Resonance Structures & Delocalisation
See the resonance forms of ozone, nitrate, carbonate, nitrite and benzene and the averaged hybrid.
Pick a molecule, flip between its resonance structures, then switch on the hybrid to see the real, averaged molecule.
About the Resonance Structures & Delocalisation
Free resonance structures & delocalisation. See the resonance forms of ozone, nitrate, carbonate, nitrite and benzene and the averaged hybrid. Drag, change the sliders and see the result live. No sign-up, works on phone and computer. Built for molecules, the resonance structures & delocalisation runs instantly in your browser: change a setting or drag an object and the result updates at once, so you learn by trying things out rather than only reading about them.
See the resonance forms of ozone, nitrate, carbonate, nitrite and benzene and the averaged hybrid. Use it to explore molecules ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Resonance Structures & Delocalisation
- Use the controls to change Molecule, Structure. The simulation reacts instantly.
- Pick an option such as Ozone O₃, Nitrate NO₃⁻, Carbonate CO₃²⁻, Nitrite NO₂⁻ to switch modes or load an example.
- Press "Show the hybrid", "Auto flip" to start, reset or change what is happening.
- Where you see a glowing handle, object, weight or atom, drag it with your mouse or finger. Everything responds in real time.
- Watch the readouts and graphs update as you experiment, and compare what you see with the key ideas below.
Things to try
- Flip through the three forms of nitrate.
- Show the hybrid of benzene and read the bond order.
- Compare ozone's two O–O bonds in each form and in the hybrid.
Key ideas you can learn
- Some molecules need more than one Lewis structure.
- The real molecule is a hybrid, an average of them.
- Bond orders in the hybrid are fractions like 1.5.
- Delocalisation makes molecules more stable.
Where this is used in the real world
Resonance explains why all C–C bonds in benzene are equal, why carboxylic acids are acidic and how dyes get their colours.
Who is this simulation for?
Chemistry and biology students learning bonding and molecular shape, and teachers who need an interactive 3D model instead of a textbook drawing.
For teachers: project it on the board, let students predict what will happen, then run it together. For students: change one thing at a time and write down what changes.
Frequently asked questions
What is a resonance hybrid?
The real structure of the molecule, which is an average of all valid resonance forms.
Does the molecule flip between the structures?
No. The molecule always has the single hybrid structure; the separate drawings are only a bookkeeping tool.
Is the Resonance Structures & Delocalisation free to use?
Yes. It is completely free, with no signup, no download and no ads inside the simulation. It runs in your web browser.
Does the Resonance Structures & Delocalisation work on a phone or tablet?
Yes. It uses touch as well as the mouse, so you can drag objects with your finger. A larger screen makes the controls easier to see.