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Resonance Structure Generator

Explore resonance structures of common molecules and ions. View step-by-step explanations and understand electron delocalization.

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Remember

Resonance structures are different ways to draw the same molecule. The actual molecule is a hybrid — electrons don't actually "jump" between structures!

🔬 Select Molecule

📊 Resonance Structures

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Select a molecule from the list to view its resonance structures

📜 Rules for Drawing Resonance Structures

1

Only electrons move, not atoms

Atoms must stay in the same positions. Only π electrons and lone pairs can be moved between adjacent atoms.

2

Follow the octet rule

Second-row elements (C, N, O, F) cannot exceed 8 electrons. Third-row elements (S, P) can exceed the octet.

3

Do not break single bonds

Single bonds (σ bonds) cannot be broken in resonance structures. Only π bonds and lone pairs participate.

4

Total charge must be conserved

The sum of formal charges must be the same in all resonance structures and equal to the overall molecular charge.

📖 Understanding Resonance

Resonance is a key concept in chemistry that explains why some molecules are more stable than expected. When electrons can be delocalized across multiple atoms, the molecule gains extra stability called resonance stabilization.

Key Concepts

  • Electron Delocalization: π electrons spread over multiple atoms
  • Resonance Hybrid: The true structure is a blend of all forms
  • Curved Arrows: Show electron movement between structures
  • Equivalent Structures: Contribute equally to the hybrid
  • Major/Minor Contributors: More stable structures contribute more

Common Functional Groups with Resonance

Carboxylates

RCOO⁻

Amides

RCONH₂

Esters

RCOOR

Nitro Groups

RNO₂

Aromatics

C₆H₆

Enolates

RCH=CO⁻

⚡ Quick Facts

🔬 Benzene has 36 kcal/mol resonance energy

⚖️ Equal structures = equal contribution

📉 More structures = more stable molecule

🎯 Negative charge prefers electronegative atoms

💡 Study Tips

• Practice drawing arrows showing electron movement
• Count electrons before and after — they must match!
• Check formal charges on each atom
• Remember: atoms stay fixed, only electrons move

Frequently Asked Questions

Resonance structures are different Lewis structures that can be drawn for a molecule when electrons can be delocalized. The actual molecule is a hybrid of all resonance structures, not switching between them. Resonance occurs when π electrons or lone pairs can be distributed in multiple valid ways.

Look for: (1) Adjacent atoms with π bonds and lone pairs, (2) Conjugated systems (alternating single and double bonds), (3) Charged species adjacent to π bonds, (4) Aromatic rings. If electrons can move to an adjacent atom without breaking a single bond, resonance is possible.

More stable (major) contributors have: (1) More covalent bonds, (2) Complete octets on all atoms, (3) Negative charges on more electronegative atoms, (4) Minimal formal charges, (5) Negative and positive charges close together if both exist.

The resonance hybrid is the actual structure of the molecule - a weighted average of all resonance structures. It represents the true electron distribution. Bond lengths and charges in the hybrid are intermediate between those shown in individual resonance structures.

No! This is a common misconception. The molecule does not flip between resonance structures. The resonance structures are just different ways we draw the same molecule. The actual molecule exists as one hybrid structure with delocalized electrons.

Resonance affects molecular stability (resonance-stabilized molecules are more stable), reactivity (determines where reactions occur), acidity/basicity (conjugate bases with resonance are more stable), and physical properties like bond lengths and dipole moments.

⚗️ Disclaimer: This tool is for educational purposes. For advanced molecular modeling, please use specialized chemistry software. Always verify structures with your textbook or instructor.