Lecture on Hybridization States and Geometries

Key Concepts

• Hybridization: Process of mixing atomic orbitals to form new hybrid orbitals suitable for pairing electrons.
• Geometries: Shapes formed based on hybridization states, influencing bond angles.

Example Analysis

• Objective: Identify hybridization states and predict geometries for all atoms except hydrogen.

Example 1

Carbon Atoms

1. Carbon with Double Bond

   • Hybridization: SP²
   • Geometry: Trigonal planar, bond angles ≈ 120°

2. Carbon with Single Bonds

   • Hybridization: SP³
   • Geometry: Tetrahedral, bond angles ≈ 109.5°

3. Carbon with Triple Bond

   • Hybridization: SP
   • Geometry: Linear, bond angle = 180°

Bonds Analysis

• Sigma Bonds: Total of 10
• Pi Bonds: Total of 3

Example 2: Diethyl Ether

1. Carbon with Single Bonds

   • Hybridization: SP³
   • Geometry: Tetrahedral

2. Oxygen Atom

   • Hybridization: SP³
   • Geometry: Bent due to lone pairs

Example 3

Carbon and Nitrogen

1. Carbon with Double Bond

   • Hybridization: SP²
   • Geometry: Trigonal planar

2. Carbon with Single Bonds

   • Hybridization: SP³
   • Geometry: Tetrahedral

3. Nitrogen Atom

   • Hybridization: SP³
   • Geometry: Trigonal pyramidal

Steric Number

• Definition: Sum of sigma bonds and lone pairs of electrons.
• Use: Helps determine hybridization states.

Examples Using Steric Number

• Steric Number 3: SP² hybridization (3 hybrid orbitals)
• Steric Number 4: SP³ hybridization (4 hybrid orbitals)

Additional Notes

• Hydrogen: Excluded in geometry discussions due to single bond with no hybridization necessity.
• Practice: Emphasized to strengthen understanding of organic hybridization.