Hybridization

            Definition:       A process in which atomic orbitals of different energy and shape are mixed together to form a new set of equivalent orbitals of the same energy and shape is called             Hybridization.

˜      Hybridization is the rearrangement of orbitals on a single atom or ion.

˜      Those orbitals can rearrange (Hybridized) which have low energy difference.

˜      The number of orbitals obtained (Hybridized) is always equal to the number of orbitals mixed.

˜      The hybrid orbital is used for the formation of sigma bond.

˜      The number of hybrid orbitals can be determine by the number of sigma bonds and lone pair of electrons around the central atom. This is also caleed steric number

Steric number = number of bonded electrons+ number of lone pair of electrons.

Types of Hybridization

(1)        SP₃ – Hybridization:-             When one S and 3 – P orbitals mixed up together form four SP₃ hybrid orbitals. 

˜      SP₃ – hybridization occur when carbon is bonded to four other atoms like in CH₄, CCl₄, CHCl₃

SP₃ – hybrid orbitals exhibit 25% S and 75% P–orbitalscharacter, because they combine in the ration of 1:3.

˜      When SP₃ hybridization occur, the electronic geometry of the molecule become tetra hedral.

˜      The angle between the bonded electron is 109.5^O.

˜      All the bonds are sigma bond in SP₃ – hybridization.

Example:-       Formation of CH₄, H₂O, NH₃

2.         SP₂ – Hybridization:- When one S and 2P orbitals mixed up together form SP₂ hybrid orbitals.

˜      This hybridization occur when carbon is bonded to three other atoms like

                   H              H                     H

                        C = C            ,                     C = 0

                   H              H                     H      

˜      SP₂ hybrid orbital show 33% S and 67% P characters.

˜      When SP₂ hybridization occur, the geometry adopt by molecule is trigonal.

˜      The angle between bonded electrons is 120^O.

˜      When SP₂ hybridization occur in C, it form p bond by the sidewise overlapping of un-hybridized P-orbitals.

Example:-       Formation of C₂H₄:-     Two carbon of C₂H₄ is SP₂ hybridized. 

3;         SP hybridization;        when one s and one p orbitals mixed together to form two      hybrid orbitals.

☻;This hybridization occur when carbon is bonded to two other atoms or form two sigma bonds.

♥          sp hybridized orbital show 50% S and 50% P characters

♥          The geometry of the molecule will be linear.

♥          The angle between the bonded electrons will be 180⁰_.

♥          Two sigma bonds will be present.

Example; C₂H₂ (Ethyne)