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Override for the tutor's lesson content generation calls. Auto uses the system default (Claude Sonnet 5 for lesson text, Opus 5 for diagrams).

Lesson generation model

System default

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Tutoring abilities

Why does table salt shatter into brittle cubes, candle wax melt in your hands, and a copper wire bend without breaking?

Every chemical bond in the universe comes down to one fundamental rule: **electrostatic attraction**, the invisible pull between positive and negative charges.

<!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="1:1">
  <style>
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
      user-select: none;
      -webkit-user-select: none;
    }

    body {
      background-color: #f8f9fa;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      color: #1e2945;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      min-height: 100%;
      padding: 16px 12px;
      overflow-x: hidden;
    }

    .nav-tabs {
      display: flex;
      gap: 6px;
      width: 100%;
      max-width: 420px;
      background: #e2e8f0;
      padding: 4px;
      border-radius: 12px;
    }

    .tab-btn {
      flex: 1;
      border: none;
      background: transparent;
      padding: 8px 4px;
      font-size: 14px;
      font-weight: 700;
      color: #64748b;
      border-radius: 8px;
      cursor: pointer;
      transition: background 0.2s ease, color 0.2s ease, box-shadow 0.2s ease;
      text-align: center;
    }

    .tab-btn.active {
      background: #ffffff;
      color: #1e2945;
      box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
    }

    .stage-container {
      position: relative;
      width: 100%;
      max-width: 420px;
      height: 220px;
      background: #ffffff;
      border-radius: 16px;
      box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
      border: 1px solid #e2e8f0;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
      margin: 12px 0;
    }

    .field-lines {
      position: absolute;
      inset: 0;
      width: 100%;
      height: 100%;
      pointer-events: none;
    }

    .charge-track {
      position: relative;
      width: 100%;
      height: 100%;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .charge {
      position: absolute;
      width: 64px;
      height: 64px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 32px;
      font-weight: 800;
      color: #ffffff;
      z-index: 10;
      transition: transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
    }

    .charge-pos {
      background: radial-gradient(circle at 35% 35%, #ff5252, #dc2626);
      box-shadow: 0 0 20px rgba(239, 68, 68, 0.45), 0 4px 10px rgba(220, 38, 38, 0.3);
    }

    .charge-neg {
      background: radial-gradient(circle at 35% 35%, #38bdf8, #0284c7);
      box-shadow: 0 0 20px rgba(56, 189, 248, 0.45), 0 4px 10px rgba(2, 132, 199, 0.3);
    }

    .force-group {
      position: absolute;
      display: flex;
      align-items: center;
      justify-content: center;
      pointer-events: none;
      z-index: 5;
      transition: all 0.4s ease;
    }

    .force-arrow {
      height: 4px;
      background: #10b981;
      position: relative;
      transition: width 0.3s ease, background 0.3s ease;
      border-radius: 2px;
    }

    .force-arrow.repel {
      background: #f59e0b;
    }

    .arrow-head {
      position: absolute;
      top: 50%;
      width: 0;
      height: 0;
      border-top: 6px solid transparent;
      border-bottom: 6px solid transparent;
      transform: translateY(-50%);
    }

    .arrow-head-left {
      left: -2px;
      border-right: 10px solid #10b981;
    }

    .arrow-head-right {
      right: -2px;
      border-left: 10px solid #10b981;
    }

    .force-arrow.repel .arrow-head-left {
      border-right-color: #f59e0b;
    }

    .force-arrow.repel .arrow-head-right {
      border-left-color: #f59e0b;
    }

    .status-badge {
      position: absolute;
      top: 14px;
      background: #f1f5f9;
      color: #1e2945;
      font-size: 14px;
      font-weight: 700;
      padding: 4px 14px;
      border-radius: 20px;
      border: 1px solid #cbd5e1;
      display: flex;
      align-items: center;
      gap: 6px;
      z-index: 20;
    }

    .dot-indicator {
      width: 8px;
      height: 8px;
      border-radius: 50%;
      background: #10b981;
    }

    .dot-indicator.repel {
      background: #f59e0b;
    }

    .controls-card {
      width: 100%;
      max-width: 420px;
      background: #ffffff;
      border-radius: 14px;
      border: 1px solid #e2e8f0;
      padding: 12px 16px;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

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

    .slider-label {
      font-size: 14px;
      font-weight: 700;
      color: #1e2945;
      min-width: 60px;
    }

    input[type=range] {
      flex: 1;
      accent-color: #2563eb;
      height: 6px;
      background: #e2e8f0;
      border-radius: 4px;
      outline: none;
      cursor: pointer;
    }

    .legend-row {
      display: flex;
      justify-content: space-around;
      font-size: 13px;
      color: #64748b;
      font-weight: 600;
      padding-top: 4px;
      border-top: 1px solid #f1f5f9;
    }

    .legend-item {
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .circle-mini {
      width: 10px;
      height: 10px;
      border-radius: 50%;
    }
  </style>
</head>
<body>

  <div class="nav-tabs">
    <button class="tab-btn active" onclick="setMode('opposite')">+ &minus; Opposite</button>
    <button class="tab-btn" onclick="setMode('pos-pos')">+ + Like</button>
    <button class="tab-btn" onclick="setMode('neg-neg')">&minus; &minus; Like</button>
  </div>

  <div class="stage-container">
    <svg class="field-lines" id="svgCanvas"></svg>

    <div class="status-badge" id="statusBadge">
      <span class="dot-indicator" id="statusDot"></span>
      <span id="statusText">Attraction (Pull)</span>
    </div>

    <div class="charge-track">
      <div class="charge charge-pos" id="chargeLeft">+</div>
      <div class="force-group" id="forceGroup">
        <div class="force-arrow" id="forceArrowLeft">
          <div class="arrow-head" id="headLeft"></div>
        </div>
        <div style="width: 24px;"></div>
        <div class="force-arrow" id="forceArrowRight">
          <div class="arrow-head" id="headRight"></div>
        </div>
      </div>
      <div class="charge charge-neg" id="chargeRight">&minus;</div>
    </div>
  </div>

  <div class="controls-card">
    <div class="slider-row">
      <span class="slider-label">Distance</span>
      <input type="range" id="distSlider" min="90" max="150" value="115" oninput="updatePositions()">
    </div>
    <div class="legend-row">
      <div class="legend-item">
        <span class="circle-mini" style="background:#ef4444;"></span>
        <span>Positive (+)</span>
      </div>
      <div class="legend-item">
        <span class="circle-mini" style="background:#0284c7;"></span>
        <span>Negative (&minus;)</span>
      </div>
    </div>
  </div>

  <script>
    let currentMode = 'opposite';
    const slider = document.getElementById('distSlider');
    const chargeLeft = document.getElementById('chargeLeft');
    const chargeRight = document.getElementById('chargeRight');
    const statusText = document.getElementById('statusText');
    const statusDot = document.getElementById('statusDot');
    const arrowLeft = document.getElementById('forceArrowLeft');
    const arrowRight = document.getElementById('forceArrowRight');
    const headLeft = document.getElementById('headLeft');
    const headRight = document.getElementById('headRight');
    const svgCanvas = document.getElementById('svgCanvas');
    const tabs = document.querySelectorAll('.tab-btn');

    function setMode(mode) {
      currentMode = mode;
      tabs.forEach((tab, i) => {
        tab.classList.toggle('active', 
          (i === 0 && mode === 'opposite') ||
          (i === 1 && mode === 'pos-pos') ||
          (i === 2 && mode === 'neg-neg')
        );
      });
      render();
    }

    function render() {
      const isOpposite = currentMode === 'opposite';
      const isPosPos = currentMode === 'pos-pos';

      // Update Charge Appearances
      if (isOpposite) {
        chargeLeft.className = 'charge charge-pos';
        chargeLeft.innerHTML = '+';
        chargeRight.className = 'charge charge-neg';
        chargeRight.innerHTML = '&minus;';
      } else if (isPosPos) {
        chargeLeft.className = 'charge charge-pos';
        chargeLeft.innerHTML = '+';
        chargeRight.className = 'charge charge-pos';
        chargeRight.innerHTML = '+';
      } else {
        chargeLeft.className = 'charge charge-neg';
        chargeLeft.innerHTML = '&minus;';
        chargeRight.className = 'charge charge-neg';
        chargeRight.innerHTML = '&minus;';
      }

      // Update Status Badge
      statusText.textContent = isOpposite ? 'Attraction (Pull)' : 'Repulsion (Push)';
      statusDot.className = 'dot-indicator' + (isOpposite ? '' : ' repel');

      // Update Force Vector Arrows
      arrowLeft.className = 'force-arrow' + (isOpposite ? '' : ' repel');
      arrowRight.className = 'force-arrow' + (isOpposite ? '' : ' repel');

      if (isOpposite) {
        headLeft.className = 'arrow-head arrow-head-right';
        headRight.className = 'arrow-head arrow-head-left';
      } else {
        headLeft.className = 'arrow-head arrow-head-left';
        headRight.className = 'arrow-head arrow-head-right';
      }

      updatePositions();
    }

    function updatePositions() {
      const d = parseFloat(slider.value);
      const isOpposite = currentMode === 'opposite';
      
      // Calculate force strength (inverse square representation)
      const forceScale = Math.pow(150 / d, 2);
      const arrowLength = Math.min(48, Math.max(14, 18 * forceScale));

      // Dynamic positions
      chargeLeft.style.transform = `translateX(-${d}px)`;
      chargeRight.style.transform = `translateX(${d}px)`;

      arrowLeft.style.width = `${arrowLength}px`;
      arrowRight.style.width = `${arrowLength}px`;

      drawFieldLines(d, isOpposite);
    }

    function drawFieldLines(d, isOpposite) {
      const w = svgCanvas.clientWidth || 380;
      const h = svgCanvas.clientHeight || 220;
      const cx = w / 2;
      const cy = h / 2;
      const x1 = cx - d;
      const x2 = cx + d;

      let html = '';
      if (isOpposite) {
        // Curved attractive field lines connecting charges
        const offsets = [-45, -25, 0, 25, 45];
        offsets.forEach(offset => {
          if (offset === 0) {
            html += `<line x1="${x1 + 32}" y1="${cy}" x2="${x2 - 32}" y2="${cy}" stroke="#10b981" stroke-width="1.5" stroke-dasharray="4,4" opacity="0.6"/>`;
          } else {
            const ctrlY = cy + offset * 1.8;
            html += `<path d="M ${x1 + 20} ${cy + offset*0.4} Q ${cx} ${ctrlY} ${x2 - 20} ${cy + offset*0.4}" fill="none" stroke="#10b981" stroke-width="1.5" stroke-dasharray="4,4" opacity="0.45"/>`;
          }
        });
      } else {
        // Repulsive field lines bending away at the center plane
        const offsets = [-45, -25, 25, 45];
        offsets.forEach(offset => {
          const bendLeftX = cx - (d * 0.35);
          const bendRightX = cx + (d * 0.35);
          html += `<path d="M ${x1 + 24} ${cy + offset*0.3} Q ${bendLeftX} ${cy + offset*0.5} ${bendLeftX} ${cy + offset*1.8}" fill="none" stroke="#f59e0b" stroke-width="1.5" stroke-dasharray="4,4" opacity="0.45"/>`;
          html += `<path d="M ${x2 - 24} ${cy + offset*0.3} Q ${bendRightX} ${cy + offset*0.5} ${bendRightX} ${cy + offset*1.8}" fill="none" stroke="#f59e0b" stroke-width="1.5" stroke-dasharray="4,4" opacity="0.45"/>`;
        });
      }
      svgCanvas.innerHTML = html;
    }

    window.addEventListener('resize', () => updatePositions());
    render();
  </script>
</body>
</html>

In 1785, Charles-Augustin de Coulomb proved that opposite electric charges pull toward each other with a force that strengthens as charges get larger or move closer together.

How does this single force create three completely different types of chemical bonds?

An **ionic bond** occurs between a metal and a non-metal when valence electrons are transferred to achieve full outer shells.

The metal atom loses electrons to form a positively charged **cation**, while the non-metal atom gains those electrons to form a negatively charged **anion**.

<!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;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      height: 100%;
      min-height: 420px;
      padding: 12px 16px;
      user-select: none;
    }

    /* Stepper UI */
    .controls {
      display: flex;
      align-items: center;
      gap: 8px;
      margin-bottom: 8px;
      z-index: 10;
    }
    .step-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;
    }
    .step-btn.active {
      background: #0284c7;
      border-color: #0284c7;
      color: #ffffff;
      box-shadow: 0 2px 6px rgba(2, 132, 199, 0.3);
    }
    .play-btn {
      background: #ffffff;
      border: 1px solid #cbd5e1;
      border-radius: 50%;
      width: 32px;
      height: 32px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      cursor: pointer;
      color: #1e2945;
      margin-left: 4px;
    }

    /* Diagram Stage */
    .stage {
      position: relative;
      width: 100%;
      max-width: 580px;
      flex: 1;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .view {
      position: absolute;
      inset: 0;
      width: 100%;
      height: 100%;
      opacity: 0;
      pointer-events: none;
      transition: opacity 0.4s ease, transform 0.4s ease;
      transform: scale(0.96);
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .view.active {
      opacity: 1;
      pointer-events: auto;
      transform: scale(1);
    }

    svg {
      width: 100%;
      height: 100%;
      overflow: visible;
    }

    /* Transfer Electron Animation */
    @keyframes transferMotion {
      0%, 15% { transform: translate(0, 0); opacity: 1; }
      60%, 85% { transform: translate(168px, -24px); opacity: 1; }
      90%, 100% { transform: translate(168px, -24px); opacity: 0; }
    }
    .moving-electron {
      animation: transferMotion 3.2s infinite ease-in-out;
    }

    /* Pulse for lattice attractions */
    @keyframes pulseForce {
      0%, 100% { stroke-opacity: 0.35; stroke-dashoffset: 0; }
      50% { stroke-opacity: 0.9; stroke-dashoffset: 6; }
    }
    .force-line {
      stroke: #f59e0b;
      stroke-width: 2.5;
      stroke-dasharray: 4 3;
      animation: pulseForce 2s infinite ease-in-out;
    }
  </style>
</head>
<body>

  
  <div class="controls">
    <button class="step-btn active" onclick="setStep(0)">1. Transfer</button>
    <button class="step-btn" onclick="setStep(1)">2. Ions</button>
    <button class="step-btn" onclick="setStep(2)">3. Giant Lattice</button>
    <button class="play-btn" id="playBtn" onclick="togglePlay()" title="Play/Pause">⏸</button>
  </div>

  
  <div class="stage">
    
    
    <div class="view active" id="view-0">
      <svg viewBox="0 0 520 300">
        
        <path d="M 205 130 Q 260 70 315 125" fill="none" stroke="#0284c7" stroke-width="2.5" stroke-dasharray="5 4" marker-end="url(#arrowhead)" />
        <defs>
          <marker id="arrowhead" markerWidth="8" markerHeight="6" refX="6" refY="3" orient="auto">
            <polygon points="0 0, 8 3, 0 6" fill="#0284c7" />
          </marker>
        </defs>

        
        <g transform="translate(130, 150)">
          <circle cx="0" cy="0" r="18" fill="#e0f2fe" stroke="#0284c7" stroke-width="2" />
          <text x="0" y="5" text-anchor="middle" font-size="14" font-weight="bold" fill="#0369a1">Na</text>
          
          
          <circle cx="0" cy="0" r="38" fill="none" stroke="#cbd5e1" stroke-width="1.5" />
          <circle cx="0" cy="0" r="58" fill="none" stroke="#cbd5e1" stroke-width="1.5" />
          <circle cx="0" cy="0" r="78" fill="none" stroke="#94a3b8" stroke-width="1.5" stroke-dasharray="3 3" />

          
          <circle cx="0" cy="-38" r="4" fill="#0284c7" />
          <circle cx="0" cy="38" r="4" fill="#0284c7" />
          
          
          <circle cx="-58" cy="0" r="4" fill="#0284c7" />
          <circle cx="58" cy="0" r="4" fill="#0284c7" />
          <circle cx="-41" cy="-41" r="4" fill="#0284c7" />
          <circle cx="41" cy="-41" r="4" fill="#0284c7" />
          <circle cx="-41" cy="41" r="4" fill="#0284c7" />
          <circle cx="41" cy="41" r="4" fill="#0284c7" />
          <circle cx="0" cy="-58" r="4" fill="#0284c7" />
          <circle cx="0" cy="58" r="4" fill="#0284c7" />

          
          <g class="moving-electron">
            <circle cx="78" cy="0" r="5" fill="#f59e0b" stroke="#b45309" stroke-width="1" />
          </g>

          <text x="0" y="105" text-anchor="middle" font-size="13" font-weight="600" fill="#475569">Na (2,8,1)</text>
        </g>

        
        <g transform="translate(390, 150)">
          <circle cx="0" cy="0" r="18" fill="#dcfce7" stroke="#16a34a" stroke-width="2" />
          <text x="0" y="5" text-anchor="middle" font-size="14" font-weight="bold" fill="#15803d">Cl</text>

          
          <circle cx="0" cy="0" r="38" fill="none" stroke="#cbd5e1" stroke-width="1.5" />
          <circle cx="0" cy="0" r="58" fill="none" stroke="#cbd5e1" stroke-width="1.5" />
          <circle cx="0" cy="0" r="78" fill="none" stroke="#cbd5e1" stroke-width="1.5" />

          
          <circle cx="0" cy="-38" r="4" fill="#16a34a" />
          <circle cx="0" cy="38" r="4" fill="#16a34a" />

          
          <circle cx="-58" cy="0" r="4" fill="#16a34a" />
          <circle cx="58" cy="0" r="4" fill="#16a34a" />
          <circle cx="-41" cy="-41" r="4" fill="#16a34a" />
          <circle cx="41" cy="-41" r="4" fill="#16a34a" />
          <circle cx="-41" cy="41" r="4" fill="#16a34a" />
          <circle cx="41" cy="41" r="4" fill="#16a34a" />
          <circle cx="0" cy="-58" r="4" fill="#16a34a" />
          <circle cx="0" cy="58" r="4" fill="#16a34a" />

          
          <circle cx="0" cy="-78" r="4" fill="#16a34a" />
          <circle cx="0" cy="78" r="4" fill="#16a34a" />
          <circle cx="78" cy="0" r="4" fill="#16a34a" />
          <circle cx="-55" cy="-55" r="4" fill="#16a34a" />
          <circle cx="55" cy="-55" r="4" fill="#16a34a" />
          <circle cx="-55" cy="55" r="4" fill="#16a34a" />
          <circle cx="55" cy="55" r="4" fill="#16a34a" />

          
          <circle cx="-78" cy="0" r="5" fill="none" stroke="#f59e0b" stroke-width="1.5" stroke-dasharray="2 2" />

          <text x="0" y="105" text-anchor="middle" font-size="13" font-weight="600" fill="#475569">Cl (2,8,7)</text>
        </g>
      </svg>
    </div>

    
    <div class="view" id="view-1">
      <svg viewBox="0 0 520 300">
        
        <g transform="translate(260, 145)">
          <path d="M -30 0 L 30 0" stroke="#f59e0b" stroke-width="3" stroke-dasharray="4 3" />
          <text x="0" y="-12" text-anchor="middle" font-size="12" font-weight="bold" fill="#d97706">Attraction</text>
        </g>

        
        <g transform="translate(130, 145)">
          
          <path d="M -75 -75 L -85 -75 L -85 75 L -75 75" fill="none" stroke="#1e2945" stroke-width="2.5" />
          <path d="M 75 -75 L 85 -75 L 85 75 L 75 75" fill="none" stroke="#1e2945" stroke-width="2.5" />
          <text x="96" y="-62" font-size="24" font-weight="bold" fill="#0284c7">+</text>

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For example, in sodium chloride, $\text{Na}$ transfers its single valence electron to $\text{Cl}$, creating $\text{Na}^+$ and $\text{Cl}^-$. Strong electrostatic attractions then lock millions of these ions into a giant **ionic lattice**.

A common mistake is thinking an ionic bond is a single stick connecting one sodium to one chlorine. In reality, each $\text{Na}^+$ is simultaneously attracted to all surrounding $\text{Cl}^-$ ions in every direction.

What happens when two non-metal atoms meet, and neither is willing to give up its electrons?

## Covalent Bonding: Shared Electron Pairs

A **covalent bond** forms between non-metal atoms when they share pairs of electrons to achieve stable electron configurations.

In 1916, chemist Gilbert N. Lewis suggested that atoms share electron pairs; the bond is the electrostatic attraction between the positively charged nuclei and the shared negative electrons sitting between them.

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      <strong>Covalent Bond:</strong> The simultaneous electrostatic pull from <strong>both positive nuclei (+)</strong> holding the <strong>shared electron pair (e⁻)</strong> together.
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In a molecule of chlorine gas ($\text{Cl}_2$), each atom contributes one electron to form a single **shared pair**.

Notice that covalent bonds are still strictly electrostatic: the two positive nuclei are both pulling on the exact same localized pool of negative charge.

What happens in a pure solid metal, where every single atom wants to shed electrons?

## Metallic Bonding: A Sea of Delocalized Electrons

A **metallic bond** is the electrostatic attraction between a regular lattice of positive metal ions and a surrounding sea of **delocalized electrons**.

Metal atoms release their valence electrons, allowing them to drift freely throughout the entire structure rather than staying bound to one atom.

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      <div class="ion-sample">+</div>
      <span>Metal Ion (Cu²⁺)</span>
    </div>
    <div class="legend-item">
      <div class="electron-sample"></div>
      <span>Delocalised e⁻ Sea</span>
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      <span>Electrostatic Attraction</span>
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Because these free electrons move through the whole crystal, they act as an electrostatic cement holding the positive ions together even when the metal is hammered or bent.

To master bonding on your exam, always identify which positive species and which negative species are pulling on each other.

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  <div class="header-title">The Three Electrostatic Models</div>

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science

Electrostatic Forces in Chemical Bonding. Explain ionic, covalent, and metallic bonding in terms of electrostatic forces and the transfer or sharing of electrons.

GCSE Chemistry: Bonding, Structure and the Properties of Matter

Structure and Bonding: Ionic, Covalent, and Metallic Models

Developing Understanding of Chemical Bonding: Key Stage 4 / GCSE Resources

To ensure student mastery of GCSE standard UK-GCSE-SCIENCE-CHEM-SBM-02-02, explicitly teach bonding through the unifying lens of electrostatic attractions rather than treating each bond as an isolated mnemonic. Use a comparison matrix highlighting (1) particle types involved, (2) electron behaviour (transferred, shared, delocalised), and (3) specific positive-to-negative electrostatic attraction vectors for each bond type. Address the common trap where students equate covalent bonding solely to 'sharing' without identifying the attractive force between positive nuclei and the shared negative electron cloud.

Electrostatic Forces in Chemical Bonding

Ionic Bonding: Electron Transfer

Covalent Bonding: Shared Electron Pairs