C7
Atomic Orbitals and Hybridization
Valence Electron Structure of Carbon
Outlined the valence electron configuration of carbon.
Noted the presence of three 2p electrons.
Hybridization Overview
Described the formation of four sp³ hybrid orbitals from the mixture of atomic orbitals.
Clarified that sp³ refers to the name of the resultant hybrid orbitals, not a direct combination of one s and three p orbitals.
Geometry and Arrangement of sp³ Hybrid Orbitals
Shape of sp³ Hybrid Orbitals
Arranged in a tetrahedral shape to maximize the distance between electron domains.
Best arrangement for four electron domains is tetrahedral geometry.
Examples of sp³ Hybridization
Ammonia (NH₃)
Lewis structure shows one lone pair and three bonding groups, totaling four electron domains.
Result: sp³ hybridization due to the four electron domains.
One sp³ orbital contains a lone pair; three overlap with hydrogen 1s orbitals to form bonds.
Water (H₂O)
Lewis structure illustrates two lone pairs and two bonding groups, also totaling four electron domains.
Thus, water is also sp³ hybridized.
Two sp³ orbitals are occupied by lone pairs; two overlap with hydrogen 1s orbitals.
Hybridization of Different Electron Domains
Transition from sp³ to sp² Hybridization
sp³ is applicable for atoms with four electron domains.
sp² is relevant when an atom has three electron domains, requiring three orbitals for bonds or lone pairs.
Formation of sp² Hybrid Orbitals
Electrons are drawn from 2s and two of the 2p orbitals to create three sp² hybrid orbitals.
Retain one 2p orbital unhybridized post-hybridization.
Shape of sp² Hybrid Orbitals
Existence in a trigonal planar geometry with an angle of 120 degrees.
One remaining 2p orbital remains perpendicular to the trigonal plane.
Example of sp² Hybridization
Ethylene (C₂H₄)
Lewis structure showcases that each carbon atom is bonded to three groups: total three electron domains.
Each carbon is sp² hybridized with three sp² hybrid orbitals involved in bonds, and one unhybridized 2p orbital involved in pi bonding.
Bonds are composed of:
Sigma Bond formed via overlap of sp² orbitals.
Pi Bond created through the parallel overlap