Transcript Bonding Theories > 8.3 Molecular Orbitals

8.3
Bonding Theories > Molecular Orbitals
C. Bonding Theory:
1. molecular orbitals: When two atoms combine,
the molecular orbital model assumes that their
atomic orbitals overlap to produce orbitals that
apply to the entire molecule.
a. belongs to a molecule as a whole.
2. bonding orbital: when a covalent bond is
occupied by two electrons.
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8.3 Bonding Theories > Molecular Orbitals
a. sigma bond: two atomic orbitals combine to
form a molecular orbital that is symmetrical
around the axis connecting two atomic nuclei.
b. pi bond ( bond): bonding electrons are found
in sausage-shaped regions above and below the
bond axis of the bonded atoms.
F
F
F--—-F
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8.3
Bonding Theories > Molecular Orbitals
Pi-bonding Molecular Orbital
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8.3 Bonding Theories > VSEPR Theory
3. VSEPR (valence-shell electron-pair
repulsion) theory: repulsion between electron
pairs causes molecular shapes to adjust so that
the valence-electron pairs stay as far apart as
possible.
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8.3
Bonding Theories > VSEPR Theory
a. Nine Possible Molecular Shapes
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8.3
Bonding Theories > Hybrid Orbitals
Hybridization Involving Single Bonds
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8.3
Bonding Theories > Hybrid Orbitals
Hybridization Involving Double Bonds
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8.3
Bonding Theories > Hybrid Orbitals
Hybridization Involving Triple Bonds
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Bonding Theories > Hybrid Orbitals
Simulation 7 Compare sp, sp2, and sp3
hybrid orbitals.
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8.3 Section Quiz.
1. A molecular orbital belongs to a
a. specific atom.
b. molecule as a whole.
c. specific pair of atoms.
d. central atom.
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8.3 Section Quiz.
2. VSEPR theory enables prediction of 3dimensional molecular shape because the
valence electron pairs
a. are attracted to each other.
b. form molecules with only four possible
shapes.
c. stay as far apart as possible.
d. always form tetrahedral shapes.
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8.3 Section Quiz.
3. Orbital hybridization provides information
about
a. both molecular bonding and molecular
shape.
b. both molecular bonding and bond energy.
c. neither molecular bonding nor molecular
shape.
d. neither molecular bonding nor bond
energy.
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