How to build a molecule
Every molecule is just atoms joined by chemical bonds. In this builder you do exactly that: tap atoms from the palette into your tray, watch the formula update live, then press Bond them! The tool checks your atoms and, if they make a real molecule, snaps them into the correct Lewis structure and shows its shape and polarity.
- Challenge mode names a target — “Build water, H₂O” — and you assemble it. Each one you finish adds to your score.
- Sandbox mode lets you free-build. Find a real molecule and it joins your collection. Can you discover all 14?
Why building beats memorizing
Snapping atoms together turns abstract formulas into something you do. You quickly feel why H₂O needs two hydrogens and one oxygen, why CO₂ is built from one carbon and two oxygens, and how the same handful of atoms recombine into very different molecules. That hands-on intuition is exactly what makes Lewis structures and molecular shapes click later.
From atoms to bonds to shape
When you bond atoms, the builder shows the finished molecule’s geometry and whether it’s polar — the payoff of the whole bonding story:
- Which atoms bond, and how many, comes from each atom’s valence electrons.
- Whether a bond is ionic or covalent depends on electronegativity.
- The finished molecule’s shape follows VSEPR, and its polarity depends on whether the bond dipoles cancel.
Build a familiar one to start — try hydrogen and oxygen for water, or carbon and oxygen for carbon dioxide.
Use it in class
Project it and have students race to build a target, or challenge them to discover every molecule in sandbox mode. It’s free to embed on your own site or LMS — one line of code, no signup.