AP Chemistry Unit 9: Chemical Bonding, Part II

Goals:

  • To identify the limitations of Lewis structures with respect to explaining chemical bonding
  • To use VSEPR to predict molecular geometry of simple molecules
  • To use Valence Bond Theory to explain bonding issues (ex. bond energy) that Lewis structures cannot

Course Goals and Essential Questions

  • How can we learn about things that are to small to see?
  • What relationships can I construct among basic concepts, skills, and understandings?
  • How can I best assess my own learning and progress?
  • How can I better use technology in my learning?
  • How can I become a better digital citizen?
  • How can I think more divergently, create, innovate?
  • How can I use my experience in chemistry to learn to think and communicate clearly, logically, and critically in preparation for college and a career?

Prior Knowledge

  • Covalent and ionic bonds; valence electrons

 

Prior Skills

  • Draw Lewis Dot Structures for compounds following the octet rule.
  • Write electron configurations for atoms of any element.
Learning Targets Ch. 10.1 Molecular Geometry

Students will know....

  • Valence shell electron pair repulsion theory
  • Names and shapes of basic molecular geometries
  • Electronegativity,

Students will be able to....

  • Identify using the VSEPR model, what category (and thus the corresponding molecular geometry, angle(s) and sketch) a molecular or ion belongs given its formula.
  • Rationalize the observed decrease in angles for AB4E0, AB3E1, and AB2E2 and for AB3E0 and AB2E1.
  • Apply VSEPR model to compounds with more than one central atom.
Learning Targets Ch. 10.2 Dipole Moments

Students will know....

  • dipole, polarity, dipole moment
  • How a microwave oven functions and how the type of chemical bonds present effects the amount of energy absorbed.

Students will be able to....

  • Use the concepts of electronegativity, dipole moments, and VSEPR geometries to identify polar and nonpolar molecules.
Learning Targets Ch. 10.3 Valence Bond Theory

Students will know....

  • Valence Bond theory
  • Hybrid orbitals

Students will be able to....

  • Sketch and justify how potential energy changes versus the interatomic distance for a diatomic molecule.
  • Use Valence Bond theory, hybrid orbitals, and hybridization to explain the geometries predicted by VSEPR model.
Learning Targets Ch. 10.4 Hybridization of Atomic Orbitals

Students will know....

  • hybrid orbitals

Students will be able to....

  • Identify what type of hybrid orbitals are in common compounds and ions.
Learning Targets Ch. 10.5 Hybridization in Molecules Containing Double and Triple Bonds

Students will know....

  • Sigma and pi bonds

Students will be able to....

  • Apply the concepts of sigma and pi bonds and Valence Bond (VB) theory to explain properties of double and triple bonds and the concept of resonance.
Learning Targets Ch. 10.6 Molecular Orbital Theory

Students will know....

  • The limitations of Valence Bond Theory and how Molecular Orbital theory accounts for those limitations.

Students will be able to....

  • State what physical property of oxygen gas is not accounted for by Valence Bond theory but is in Molecular Orbital (MO) theory.
  • Explain the difference between bonding and anti-bonding orbitals using the concepts of constructive and destructive interference of waves.
  • Show molecular orbital energy diagrams for first and second row diatomic molecules identifying sigma and pi bonding and anti-bonding molecular orbitals.
Learning Targets Ch. 10.7 Molecular Orbital Configurations

Students will know....

Students will be able to....

  • Write molecular orbital electron configurations for simple diatomics.
  • Relate molecular orbital energy diagrams to bond order, bond length and bond strength.
Learning Targets Ch. 10.8 Delocalized Molecular Orbitals
  • Describe resonance using the Molecular Orbital theory.
  • Suggest the significance of the discoveries of fullerenes and nanotubes.
Daily Learning Activities
Day 29
  • Chapter 10.1-10.3 Using Lewis structures as a basis for molecular geometry
Day 30
  • Molecular modeling - geometry (dry lab handout)
Day 31
  • Quiz - Lewis structure, molecular geometry, polarity
  • 10.4-10.6Valence Bond Theory and hybrid orbitals

Links and Resources

Textbook, Chapter 10


L. C. Lee 1990-2012
Creative Commons License
This work by Luann Christensen Lee is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.
Based on a work at www.chemistar.com.

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