Everything around you — the air, the sea, your own body — is made of a few dozen kinds of atom stuck together in different patterns. Drag some atoms onto the workbench, push them together and see which patterns actually hold.
Molecule & Reaction Lab
Drag an element onto the workbench:
Empty workbench — drag some atoms in here
🗑️
Drag atoms onto the bench, push two together, then hit BOND.
Score
0
Atoms
0/14
Discovered
0/11
⬜H2 · ???
⬜O2 · ???
⬜N2 · ???
⬜H2O · ???
⬜CO2 · ???
⬜CH4 · ???
⬜NH3 · ???
⬜H2O2 · ???
⬜C2H6 · ???
⬜HCl · ???
⬜NaCl · ???
Tip: the little amber number on an atom is how many bonding arms it still has free. Push two atoms together and press ⚡ BOND; press it again on the same pair for a double or triple bond. Drag an atom sharply away to snap a bond, or drop it in the bin to get rid of it.
The science behind it 📚
Four short ideas. Tap any one to read more.
🔍What is an atom, really?The smallest piece of an element — a nucleus with a cloud of electrons around it.Learn more ▾Close ▴
An atom is the smallest piece of an element you can have and still call it that element. In the middle sits a tiny nucleus packed with protons and neutrons, and around it buzzes a cloud of electrons.
The number of protons decides which element it is: 1 proton is hydrogen, 6 is carbon, 8 is oxygen.
Atoms are unbelievably small — about a million of them side by side would span the width of a human hair.
The electrons on the outside are the part that does chemistry. The nucleus mostly stays out of it.
🤝Why atoms hold handsAtoms share electrons to fill their outer shell. Those shared pairs are the arms on the workbench.Learn more ▾Close ▴
Atoms are happiest when their outer electron shell is full. Most atoms are a few electrons short, so they team up with neighbours to share. Those shared pairs are the bonds — the arms on the workbench.
Hydrogen and chlorine each have 1 arm, oxygen has 2, nitrogen has 3, and carbon has 4.
Sharing one pair of electrons is a single bond, two pairs is a double bond, three is a triple bond.
A molecule works out when every arm has found a partner — no arms left dangling.
⚡Sharing vs. giving awaySome atoms share electrons, others hand them over completely — and that changes everything.Learn more ▾Close ▴
Not every bond is a friendly share. Sodium would rather hand its outer electron over completely, and chlorine is delighted to take it. Now sodium is positive, chlorine is negative, and opposite charges pull together.
Sharing electrons is a covalent bond — water, methane and ammonia are all built this way.
Giving an electron away makes an ionic bond — table salt is the classic example.
Ionic compounds stack into crystals, which is why salt comes as little cubes you can see.
📐Reading a chemical formulaH₂O is a recipe: the letters are elements, the little numbers count the atoms.Learn more ▾Close ▴
A formula is a recipe written in shorthand. The letters are the elements and the small number after each one counts how many of that atom are in the molecule.
H₂O means 2 hydrogen atoms and 1 oxygen atom. No number means just one.
CO₂ and CH₄ use the same carbon atom, but the partners change everything: one you breathe out, the other burns.
In a reaction, atoms are never created or destroyed — they only get rearranged. 2H₂ + O₂ → 2H₂O uses up exactly the atoms it started with.