Hybridization

Hybridization: Concept, Types, and Examples

Definition: Hybridization is the process of mixing atomic orbitals of the same atom to form new orbitals called hybrid orbitals. The resulting hybrid orbitals possess distinct shapes and energy levels compared to the original atomic orbitals, and they help in understanding the structure and bonding patterns in molecules.

Need for Hybridization: The concept of hybridization helps explain molecular shapes predicted by the VSEPR theory, bond angles, and the equivalent nature of bonds in molecules like methane (CH₄).

Types of Hybridization:

• sp Hybridization: Involves mixing of one s and one p orbital to form two linearly arranged sp hybrid orbitals.
  Geometry: Linear
  Bond Angle: 180°
  Example: BeCl₂
• sp² Hybridization: Mixing of one s and two p orbitals to form three sp² orbitals in a trigonal planar arrangement.
  Geometry: Trigonal Planar
  Bond Angle: 120°
  Example: BF₃
• sp³ Hybridization: One s and three p orbitals combine to form four sp³ hybrid orbitals.
  Geometry: Tetrahedral
  Bond Angle: 109.5°
  Example: CH₄
• sp³d Hybridization: This involves the combination of one s orbital, three p orbitals, and one d orbital, resulting in the formation of five sp³d hybrid orbitals.
  Geometry: Trigonal Bipyramidal
  Bond Angles: 90° and 120°
  Example: PCl₅
• sp³d² Hybridization: One s, three p, and two d orbitals combine to form six sp³d² orbitals.
  Geometry: Octahedral
  Bond Angle: 90°
  Example: SF₆

Key Points:

• The overall count of orbitals remains unchanged during hybridization.
• It explains equivalent bond formation (e.g., four identical bonds in CH₄).
• d-Orbital involvement is only possible from the 3^rd period onward due to availability of d orbitals.
• Electron promotion (like 2s to 2p) is often the first step before hybridization for bonding.