the ties that bind chemical bonding and interactions
TRANSCRIPT
The Ties That Bind
Chemical Bonding and Interactions
Chemical Bonding and Interactions1. Stable Electron Configurations2. Electron-Dot (Lewis) Structures
1. Drawing, Rules for Drawing2. The Octet Rule3. Some Exceptions to the Rule
3. Ionic Bonding1. Naming ionic compounds2. Drawing
4. Covalent Bonding1. Naming covalent compounds2. Drawing3. Electronegativity and Polar Covalent Compounds
5. Molecular Shapes and the VSEPR Theory6. Intermolecular Forces of Attraction
1. H-bonds, Dipole-Dipole, Ion-Dipole, London Dispersion Forces
MOLECULAR GEOMETRY
The VSEPR ModelThe VSEPR Model
Predicting Molecular GeometriesPredicting Molecular Geometries
Cl ClBe
2 atoms bonded to central atom0 lone pairs on central atom 10.1
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The VSEPR ModelThe VSEPR Model
Predicting Molecular GeometriesPredicting Molecular Geometries
10.1
bonding-pair vs. bondingpair repulsion
lone-pair vs. lone pairrepulsion
lone-pair vs. bondingpair repulsion> >
The VSEPR ModelThe VSEPR Model
Molecules with Expanded Valence ShellsMolecules with Expanded Valence Shells
The VSEPR ModelThe VSEPR Model
Molecules with Expanded Molecules with Expanded Valence ShellsValence ShellsTo minimize ee repulsion, lone pairs are always placed in equatorial positions.
The VSEPR ModelThe VSEPR Model
Molecules with Expanded Valence ShellsMolecules with Expanded Valence Shells
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The VSEPR ModelThe VSEPR Model
The VSEPR ModelThe VSEPR ModelMolecules with More than One Central AtomMolecules with More than One Central AtomIn acetic acid, CH3COOH, there are three central atoms.We assign the geometry about each central atom separately.
Predicting Molecular Geometry1. Draw Lewis structure for molecule.
2. Count number of lone pairs on the central atom and number of atoms bonded to the central atom.
3. Use VSEPR to predict the geometry of the molecule.
What are the molecular geometries of SO2 and SF4?
SO O
AB2E
bent
S
F
F
F F
AB4E
distortedtetrahedron
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The VSEPR ModelThe VSEPR Model
Predicting Molecular GeometriesPredicting Molecular GeometriesTo determine the electron pair geometry:
draw the Lewis structure;count the total number of electron pairs around the central atom.arrange the electron pairs in one of the above geometries to minimize e-e repulsion.multiple bounds count as one bonding pair.