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Lewis structure builder

Count the valence electrons, place them, and see what the molecule becomes.

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Explanation mode
HHO

A Lewis structure shows which atoms are bonded and where the electrons are. It is not the shape — the terminal atoms are spaced evenly because that is how the structure is written.

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Description of this simulation

H2O has 8 valence electrons to place. O is the central atom, joined to 2 atoms. Every bond is a single bond. 2 lone pairs sit on O. That gives 8 electrons around the central atom, a complete octet.

H2O

Valence electrons
8
Central atom
O
Atoms bonded to it
2
Lone pairs on the centre
2
Electrons around the centre
8a complete octet
Formal charge on the centre
0

What shape does this make?

These same numbers are AX2E2 in the geometry lab, which makes the molecule bent.

Open the geometry lab

What this model shows — and what it simplifies

Educational Model

A Lewis structure records which atoms are bonded and where the electrons sit.

Where do we see this in real life?

Formal charges are how a chemist picks between two structures that both satisfy the octet rule. The one that spreads charge least is the one that describes the real molecule, and that choice decides which bond a reaction attacks.