Lewis Structure

NH3 Lewis Structure

Ammonia

NH3 has nitrogen in the center with three N-H single bonds and one lone pair on nitrogen.

Use the diagram and steps below to check the ammonia Lewis structure, NH3 Lewis dot structure, valence electrons, formal charges, and molecular shape.

NH3

Ammonia

8 e-
N H H H
Valence electrons8
Central atomN
GeometryTrigonal pyramidal
Bond angleAbout 107 deg
PolarityPolar
Electron geometryTetrahedral

VSEPR Geometry

Molecular geometry Trigonal pyramidal
Electron geometry Tetrahedral
Bond angle About 107 deg
Polarity Polar
Valence electrons 8
Bonding / lone pairs 3 / 1
Central atom N
Electron regions 4

How to Draw NH3: Step-by-Step

1

Parse the molecular formula

NH3 -> N, H, H, H

The molecule contains one nitrogen atom and three hydrogen atoms.

2

Count total valence electrons

5 + 1 + 1 + 1 = 8

Nitrogen contributes 5 electrons. Three hydrogens contribute 3.

3

Choose the central atom

Central atom: N

Hydrogen cannot be central, so nitrogen is placed in the center.

4

Draw the skeleton

Three N-H single bonds

The three bonds use 6 electrons.

5

Place the remaining electrons

One lone pair on N

The final 2 electrons become a lone pair on nitrogen.

6

Final answer

The NH3 Lewis structure has three N-H single bonds and one lone pair on nitrogen.

Formal Charges

AtomFormal charge
N0
H0 each

Common Mistakes

  • The lone pair changes the molecular shape from trigonal planar to trigonal pyramidal.
  • Hydrogen atoms should not receive lone pairs.

FAQ

What is the Lewis structure for NH3?

The NH3 Lewis structure has three N-H single bonds and one lone pair on nitrogen.

What is the Lewis dot structure for NH3?

The Lewis dot structure for NH3 is the electron-dot drawing shown above. The NH3 Lewis structure has three N-H single bonds and one lone pair on nitrogen.

How many valence electrons does NH3 have?

NH3 has 8 total valence electrons in this Lewis structure.

What is the molecular geometry of NH3?

NH3 has trigonal pyramidal molecular geometry and tetrahedral electron geometry.

Is NH3 polar or nonpolar?

NH3 is polar in the Lewis structure shown here. Its molecular geometry is Trigonal pyramidal.

References

Method notes are aligned with standard Lewis structure steps: count valence electrons, draw a skeleton, distribute electrons, form multiple bonds when needed, and check formal charges and resonance.

OpenStax Chemistry 2e: Lewis Symbols and Structures and Formal Charges and Resonance.