Topic F: Molecular Structure
- Page ID
- 170026
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WHAT YOU SHOULD BE ABLE TO DO WHEN YOU HAVE FINISHED THIS TOPIC:
General Covalent Bonding Concepts
- Understand the relationship between potential energy and internuclear distance.
- Understand a covalent bond in terms of potential energy.
- Recognize that there are two models used to describe covalent bonding: (1) valence bond theory and (2) molecular orbital theory.
Localized Electron Model of Covalent Bonding
- Draw reasonable Lewis structures for small molecules and common polyatomic ions.
- Determine bond order.
- Determine bond polarity.
- Apply the concept of bond energies to estimate \(\Delta\)H for any reaction.
- Understand the relationship between bond order, bond distance, and bond energy.
- Use VSEPR Theory to predict the 3D molecular geometry.
- Determine if a molecule is polar.
- Use resonance structures to show electron delocalization. Use formal charges to determine major and minor resonance contributors.
- Use atomic orbital overlap to model a covalent bond. (Valence Bond Theory)
- Use orbital hybridization to rationalize orbital geometry with the observed bond angles.
- Identify and describe a sigma bond and a pi bond in terms of orbital overlap.
- Overall, predict the following for a given Lewis structure:
- The molecular geometry for a central bonding atom, including typical bond angles.
- Whether the molecular geometry is likely to be distorted.
- The orbital geometry and corresponding orbital hybridization (sp, sp2, sp3, etc.) that will align with the bond geometry for a central bonding atom.
- Whether or not the molecule is polar.
Delocalized Electron Model of Covalent Bonding
- Use molecular orbitals to model a covalent bond. (Molecule Orbital Theory)
- Use MO energy diagrams to determine bond order and magnetic properties of a molecule.
- Draw sketches of the molecular orbitals for diatomic molecules that are formed from linear combinations of two atomic orbitals, and identify each as bonding or antibonding.