Study Guides/Chemistry/NH3 Hybridization & Structure
Study Guide · Chemistry

Hybridization and Structure of Ammonia (NH3)

In Chemical Bonding (Class 11 Chemistry), determining the hybridization and geometric shape of molecules is a very important topic. Let's analyze the Ammonia (NH₃) molecule.

Question (Click to Flip)

What is the hybridization of NH3?

Answer

The hybridization of the central nitrogen atom in NH3 (Ammonia) is sp3.

Card 1 of 2 free previews

Key Facts

Central Atom: Nitrogen (N).

Hybridization: sp³.

Electron Geometry: Tetrahedral.

Molecular Shape: Trigonal Pyramidal (due to 1 lone pair).

Bond Angle: ~ 107°.

1. Hybridization of NH3

To find the hybridization, we look at the central Nitrogen (N) atom.

  • Nitrogen has 5 valence electrons.
  • It forms 3 single covalent bonds with 3 Hydrogen atoms. (This uses 3 electrons).
  • It has 2 electrons left over, which form 1 Lone Pair.
  • Total Steric Number = (Number of bonded atoms) + (Number of lone pairs) = 3 + 1 = 4.
  • A steric number of 4 corresponds to sp³ Hybridization. Therefore, the Nitrogen atom in NH₃ is sp³ hybridized.

2. Structure and Shape of NH3

Normally, an sp³ hybridized molecule (like Methane, CH₄) has a perfect Tetrahedral geometry with bond angles of 109.5°.

However, NH₃ has a Lone Pair of electrons sitting on top of the Nitrogen atom. According to the VSEPR theory, the lone pair repels the bonded pairs of electrons strongly, pushing the hydrogen atoms closer together.

Because of this repulsion:

  • The shape distorts from a perfect tetrahedron into a Trigonal Pyramidal shape.
  • The bond angle squeezes down from 109.5° to approximately 107°.

Questions and Answers

What is the hybridization of NH3?+

The hybridization of the central nitrogen atom in NH3 (Ammonia) is sp3.

What is the shape and structure of NH3?+

Although its electron geometry is tetrahedral, the presence of one lone pair on the nitrogen atom distorts the shape, making the actual molecular structure of NH3 Trigonal Pyramidal.

More in Chemistry

Study Smarter with Shinyu.ai

Turn this guide into revision flashcards, a practice exam, or an AI-generated podcast — free, no signup required.