMotion 2.2s infinite ease-in;
    }
  </style>
</head>
<body>

  <div class="grid">
    
    <div class="panel">
      <div class="panel-title">1. Filtration</div>
      <div class="svg-container">
        <svg viewBox="0 0 240 210" aria-label="Filtration apparatus diagram">
          
          <g transform="translate(42, 24) rotate(-35)">
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            <path d="M-15 -4 L 15 -4 L 15 8 L -15 8 Z" fill="#38bdf8" opacity="0.7"/>
            
            <circle cx="-5" cy="1" r="3.5" fill="#854d0e"/>
            <circle cx="6" cy="3" r="3.5" fill="#854d0e"/>
          </g>
          
          
          <path d="M 64 34 Q 82 48 94 62" fill="none" stroke="#0284c7" stroke-width="3" stroke-linecap="round"/>

          
          <polygon points="68,62 148,62 114,110 114,140 104,140 104,110" fill="#f8fafc" stroke="#475569" stroke-width="2"/>
          <polygon points="74,65 142,65 109,107" fill="#ffffff" stroke="#94a3b8" stroke-width="1.5"/>

          
          <circle cx="96" cy="82" r="4.5" fill="#854d0e"/>
          <circle cx="110" cy="87" r="5" fill="#854d0e"/>
          <circle cx="120" cy="79" r="4.5" fill="#854d0e"/>
          <text x="162" y="82" font-size="11" font-weight="700" fill="#1e2945">Residue</text>
          <line x1="158" y1="79" x2="126" y2="82" stroke="#1e2945" stroke-width="1.5" stroke-dasharray="2,2"/>

          
          <g class="drip-animated">
            <ellipse cx="109" cy="144" rx="2.5" ry="4" fill="#0284c7"/>
          </g>

          
          <polygon points="97,135 121,135 121,150 160,198 58,198 97,150" fill="none" stroke="#475569" stroke-width="2"/>
          
          <polygon points="66,192 152,192 140,170 78,170" fill="#38bdf8" opacity="0.75"/>
          
          
          <circle cx="88" cy="182" r="2.2" fill="#b45309"/>
          <circle cx="108" cy="186" r="2.2" fill="#b45309"/>
          <circle cx="128" cy="180" r="2.2" fill="#b45309"/>
          <circle cx="98" cy="174" r="2.2" fill="#b45309"/>
          <circle cx="118" cy="176" r="2.2" fill="#b45309"/>

          <text x="168" y="182" font-size="11" font-weight="700" fill="#1e2945">Filtrate</text>
          <line x1="164" y1="179" x2="140" y2="179" stroke="#1e2945" stroke-width="1.5" stroke-dasharray="2,2"/>
        </svg>
      </div>
      <div class="stage-pill">Separates Insoluble Solids</div>
    </div>

    
    <div class="panel">
      <div class="panel-title">2. Crystallisation</div>
      <div class="svg-container">
        <svg viewBox="0 0 240 210" id="crystSvg" aria-label="Crystallisation apparatus diagram">
          
          <g id="crystHeat" class="cryst-group">
            <text x="120" y="20" text-anchor="middle" font-size="12" font-weight="700" fill="#1e2945">Evaporate Solvent (Heat)</text>
            
            
            <path d="M100 58 Q 95 44 100 35" fill="none" stroke="#94a3b8" stroke-width="2" stroke-linecap="round"/>
            <path d="M120 53 Q 125 39 120 30" fill="none" stroke="#94a3b8" stroke-width="2" stroke-linecap="round"/>
            <path d="M140 58 Q 135 44 140 35" fill="none" stroke="#94a3b8" stroke-width="2" stroke-linecap="round"/>

            
            <path d="M62 78 Q 120 126 178 78 Z" fill="#ffffff" stroke="#475569" stroke-width="2"/>
            <path d="M72 83 Q 120 120 168 83 Z" fill="#38bdf8" opacity="0.8"/>

            
            <circle cx="98" cy="94" r="2.2" fill="#b45309"/>
            <circle cx="120" cy="98" r="2.2" fill="#b45309"/>
            <circle cx="142" cy="94" r="2.2" fill="#b45309"/>

            
            <rect x="75" y="98" width="90" height="52" rx="3" fill="none" stroke="#475569" stroke-width="1.5"/>
            <rect x="76" y="116" width="88" height="33" fill="#bae6fd" opacity="0.8"/>

            
            <line x1="60" y1="150" x2="180" y2="150" stroke="#1e2945" stroke-width="2.5"/>
            <line x1="70" y1="150" x2="56" y2="195" stroke="#475569" stroke-width="2.5"/>
            <line x1="170" y1="150" x2="184" y2="195" stroke="#475569" stroke-width="2.5"/>

            
            <path d="M120 195 Q 108 175 120 160 Q 132 175 120 195 Z" fill="#f59e0b"/>
            <path d="M120 195 Q 114 180 120 168 Q 126 180 120 195 Z" fill="#dc2626"/>
          </g>

          
          <g id="crystCool" class="cryst-group hidden">
            <text x="120" y="24" text-anchor="middle" font-size="12" font-weight="700" fill="#0284c7">Pure Crystals Form</text>
            <text x="120" y="42" text-anchor="middle" font-size="11" font-weight="600" fill="#475569">on slow cooling</text>

            
            <path d="M52 108 Q 120 172 188 108 Z" fill="#ffffff" stroke="#475569" stroke-width="2.5"/>
            
            <path d="M68 116 Q 120 164 172 116 Z" fill="#bae6fd" opacity="0.75"/>

            
            <polygon points="105,142 115,132 125,142 115,152" fill="#0284c7" stroke="#0369a1" stroke-width="1.5"/>
            <polygon points="85,137 95,129 103,138 93,146" fill="#0284c7" stroke="#0369a1" stroke-width="1.5"/>
            <polygon points="130,138 142,130 150,139 138,147" fill="#0284c7" stroke="#0369a1" stroke-width="1.5"/>
            <polygon points="112,128 122,118 130,127 120,137" fill="#0369a1" stroke="#0c4a6e" stroke-width="1.5"/>

            
            <circle cx="80" cy="122" r="2.2" fill="#b45309"/>
            <circle cx="160" cy="122" r="2.2" fill="#b45309"/>
            <circle cx="145" cy="118" r="2.2" fill="#b45309"/>

            
            <text x="120" y="186" text-anchor="middle" font-size="11" font-weight="700" fill="#1e2945">Pure Crystals + Mother Liquor</text>
          </g>
        </svg>
      </div>
      <div class="controls">
        <button class="btn active" id="btnHeat" type="button">1. Heat</button>
        <button class="btn" id="btnCool" type="button">2. Cool</button>
      </div>
    </div>
  </div>

  <script>
    const btnHeat = document.getElementById('btnHeat');
    const btnCool = document.getElementById('btnCool');
    const crystHeat = document.getElementById('crystHeat');
    const crystCool = document.getElementById('crystCool');

    function showHeat() {
      btnHeat.classList.add('active');
      btnCool.classList.remove('active');
      crystHeat.classList.remove('hidden');
      crystCool.classList.add('hidden');
    }

    function showCool() {
      btnCool.classList.add('active');
      btnHeat.classList.remove('active');
      crystHeat.classList.add('hidden');
      crystCool.classList.remove('hidden');
    }

    btnHeat.addEventListener('click', showHeat);
    btnCool.addEventListener('click', showCool);
  </script>
</body>
</html>

Analysing Physical Properties to Select Separation Methods

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<head>
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  <meta name="aspect-ratio" content="4:3">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      background: #ffffff;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: flex-start;
      padding: 8px 4px;
      width: 100%;
    }
    .header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 760px;
      padding: 0 10px 6px;
    }
    .title {
      font-size: 15px;
      font-weight: 700;
      color: #1e2945;
    }
    .btn-group {
      display: flex;
      gap: 6px;
    }
    .btn {
      font-size: 12px;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 6px;
      border: 1px solid #cbd5e1;
      background: #f8fafc;
      color: #1e2945;
      cursor: pointer;
      transition: all 0.2s ease;
    }
    .btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #2563eb;
    }
    .svg-container {
      width: 100%;
      max-width: 760px;
      aspect-ratio: 4/3;
      max-height: 480px;
    }
    svg {
      width: 100%;
      height: 100%;
      display: block;
    }
    .label {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      font-size: 12px;
      fill: #1e2945;
      font-weight: 600;
    }
    .sublabel {
      font-size: 10.5px;
      fill: #64748b;
      font-weight: 500;
    }
    .badge-text {
      font-size: 11px;
      fill: #1e2945;
      font-weight: 600;
    }
    .temp-hot { fill: #ef4444; font-weight: 700; font-size: 11px; }
    .temp-cool { fill: #0284c7; font-weight: 700; font-size: 11px; }
    .vapor-dot {
      transition: opacity 0.4s ease;
    }
    @keyframes riseSimple {
      0% { transform: translate(0, 0); opacity: 0; }
      20% { opacity: 0.8; }
      50% { transform: translate(0, -65px); opacity: 0.8; }
      100% { transform: translate(75px, -35px); opacity: 0; }
    }
    @keyframes riseFractional {
      0% { transform: translate(0, 0); opacity: 0; }
      20% { opacity: 0.8; }
      60% { transform: translate(0, -125px); opacity: 0.8; }
      100% { transform: translate(75px, -95px); opacity: 0; }
    }
    .flow-simple {
      animation: riseSimple 2.8s infinite ease-in-out;
    }
    .flow-fractional {
      animation: riseFractional 3.6s infinite ease-in-out;
    }
  </style>
</head>
<body>
  <div class="header">
    <div class="title">Distillation Methods</div>
    <div class="btn-group">
      <button class="btn active" id="btnBoth" onclick="setView('both')">Side-by-Side</button>
      <button class="btn" id="btnFocus" onclick="toggleVapor()">Animate Vapor</button>
    </div>
  </div>

  <div class="svg-container">
    <svg viewBox="0 0 760 480" xmlns="http://www.w3.org/2000/svg">
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          <stop offset="0%" stop-color="#bfdbfe" stop-opacity="0.8"/>
          <stop offset="100%" stop-color="#93c5fd" stop-opacity="0.8"/>
        </linearGradient>
        <linearGradient id="columnGrad" x1="0%" y1="100%" x2="0%" y2="0%">
          <stop offset="0%" stop-color="#fee2e2"/>
          <stop offset="50%" stop-color="#fef3c7"/>
          <stop offset="100%" stop-color="#e0f2fe"/>
        </linearGradient>
        <linearGradient id="heatGrad" x1="0%" y1="100%" x2="0%" y2="0%">
          <stop offset="0%" stop-color="#f97316"/>
          <stop offset="60%" stop-color="#eab308"/>
          <stop offset="100%" stop-color="#fef08a"/>
        </linearGradient>
        <linearGradient id="beadGrad" x1="0%" y1="0%" x2="100%" y2="100%">
          <stop offset="0%" stop-color="#ffffff"/>
          <stop offset="100%" stop-color="#cbd5e1"/>
        </linearGradient>

        <marker id="arrow" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
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        </marker>
        <marker id="arrow-blue" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="5" markerHeight="5" orient="auto-start-reverse">
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        </marker>
      </defs>

      
      <line x1="380" y1="20" x2="380" y2="460" stroke="#e2e8f0" stroke-width="1.5" stroke-dasharray="5 5" />

      
      <g id="simple-panel">
        
        <text x="190" y="34" text-anchor="middle" class="label" font-size="15" fill="#1e2945">Simple Distillation</text>
        <rect x="60" y="48" width="260" height="24" rx="12" fill="#eff6ff" stroke="#bfdbfe" stroke-width="1" />
        <text x="190" y="64" text-anchor="middle" class="badge-text" fill="#1d4ed8">Use: ΔT_b &gt; 25–50°C or Solid + Liquid</text>

        
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        <path d="M 134 395 Q 140 365 140 360 Q 140 365 146 395 Z" fill="url(#heatGrad)" opacity="0.9" />
        <path d="M 137 395 Q 140 375 140 370 Q 140 375 143 395 Z" fill="#ffffff" opacity="0.7" />

        
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        <circle cx="140" cy="330" r="32" fill="#f8fafc" stroke="#334155" stroke-width="2.5" />
        
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        <rect x="135" y="218" width="10" height="7" fill="#dc2626" rx="2" />

        
        <line x1="140" y1="216" x2="140" y2="258" stroke="#ef4444" stroke-width="2.5" stroke-linecap="round" />
        <circle cx="140" cy="260" r="2.5" fill="#ef4444" />
        <text x="96" y="222" class="sublabel" font-size="10">Thermometer</text>
        <line x1="126" y1="225" x2="137" y2="232" stroke="#94a3b8" stroke-width="1" marker-end="url(#arrow)" />

        
        <g transform="rotate(30, 177, 268)">
          
          <rect x="177" y="256" width="110" height="24" rx="4" fill="url(#coolWaterGrad)" stroke="#38bdf8" stroke-width="1.5" />
          
          <rect x="165" y="264" width="135" height="8" fill="#ffffff" stroke="#334155" stroke-width="2" />
          
          <rect x="265" y="280" width="8" height="10" fill="#bae6fd" stroke="#38bdf8" stroke-width="1" />
          <rect x="195" y="246" width="8" height="10" fill="#bae6fd" stroke="#38bdf8" stroke-width="1" />
        </g>

        
        <text x="276" y="360" class="sublabel" fill="#0284c7" font-weight="600">Water in</text>
        <path d="M 270 354 L 260 340" fill="none" stroke="#0284c7" stroke-width="1.2" marker-end="url(#arrow-blue)" />

        <text x="206" y="242" class="sublabel" fill="#0284c7" font-weight="600">Water out</text>
        <path d="M 218 248 L 222 260" fill="none" stroke="#0284c7" stroke-width="1.2" marker-end="url(#arrow-blue)" />

        
        <path d="M 285 330 L 295 352 L 295 385" fill="none" stroke="#334155" stroke-width="2" />
        
        <path d="M 278 385 L 278 435 Q 278 440 283 440 L 317 440 Q 322 440 322 435 L 322 385" fill="#f8fafc" stroke="#334155" stroke-width="2" />
        
        <path d="M 279 415 L 279 435 Q 279 439 284 439 L 316 439 Q 321 439 321 435 L 321 415 Z" fill="#38bdf8" opacity="0.6" />
        <line x1="279" y1="415" x2="321" y2="415" stroke="#0284c7" stroke-width="1" />

        
        <text x="300" y="460" text-anchor="middle" class="label">Pure Distillate</text>
        <text x="140" y="460" text-anchor="middle" class="sublabel">Heat Source</text>
        <text x="245" y="295" text-anchor="middle" class="label" fill="#0369a1">Condenser</text>

        
        <g id="vaporSimpleGroup" class="flow-simple">
          <circle cx="140" cy="310" r="3.5" fill="#3b82f6" opacity="0.8"/>
          <circle cx="140" cy="275" r="3.5" fill="#3b82f6" opacity="0.8"/>
          <circle cx="152" cy="245" r="3" fill="#3b82f6" opacity="0.8"/>
        </g>
      </g>


      
      <g id="fractional-panel">
        
        <text x="570" y="34" text-anchor="middle" class="label" font-size="15" fill="#1e2945">Fractional Distillation</text>
        <rect x="435" y="48" width="270" height="24" rx="12" fill="#fef2f2" stroke="#fecaca" stroke-width="1" />
        <text x="570" y="64" text-anchor="middle" class="badge-text" fill="#b91c1c">Use: Close Boiling Points (ΔT_b &lt; 25°C)</text>

        
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        <path d="M 514 395 Q 520 365 520 360 Q 520 365 526 395 Z" fill="url(#heatGrad)" opacity="0.9" />
        <path d="M 517 395 Q 520 375 520 370 Q 520 375 523 395 Z" fill="#ffffff" opacity="0.7" />

        
        <line x1="450" y1="440" x2="540" y2="440" stroke="#64748b" stroke-width="4" stroke-linecap="round"/>
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        <circle cx="520" cy="330" r="32" fill="#f8fafc" stroke="#334155" stroke-width="2.5" />
        
        <path d="M 491 340 A 32 32 0 0 0 549 340 Z" fill="#c084fc" opacity="0.6" />
        <line x1="490" y1="340" x2="550" y2="340" stroke="#9333ea" stroke-width="1" />

        
        <rect x="510" y="165" width="20" height="135" fill="url(#columnGrad)" stroke="#334155" stroke-width="2" rx="1"/>

        
        <g fill="url(#beadGrad)" stroke="#64748b" stroke-width="0.8">
          <circle cx="516" cy="290" r="3.5" /><circle cx="524" cy="290" r="3.5" />
          <circle cx="520" cy="282" r="3.5" /><circle cx="515" cy="274" r="3.5" /><circle cx="525" cy="274" r="3.5" />
          <circle cx="520" cy="266" r="3.5" /><circle cx="515" cy="258" r="3.5" /><circle cx="525" cy="258" r="3.5" />
          <circle cx="520" cy="250" r="3.5" /><circle cx="515" cy="242" r="3.5" /><circle cx="525" cy="242" r="3.5" />
          <circle cx="520" cy="234" r="3.5" /><circle cx="515" cy="226" r="3.5" /><circle cx="525" cy="226" r="3.5" />
          <circle cx="520" cy="218" r="3.5" /><circle cx="515" cy="210" r="3.5" /><circle cx="525" cy="210" r="3.5" />
          <circle cx="520" cy="202" r="3.5" /><circle cx="515" cy="194" r="3.5" /><circle cx="525" cy="194" r="3.5" />
          <circle cx="520" cy="186" r="3.5" /><circle cx="515" cy="178" r="3.5" /><circle cx="525" cy="178" r="3.5" />
          <circle cx="520" cy="170" r="3" />
        </g>

        
        <path d="M 498 174 L 498 290" fill="none" stroke="#94a3b8" stroke-width="1.5" marker-start="url(#arrow)" marker-end="url(#arrow)" />
        <text x="492" y="176" text-anchor="end" class="temp-cool">Cooler</text>
        <text x="492" y="294" text-anchor="end" class="temp-hot">Hotter</text>

        
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<!DOCTYPE html>
<html lang="en">
<head>
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    <button class="step-btn" data-step="3">4. Calculate R<sub>f</sub></button>
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</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">
  <title>Separation Pathway Flowchart</title>
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
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      color: #1e2945;
      padding: 12px;
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      justify-content: space-between;
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    }

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      border: 1.5px solid #e2e8f0;
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      font-size: 13px;
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    .tag-iron { background: #e2e8f0; color: #334155; }
    .tag-sand { background: #fef3c7; color: #92400e; }
    .tag-salt { background: #e0f2fe; color: #0369a1; }
    .tag-eth { background: #fce7f3; color: #9d174d; }
    .tag-wat { background: #dcfce7; color: #166534; }

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        gap: 8px;
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      cursor: pointer;
      display: flex;
      flex-direction: column;
      gap: 6px;
      position: relative;
    }

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      border-color: #22b7ff;
      box-shadow: 0 4px 14px rgba(34, 183, 255, 0.25);
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      justify-content: space-between;
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    .prop-mag { background: #fee2e2; color: #991b1b; }
    .prop-bp { background: #fdf2f8; color: #9d174d; }
    .prop-size { background: #fef3c7; color: #92400e; }
    .prop-sol { background: #e0f2fe; color: #075985; }

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      align-items: center;
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      font-weight: 700;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      user-select: none;
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      background: #22b7ff;
      transform: scale(1.25);
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</head>
<body>

  
  <div class="mixture-bar">
    <span>Mixture:</span>
    <span class="tag-iron">Iron</span>
    <span class="tag-sand">Sand</span>
    <span class="tag-salt">Salt</span>
    <span class="tag-eth">Ethanol</span>
    <span class="tag-wat">Water</span>
  </div>

  
  <div class="grid">
    
    <div class="step-card active" data-step="0">
      <div class="step-header">
        <span class="step-num">STEP 1</span>
        <span class="property-badge prop-mag">Magnetism</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">🧲</span>
        <span>Magnetic Separation</span>
      </div>
      <div class="result-row">
        <span class="condition-text">Dry mixture</span>
        <span class="isolated-target">✓ Iron Filings</span>
      </div>
    </div>

    
    <div class="step-card" data-step="1">
      <div class="step-header">
        <span class="step-num">STEP 2</span>
        <span class="property-badge prop-bp">Boiling Point</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">⚗️</span>
        <span>Fractional Distillation</span>
      </div>
      <div class="result-row">
        <span class="condition-text">78°C vapor</span>
        <span class="isolated-target">✓ Pure Ethanol</span>
      </div>
    </div>

    
    <div class="step-card" data-step="2">
      <div class="step-header">
        <span class="step-num">STEP 3</span>
        <span class="property-badge prop-size">Particle Size</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">🧪</span>
        <span>Filtration</span>
      </div>
      <div class="result-row">
        <span class="condition-text">Filter paper</span>
        <span class="isolated-target">✓ Sand Residue</span>
      </div>
    </div>

    
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      <div class="step-header">
        <span class="step-num">STEP 4</span>
        <span class="property-badge prop-sol">Solubility</span>
      </div>
      <div class="technique-row">
        <span class="tech-icon">🧂</span>
        <span>Crystallisation</span>
      </div>
      <div class="result-row">
        <span class="condition-text">Evaporate &amp; cool</span>
        <span class="isolated-target">✓ Pure Salt</span>
      </div>
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  <div class="header">
    <span class="title">Physical Separation Matrix</span>
    <span class="subtitle">Tap any property</span>
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    <div class="tile active" data-index="0" data-info="Separates insoluble solids from a liquid via particle size exclusion.">
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        <span class="prop-label">Property</span>
        <span class="prop-name">Particle<br>Size</span>
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        <span class="tech-tag">Insoluble Solid</span>
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    <div class="tile" data-index="1" data-info="Recovers dissolved solids by evaporating solvent until solute crystallises.">
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        <span class="prop-label">Property</span>
        <span class="prop-name">Solubility<br>in Solvent</span>
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          <path d="M35,16 Q55,34 75,16 Z" fill="#e2e8f0" stroke="#64748b" stroke-width="2" />
          
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        <span class="tech-name">Crystallisation</span>
        <span class="tech-tag">Dissolved Solute</span>
      </div>
    </div>

    
    <div class="tile" data-index="2" data-info="Separates miscible liquids based on differences in boiling points.">
      <div class="prop-col">
        <span class="prop-label">Property</span>
        <span class="prop-name">Boiling<br>Point (BP)</span>
      </div>
      <div class="arrow-col">→</div>
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        <span class="tech-name">Distillation</span>
        <span class="tech-tag">BP Difference</span>
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    <div class="tile" data-index="3" data-info="Separates dissolved substances via mobile vs stationary phase affinity.">
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        <span class="prop-label">Property</span>
        <span class="prop-name">Phase<br>Affinity</span>
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        <span class="tech-tag">Phase Partition</span>
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    <span id="infoText" class="info-desc">Separates insoluble solids from a liquid via particle size exclusion.</span>
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  <div class="header-bar">
    <span>Simple Distillation Apparatus</span>
    <span style="font-size: 11px; color: #0284c7; font-weight: 700;">Tap hot-spots to inspect</span>
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  <div class="info-card" id="infoCard">
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    <span class="info-text" id="infoText">Tap numbered markers to explore each component of the simple distillation apparatus.</span>
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      heat: {
        title: "Bunsen Burner",
        text: "Supplies thermal energy to boil the solution and maintain vapor flow."
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      condenser: {
        title: "Liebig Condenser",
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</body>
</html>

Simple Distillation: Principles and Apparatus

<!DOCTYPE html>
<html lang="en">
<head>
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      <span aria-hidden="true">✓</span> Correct Flow (Bottom In)
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        btnIncorrect.className = 'toggle-btn';
        btnIncorrect.setAttribute('aria-selected', 'false');

        jacketFull.style.display = 'block';
        jacketPartial.style.display = 'none';

        flowCorrect.style.display = 'block';
        flowIncorrect.style.display = 'none';

        correctCondensate.style.display = 'block';
        incorrectCondensate.style.display = 'none';
        lblVaporEscape.style.display = 'none';

        lblTopPort.textContent = 'Warm Water Out';
        lblTopPort.setAttribute('fill', '#c2410c');

        lblBottomPort.textContent = 'Cold Water In';
        lblBottomPort.setAttribute('fill', '#0369a1');
      } else {
        btnCorrect.className = 'toggle-btn';
        btnCorrect.setAttribute('aria-selected', 'false');
        btnIncorrect.className = 'toggle-btn active incorrect';
        btnIncorrect.setAttribute('aria-selected', 'true');

        jacketFull.style.display = 'none';
        jacketPartial.style.display = 'block';

        flowCorrect.style.display = 'none';
        flowIncorrect.style.display = 'block';

        correctCondensate.style.display = 'none';
        incorrectCondensate.style.display = 'block';
        lblVaporEscape.style.display = 'block';

        lblTopPort.textContent = 'Water In (Top)';
        lblTopPort.setAttribute('fill', '#0369a1');

        lblBottomPort.textContent = 'Water Out (Drains)';
        lblBottomPort.setAttribute('fill', '#475569');
      }
    }

    btnCorrect.addEventListener('click', () => setMode(true));
    btnIncorrect.addEventListener('click', () => setMode(false));
  </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;
      color: #1e2945;
      background: #ffffff;
      padding: 10px;
      user-select: none;
      -webkit-user-select: none;
    }
    
    .nav-bar {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 6px;
      margin-bottom: 8px;
    }
    .step-tabs {
      display: flex;
      gap: 4px;
      flex: 1;
    }
    .step-btn {
      flex: 1;
      padding: 6px 4px;
      font-size: 13px;
      font-weight: 600;
      background: #f1f5f9;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      color: #475569;
      cursor: pointer;
      text-align: center;
      transition: background 0.2s, color 0.2s, border-color 0.2s;
      white-space: nowrap;
    }
    .step-btn.active {
      background: #2563eb;
      color: #ffffff;
      border-color: #1d4ed8;
    }
    .play-btn {
      padding: 6px 12px;
      font-size: 13px;
      font-weight: 600;
      background: #f8fafc;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      color: #1e2945;
      cursor: pointer;
    }

    .canvas-container {
      position: relative;
      width: 100%;
      height: 380px;
      background: #f8fafc;
      border: 1px solid #e2e8f0;
      border-radius: 8px;
      overflow: hidden;
    }

    svg {
      width: 100%;
      height: 100%;
      display: block;
    }

    /* SVG Animations */
    .steam-bubble {
      animation: riseUp 1.8s infinite linear;
    }
    @keyframes riseUp {
      0% { transform: translateY(0); opacity: 0; }
      50% { opacity: 0.8; }
      100% { transform: translateY(-35px); opacity: 0; }
    }

    .drop {
      animation: drip 1.2s infinite ease-in;
    }
    @keyframes drip {
      0% { transform: translateY(0); opacity: 0; }
      30% { opacity: 1; }
      90% { transform: translateY(32px); opacity: 1; }
      100% { transform: translateY(34px); opacity: 0; }
    }

    .flame-flicker {
      animation: flicker 0.4s infinite alternate ease-in-out;
      transform-origin: 105px 335px;
    }
    @keyframes flicker {
      0% { transform: scaleY(0.92) scaleX(0.96); }
      100% { transform: scaleY(1.08) scaleX(1.04); }
    }

    /* Badges */
    .status-badge {
      position: absolute;
      top: 10px;
      right: 10px;
      background: rgba(255, 255, 255, 0.95);
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 6px 10px;
      font-size: 13px;
      font-weight: 600;
      color: #0f172a;
      box-shadow: 0 1px 4px rgba(0,0,0,0.06);
    }
    .badge-hl {
      color: #2563eb;
    }
  </style>
</head>
<body>

  <div class="nav-bar">
    <div class="step-tabs">
      <button class="step-btn active" id="btn-0" onclick="setStep(0)">1. Mixture</button>
      <button class="step-btn" id="btn-1" onclick="setStep(1)">2. Boiling &amp; Cooling</button>
      <button class="step-btn" id="btn-2" onclick="setStep(2)">3. Separated</button>
    </div>
    <button class="play-btn" id="playBtn" onclick="togglePlay()">⏸</button>
  </div>

  <div class="canvas-container">
    <div class="status-badge" id="statusBadge">
      Flask: <span class="badge-hl">Dilute CuSO₄(aq)</span>
    </div>

    <svg viewBox="0 0 540 380">
      <defs>
        
        <linearGradient id="flaskSolution1" x1="0" y1="0" x2="0" y2="1">
          <stop offset="0%" stop-color="#60a5fa" stop-opacity="0.8"/>
          <stop offset="100%" stop-color="#3b82f6" stop-opacity="0.95"/>
        </linearGradient>
        <linearGradient id="flaskSolution2" x1="0" y1="0" x2="0" y2="1">
          <stop offset="0%" stop-color="#2563eb" stop-opacity="0.9"/>
          <stop offset="100%" stop-color="#1e40af" stop-opacity="1"/>
        </linearGradient>
        <linearGradient id="waterGrad" x1="0" y1="0" x2="0" y2="1">
          <stop offset="0%" stop-color="#bae6fd" stop-opacity="0.6"/>
          <stop offset="100%" stop-color="#7dd3fc" stop-opacity="0.85"/>
        </linearGradient>
        <linearGradient id="jacketGrad" x1="0" y1="0" x2="1" y2="1">
          <stop offset="0%" stop-color="#0284c7" stop-opacity="0.18"/>
          <stop offset="100%" stop-color="#38bdf8" stop-opacity="0.28"/>
        </linearGradient>
        <linearGradient id="flameGrad" x1="0" y1="1" x2="0" y2="0">
          <stop offset="0%" stop-color="#f97316"/>
          <stop offset="60%" stop-color="#fbbf24"/>
          <stop offset="100%" stop-color="#60a5fa"/>
        </linearGradient>
      </defs>

      
      
      <line x1="60" y1="340" x2="90" y2="245" stroke="#64748b" stroke-width="3.5" stroke-linecap="round"/>
      <line x1="150" y1="340" x2="120" y2="245" stroke="#64748b" stroke-width="3.5" stroke-linecap="round"/>
      <line x1="105" y1="340" x2="105" y2="245" stroke="#94a3b8" stroke-width="2.5" stroke-linecap="round"/>
      <line x1="75" y1="245" x2="135" y2="245" stroke="#334155" stroke-width="4" stroke-linecap="round"/>
      
      <line x1="80" y1="243" x2="130" y2="243" stroke="#94a3b8" stroke-width="2" stroke-dasharray="2,2"/>

      
      <rect x="98" y="295" width="14" height="45" fill="#64748b" rx="2"/>
      <rect x="85" y="340" width="40" height="7" fill="#334155" rx="2"/>
      
      <g id="flameGroup" class="flame-flicker">
        <path d="M 100 295 Q 105 255 105 255 Q 105 255 110 295 Z" fill="url(#flameGrad)"/>
      </g>

      
      <rect x="420" y="340" width="80" height="7" fill="#cbd5e1" rx="2"/>

      
      
      
      
      <g id="flaskContents">
        
        <g id="sol-step-0">
          <path d="M 67 215 C 67 236 84 240 105 240 C 126 240 143 236 143 215 C 137 205 73 205 67 215 Z" fill="url(#flaskSolution1)"/>
          <ellipse cx="105" cy="207" rx="36" ry="7" fill="#93c5fd" opacity="0.6"/>
          
          <circle cx="95" cy="235" r="2.5" fill="#475569"/>
          <circle cx="108" cy="237" r="3" fill="#475569"/>
          <circle cx="118" cy="234" r="2.5" fill="#475569"/>
        </g>
        
        
        <g id="sol-step-1" style="display:none;">
          <path d="M 75 227 C 78 238 90 240 105 240 C 120 240 132 238 135 227 C 130 222 80 222 75 227 Z" fill="url(#flaskSolution2)"/>
          <ellipse cx="105" cy="223" rx="28" ry="5" fill="#3b82f6" opacity="0.8"/>
          
          <circle cx="95" cy="235" r="2.5" fill="#475569"/>
          <circle cx="108" cy="237" r="3" fill="#475569"/>
          <circle cx="118" cy="234" r="2.5" fill="#475569"/>
          
          <g class="steam-bubble">
            <circle cx="98" cy="210" r="3" fill="#ffffff" opacity="0.7"/>
            <circle cx="112" cy="205" r="4" fill="#ffffff" opacity="0.7"/>
            <circle cx="104" cy="190" r="3.5" fill="#ffffff" opacity="0.7"/>
          </g>
        </g>

        
        <g id="sol-step-2" style="display:none;">
          <path d="M 85 237 Q 105 235 125 237 Q 105 242 85 237 Z" fill="#1e40af"/>
          <circle cx="92" cy="237" r="2.5" fill="#93c5fd"/>
          <circle cx="102" cy="236" r="3" fill="#1d4ed8"/>
          <circle cx="112" cy="237" r="2.5" fill="#60a5fa"/>
          <circle cx="118" cy="236" r="3" fill="#93c5fd"/>
          <circle cx="95" cy="235" r="2.5" fill="#475569"/>
          <circle cx="108" cy="237" r="3" fill="#475569"/>
          <text x="105" y="218" text-anchor="middle" font-size="11" font-weight="700" fill="#1e3a8a">CuSO₄ solid</text>
        </g>
      </g>

      
      <path d="M 98 120 L 98 165 C 73 175 60 205 65 225 C 72 250 138 250 145 225 C 150 205 137 175 112 165 L 112 120" 
            fill="none" stroke="#64748b" stroke-width="2.5" stroke-linejoin="round"/>

      
      <rect x="96" y="112" width="18" height="10" fill="#94a3b8" rx="2"/>

      
      <rect x="103" y="60" width="4" height="95" fill="#e2e8f0" stroke="#94a3b8" stroke-width="1"/>
      <line id="thermoLiquid" x1="105" y1="150" x2="105" y2="90" stroke="#ef4444" stroke-width="2.5"/>
      <circle cx="105" cy="152" r="3.5" fill="#ef4444"/>
      
      
      <g id="tempBadge">
        <rect x="32" y="68" width="62" height="22" fill="#ffffff" stroke="#ef4444" stroke-width="1.5" rx="4"/>
        <text id="tempText" x="63" y="83" font-size="12" font-weight="700" fill="#dc2626" text-anchor="middle">100°C</text>
        <line x1="94" y1="79" x2="103" y2="79" stroke="#ef4444" stroke-width="1.5"/>
      </g>

      
      
      <g id="condenserGroup">
        
        <line x1="112" y1="140" x2="390" y2="280" stroke="#64748b" stroke-width="4"/>
        <line x1="112" y1="140" x2="390" y2="280" stroke="#ffffff" stroke-width="2"/>

        
        <line x1="160" y1="164" x2="345" y2="257" stroke="url(#jacketGrad)" stroke-width="24" stroke-linecap="round"/>
        <line x1="160" y1="164" x2="345" y2="257" stroke="#38bdf8" stroke-width="24" stroke-linecap="round" opacity="0.3"/>
        <line x1="160" y1="164" x2="345" y2="257" stroke="#0284c7" stroke-width="1.5" stroke-linecap="round" fill="none"/>

        
        <line x1="330" y1="262" x2="330" y2="285" stroke="#0284c7" stroke-width="5" stroke-linecap="round"/>
        <path d="M 330 300 L 330 285" stroke="#0284c7" stroke-width="2" marker-end="url(#arrow)"/>
        <text x="330" y="315" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Water in (cold)</text>
        <path d="M 330 298 L 330 287" stroke="#0284c7" stroke-width="2"/>
        <polygon points="327,288 333,288 330,282" fill="#0284c7"/>

        
        <line x1="175" y1="160" x2="175" y2="135" stroke="#0284c7" stroke-width="5" stroke-linecap="round"/>
        <text x="175" y="118" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Water out (warm)</text>
        <line x1="175" y1="133" x2="175" y2="123" stroke="#0284c7" stroke-width="2"/>
        <polygon points="172,125 178,125 175,119" fill="#0284c7"/>

        
        <g id="condenserDrops" style="display:none;">
          <circle cx="210" cy="190" r="2.5" fill="#38bdf8"/>
          <circle cx="250" cy="210" r="3" fill="#0284c7"/>
          <circle cx="290" cy="230" r="3.5" fill="#0284c7"/>
          <circle cx="330" cy="250" r="3.5" fill="#0284c7"/>
        </g>
      </g>

      
      
      <path d="M 388 279 L 410 290 L 410 305" fill="none" stroke="#64748b" stroke-width="3" stroke-linecap="round"/>
      
      
      <g id="drippingWater" style="display:none;">
        <g class="drop">
          <circle cx="410" cy="308" r="2.5" fill="#38bdf8"/>
        </g>
      </g>

      
      
      <g id="receiverContents">
        
        
        <g id="rec-step-1" style="display:none;">
          <polygon points="432,335 488,335 480,315 440,315" fill="url(#waterGrad)"/>
          <ellipse cx="460" cy="315" rx="20" ry="3.5" fill="#e0f2fe"/>
        </g>
        
        <g id="rec-step-2" style="display:none;">
          <polygon points="432,335 488,335 474,290 446,290" fill="url(#waterGrad)"/>
          <ellipse cx="460" cy="290" rx="14" ry="3" fill="#e0f2fe"/>
          <text x="460" y="322" font-size="11" font-weight="700" fill="#0369a1" text-anchor="middle">Pure H₂O</text>
        </g>
      </g>

      
      <path d="M 452 270 L 452 280 L 430 338 C 428 340 430 340 435 340 L 485 340 C 490 340 492 340 490 338 L 468 280 L 468 270 Z" 
            fill="none" stroke="#64748b" stroke-width="2" stroke-linejoin="round"/>

      
      <text x="105" y="42" font-size="12" font-weight="700" fill="#334155" text-anchor="middle">Thermometer</text>
      <text x="260" y="152" font-size="12" font-weight="700" fill="#0369a1" text-anchor="middle">Liebig Condenser</text>
      <text x="460" y="258" font-size="12" font-weight="700" fill="#334155" text-anchor="middle">Distillate</text>
    </svg>
  </div>

  <script>
    let currentStep = 0;
    let timer = null;
    let isPlaying = true;

    const badges = [
      'Flask: <span class="badge-hl">Dilute CuSO₄(aq)</span> (Starting mixture)',
      'Vapor: <span class="badge-hl">100°C Steam</span> cools to Pure Liquid',
      'Result: <span class="badge-hl">Pure Water</span> separated from <span class="badge-hl">Solid CuSO₄</span>'
    ];

    function updateView() {
      // Buttons
      for (let i = 0; i < 3; i++) {
        document.getElementById(`btn-${i}`).classList.toggle('active', i === currentStep);
      }

      // Badge text
      document.getElementById('statusBadge').innerHTML = badges[currentStep];

      // Distilling flask states
      document.getElementById('sol-step-0').style.display = (currentStep === 0) ? 'inline' : 'none';
      document.getElementById('sol-step-1').style.display = (currentStep === 1) ? 'inline' : 'none';
      document.getElementById('sol-step-2').style.display = (currentStep === 2) ? 'inline' : 'none';

      // Flame
      document.getElementById('flameGroup').style.display = (currentStep === 2) ? 'none' : 'inline';

      // Condenser droplets & drip
      document.getElementById('condenserDrops').style.display = (currentStep === 1) ? 'inline' : 'none';
      document.getElementById('drippingWater').style.display = (currentStep === 1) ? 'inline' : 'none';

      // Thermometer reading
      const thermoLiquid = document.getElementById('thermoLiquid');
      const tempText = document.getElementById('tempText');
      if (currentStep === 0) {
        thermoLiquid.setAttribute('y2', '125');
        tempText.textContent = '20°C';
      } else if (currentStep === 1) {
        thermoLiquid.setAttribute('y2', '90');
        tempText.textContent = '100°C';
      } else {
        thermoLiquid.setAttribute('y2', '140');
        tempText.textContent = '25°C';
      }

      // Receiving flask states
      document.getElementById('rec-step-1').style.display = (currentStep === 1) ? 'inline' : 'none';
      document.getElementById('rec-step-2').style.display = (currentStep === 2) ? 'inline' : 'none';
    }

    function setStep(idx) {
      currentStep = idx;
      updateView();
    }

    function nextStep() {
      currentStep = (currentStep + 1) % 3;
      updateView();
    }

    function togglePlay() {
      isPlaying = !isPlaying;
      document.getElementById('playBtn').textContent = isPlaying ? '⏸' : '▶';
      if (isPlaying) {
        startTimer();
      } else {
        clearInterval(timer);
      }
    }

    function startTimer() {
      clearInterval(timer);
      timer = setInterval(nextStep, 3600);
    }

    // Initialize
    updateView();
    startTimer();
  </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;
      color: #1e2945;
      background: #ffffff;
      padding: 12px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      user-select: none;
    }

    .header-bar {
      width: 100%;
      max-width: 600px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 8px;
    }

    .legend {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 13px;
      font-weight: 600;
    }

    .legend-item {
      display: flex;
      align-items: center;
      gap: 5px;
    }

    .dot-na {
      width: 14px;
      height: 14px;
      border-radius: 50%;
      background: #10b981;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 10px;
      font-weight: bold;
    }

    .dot-cl {
      width: 16px;
      height: 16px;
      border-radius: 50%;
      background: #f97316;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-size: 10px;
      font-weight: bold;
    }

    .dot-h2o {
      width: 14px;
      height: 14px;
      border-radius: 50%;
      background: #3b82f6;
      display: inline-block;
      position: relative;
    }

    .canvas-container {
      position: relative;
      width: 100%;
      max-width: 600px;
      height: 270px;
      background: #f8fafc;
      border-radius: 12px;
      border: 1px solid #e2e8f0;
      overflow: hidden;
    }

    canvas {
      width: 100%;
      height: 100%;
      display: block;
    }

    .status-badge {
      position: absolute;
      top: 10px;
      right: 10px;
      background: rgba(255, 255, 255, 0.92);
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      padding: 4px 8px;
      font-size: 12px;
      font-weight: 600;
      color: #334155;
      pointer-events: none;
    }

    .controls {
      width: 100%;
      max-width: 600px;
      display: flex;
      flex-direction: column;
      gap: 8px;
      margin-top: 10px;
    }

    .slider-row {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .temp-label {
      font-size: 14px;
      font-weight: 700;
      min-width: 65px;
      color: #0f172a;
    }

    input[type="range"] {
      flex: 1;
      -webkit-appearance: none;
      height: 6px;
      border-radius: 3px;
      background: linear-gradient(to right, #38bdf8, #f59e0b, #ef4444);
      outline: none;
      cursor: pointer;
    }

    input[type="range"]::-webkit-slider-thumb {
      -webkit-appearance: none;
      width: 20px;
      height: 20px;
      border-radius: 50%;
      background: #ffffff;
      border: 2px solid #0284c7;
      box-shadow: 0 1px 4px rgba(0,0,0,0.2);
      cursor: pointer;
    }

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

    .btn {
      flex: 1;
      padding: 7px 12px;
      font-size: 13px;
      font-weight: 600;
      border: 1px solid #cbd5e1;
      border-radius: 6px;
      background: #ffffff;
      color: #334155;
      cursor: pointer;
      text-align: center;
      transition: background 0.2s, border-color 0.2s, color 0.2s;
    }

    .btn.active {
      background: #0284c7;
      color: #ffffff;
      border-color: #0284c7;
    }
  </style>
</head>
<body>

  <div class="header-bar">
    <div class="legend">
      <div class="legend-item"><span class="dot-na">+</span> Na⁺</div>
      <div class="legend-item"><span class="dot-cl">−</span> Cl⁻</div>
      <div class="legend-item"><span class="dot-h2o"></span> H₂O</div>
    </div>
  </div>

  <div class="canvas-container">
    <canvas id="simCanvas"></canvas>
    <div id="statusBadge" class="status-badge">Liquid Solution</div>
  </div>

  <div class="controls">
    <div class="slider-row">
      <span id="tempDisplay" class="temp-label">20°C</span>
      <input type="range" id="tempSlider" min="20" max="100" value="20" step="1">
    </div>
    <div class="btn-group">
      <button class="btn active" id="btn20">20°C (Room Temp)</button>
      <button class="btn" id="btn100">100°C (Boiling)</button>
    </div>
  </div>

  <script>
    const canvas = document.getElementById('simCanvas');
    const ctx = canvas.getContext('2d');
    const tempSlider = document.getElementById('tempSlider');
    const tempDisplay = document.getElementById('tempDisplay');
    const statusBadge = document.getElementById('statusBadge');
    const btn20 = document.getElementById('btn20');
    const btn100 = document.getElementById('btn100');

    let width, height;
    let currentTemp = 20;

    function resize() {
      const rect = canvas.getBoundingClientRect();
      width = rect.width;
      height = rect.height;
      canvas.width = width * window.devicePixelRatio;
      canvas.height = height * window.devicePixelRatio;
      ctx.scale(window.devicePixelRatio, window.devicePixelRatio);
    }
    window.addEventListener('resize', resize);
    resize();

    // Lattice target positions for salt ions at dry state
    const cols = 5;
    const rows = 3;
    const latticeSpacing = 22;

    const ions = [];
    let idCounter = 0;
    for (let r = 0; r < rows; r++) {
      for (let c = 0; c < cols; c++) {
        const type = (r + c) % 2 === 0 ? 'Na' : 'Cl';
        ions.push({
          id: idCounter++,
          type: type,
          r: type === 'Na' ? 7 : 9,
          x: Math.random() * (width || 300) * 0.8 + 20,
          y: Math.random() * (height || 200) * 0.4 + 120,
          vx: (Math.random() - 0.5) * 1.5,
          vy: (Math.random() - 0.5) * 1.5,
          targetCol: c,
          targetRow: r
        });
      }
    }

    const waters = [];
    const waterCount = 36;
    for (let i = 0; i < waterCount; i++) {
      waters.push({
        x: Math.random() * (width || 300) * 0.85 + 15,
        y: Math.random() * 120 + 80,
        vx: (Math.random() - 0.5) * 2,
        vy: (Math.random() - 0.5) * 2,
        angle: Math.random() * Math.PI * 2,
        vRot: (Math.random() - 0.5) * 0.05,
        isGas: false,
        fade: 1.0
      });
    }

    function setTemp(t) {
      currentTemp = Math.round(t);
      tempSlider.value = currentTemp;
      tempDisplay.textContent = currentTemp + '°C';
      
      if (currentTemp >= 95) {
        statusBadge.textContent = 'Steam Escapes • Salt Remains';
        btn100.classList.add('active');
        btn20.classList.remove('active');
      } else if (currentTemp <= 30) {
        statusBadge.textContent = 'Liquid Solution';
        btn20.classList.add('active');
        btn100.classList.remove('active');
      } else {
        statusBadge.textContent = 'Heating...';
        btn20.classList.remove('active');
        btn100.classList.remove('active');
      }
    }

    tempSlider.addEventListener('input', (e) => setTemp(e.target.value));
    btn20.addEventListener('click', () => setTemp(20));
    btn100.addEventListener('click', () => setTemp(100));

    function drawWater(x, y, angle, alpha = 1.0) {
      ctx.save();
      ctx.globalAlpha = alpha;
      ctx.translate(x, y);
      ctx.rotate(angle);

      // Hydrogens (white/light blue)
      ctx.fillStyle = '#93c5fd';
      ctx.beginPath();
      ctx.arc(-5, -4, 3.5, 0, Math.PI * 2);
      ctx.arc(5, -4, 3.5, 0, Math.PI * 2);
      ctx.fill();

      // Oxygen (blue)
      ctx.fillStyle = '#2563eb';
      ctx.beginPath();
      ctx.arc(0, 2, 5.5, 0, Math.PI * 2);
      ctx.fill();

      ctx.restore();
    }

    function drawIon(ion) {
      ctx.save();
      ctx.beginPath();
      ctx.arc(ion.x, ion.y, ion.r, 0, Math.PI * 2);
      if (ion.type === 'Na') {
        ctx.fillStyle = '#10b981';
        ctx.fill();
        ctx.fillStyle = '#ffffff';
        ctx.font = 'bold 9px sans-serif';
        ctx.textAlign = 'center';
        ctx.textBaseline = 'middle';
        ctx.fillText('+', ion.x, ion.y + 0.5);
      } else {
        ctx.fillStyle = '#f97316';
        ctx.fill();
        ctx.fillStyle = '#ffffff';
        ctx.font = 'bold 11px sans-serif';
        ctx.textAlign = 'center';
        ctx.textBaseline = 'middle';
        ctx.fillText('−', ion.x, ion.y);
      }
      ctx.restore();
    }

    function animate() {
      ctx.clearRect(0, 0, width, height);

      const boilFactor = Math.max(0, (currentTemp - 20) / 80); // 0 at 20°C, 1 at 100°C
      const speedMult = 0.5 + boilFactor * 2.2;

      // Draw container walls / bottom
      ctx.strokeStyle = '#94a3b8';
      ctx.lineWidth = 3;
      ctx.beginPath();
      ctx.moveTo(16, 20);
      ctx.lineTo(16, height - 16);
      ctx.lineTo(width - 16, height - 16);
      ctx.lineTo(width - 16, 20);
      ctx.stroke();

      // Draw liquid level line (drops as water boils off)
      const liquidLevel = (height - 30) - (1 - boilFactor) * (height * 0.55);
      if (boilFactor < 0.98) {
        ctx.fillStyle = 'rgba(239, 246, 255, 0.45)';
        ctx.fillRect(18, liquidLevel, width - 36, (height - 16) - liquidLevel);

        ctx.strokeStyle = 'rgba(96, 165, 250, 0.4)';
        ctx.lineWidth = 1.5;
        ctx.setLineDash([4, 4]);
        ctx.beginPath();
        ctx.moveTo(18, liquidLevel);
        ctx.lineTo(width - 18, liquidLevel);
        ctx.stroke();
        ctx.setLineDash([]);
      }

      // Heat source glow at bottom when hot
      if (boilFactor > 0.1) {
        const glow = ctx.createLinearGradient(0, height - 16, 0, height);
        glow.addColorStop(0, `rgba(239, 68, 68, ${boilFactor * 0.4})`);
        glow.addColorStop(1, 'rgba(239, 68, 68, 0)');
        ctx.fillStyle = glow;
        ctx.fillRect(16, height - 16, width - 32, 16);
      }

      // Update & render Ions
      const latticeCenterX = width / 2;
      const latticeBaseY = height - 28;

      ions.forEach(ion => {
        if (boilFactor > 0.6) {
          // Attract towards solid lattice
          const targetX = latticeCenterX + (ion.targetCol - (cols - 1) / 2) * latticeSpacing;
          const targetY = latticeBaseY - (rows - 1 - ion.targetRow) * latticeSpacing;
          const blend = (boilFactor - 0.6) / 0.4;

          ion.x += (targetX - ion.x) * (0.05 + blend * 0.1);
          ion.y += (targetY - ion.y) * (0.05 + blend * 0.1);

          // Small vibration
          ion.x += (Math.random() - 0.5) * (1 + blend * 1.5);
          ion.y += (Math.random() - 0.5) * (1 + blend * 1.5);
        } else {
          // Free aqueous ions
          ion.x += ion.vx * speedMult;
          ion.y += ion.vy * speedMult;

          // Contain inside liquid area
          if (ion.x < 30) { ion.x = 30; ion.vx *= -1; }
          if (ion.x > width - 30) { ion.x = width - 30; ion.vx *= -1; }
          if (ion.y < liquidLevel + 10) { ion.y = liquidLevel + 10; ion.vy *= -1; }
          if (ion.y > height - 30) { ion.y = height - 30; ion.vy *= -1; }
        }
        drawIon(ion);
      });

      // Update & render Water molecules
      waters.forEach(w => {
        w.angle += w.vRot * speedMult;

        if (boilFactor > 0.4) {
          // Rising steam behavior
          w.vy -= 0.08 * boilFactor;
          w.y += w.vy * speedMult;
          w.x += w.vx * (1 + boilFactor);

          // Escaping through the top
          if (w.y < -15) {
            w.y = height - 35;
            w.x = Math.random() * (width - 60) + 30;
            w.vy = (Math.random() - 0.5) * 1.5;
            w.vx = (Math.random() - 0.5) * 1.5;
          }
        } else {
          // Liquid state wander
          w.x += w.vx * speedMult;
          w.y += w.vy * speedMult;

          if (w.x < 25) { w.x = 25; w.vx *= -1; }
          if (w.x > width - 25) { w.x = width - 25; w.vx *= -1; }
          if (w.y < liquidLevel) { w.y = liquidLevel; w.vy *= -1; }
          if (w.y > height - 25) { w.y = height - 25; w.vy *= -1; }
        }

        // Fading slightly if high up steam
        let alpha = 1.0;
        if (w.y < 35) alpha = Math.max(0.2, w.y / 35);

        drawWater(w.x, w.y, w.angle, alpha);
      });

      requestAnimationFrame(animate);
    }

    animate();
  </script>
</body>
</html>

UK-GCSE-SCIENCE-CHEM-CA-01-06

Aligned learning resources

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