Chapter 9
Covalent Bonding:
Orbitals
Section 9.1
Hybridization and the Localized Electron Model
Hybridization
• Mixing of orbitals to form equal orbitals for
bonding.
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Section 9.1
Hybridization and the Localized Electron Model
Exercise
Draw the Lewis structure for methane, CH4.
 What is the shape of a methane molecule?
tetrahedral
H
H C H
H
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Section 9.1
Hybridization and the Localized Electron Model
Concept Check
What is the valence electron configuration of
a carbon atom?
2s22p2
s
p
How can carbon bond to 4 hydrogen atoms?
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Section 9.1
Hybridization and the Localized Electron Model
Four equal orbitals are formed.
sp3 hybrid
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Section 9.1
Hybridization and the Localized Electron Model
sp3 Hybridization
• Combination of one s and three p orbitals.
• Whenever a set of equivalent tetrahedral atomic
orbitals is required by an atom, the atom
becomes sp3 hybridized.
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Section 9.1
Hybridization and the Localized Electron Model
An Energy-Level Diagram Showing the Formation of Four sp3
Orbitals
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Section 9.1
Hybridization and the Localized Electron Model
Examples
1. Be in BeCl2
2. B in BCl3
3. P in PCl5
4. S in SF6
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Section 9.1
Hybridization and the Localized Electron Model
Exercise
Draw the Lewis structure for C2H4 (ethylene)?
 What is the hybridization of the carbon atom?
H
H
H
C C
H
sp2
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Section 9.1
Hybridization and the Localized Electron Model
Example
#3
#1
#2
What is the hybidization for each of the numbered atoms?
#1 sp2
#2 sp3
#3 sp3
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Section 9.1
Hybridization and the Localized Electron Model
Concept Check
Determine the hybridization of the central
atom for each of the following molecules:
NH3
SO2
KrF2
CO2
ICl5
NH3 – sp3
SO2 – sp2
KrF2 – sp3d
CO2 – sp
ICl5 – sp3d2
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