Central-Atom Molecular Geometry & Property Builder

①

Guided walkthrough

Observe a completed example, then rebuild it with step-by-step support.

Choose Molecule

NH₃

8 valence electrons
neutral molecule

The complete molecule is shown. Select Start Build to construct it from the central atom.

1 · Add Atoms

Selected: N

Bonding centre N

Every new atom bonds to N.

2 · Connect Atoms

3 · Place Electrons

Electron Budget

Electrons placed0 / 0

Used: 0Remaining: 0

Choose a molecule to begin.

Current Structure

NH₃ · Ammonia

✓Structure valid

Drag to rotate the molecule

Lewis StructureSelect an atom

↔ Drag the model to inspect its three-dimensional arrangement

◇Structure Analysis

VSEPR notation

AX₃E

Electron domains

Electron geometry

Tetrahedral

Molecular shape

Trigonal pyramidal

Bond angle

≈ 107°

Hybridisation*

sp³

➜Molecular Polarity

Polar molecule

The N–H bond dipoles do not cancel because the molecule is not symmetrical.

≈Intermolecular Forces

London dispersion forces act between all molecules.

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Why is NH₃ trigonal pyramidal rather than trigonal planar?

Use the live structure and property panels as evidence.