1 / 105

Chapter 10 Chemical Bonding II

Chapter 10 Chemical Bonding II. Lewis Structure  Molecular Structure. Structure determines chemical properties. Electron domain/group: area where electrons appear in Lewis structures. It can be electron lone pairs, single bonds, double bonds, triple bonds, or single electrons.

mikayla-mccray
Download Presentation

Chapter 10 Chemical Bonding II

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 10 Chemical Bonding II

  2. Lewis Structure  Molecular Structure Structure determines chemical properties

  3. Electron domain/group: area where electrons appear in Lewis structures. It can be electron lone pairs, single bonds, double bonds, triple bonds, or single electrons. H2O, NH3, CH4, O2, N2, SCl2, CCl4, PCl3, NO+, NH4+, CO, CO2

  4. Valence Shell Electron Pair Repulsion (VSEPR) model The lowest energy arrangement of a given number of electron domains is the one that minimizes the repulsions among them. The shape of ABn molecules or ions depend on the number of electron domains surrounding the central A atom. number of electron domains: 2 to 6

  5. Know how to spell the names!

  6. How to predict geometry of a molecule? • Draw the Lewis structure of the molecule or ion, and count • the number of electron domains around the central atom. • Determine the electron domain arrangement by arranging the • electron domains about the central atom so that the repulsions • among them are minimized. • 3) Use the arrangement of the bonded atoms to determine the • molecular geometry. CO2

  7. BF3, NO3−,H2CO

  8. Electron domains for multiple bonds exert a greater repulsion force on adjacent electron domains than do electron domains for single bonds. lone pair-lone pair > lone pair-bonding pair > bonding pair- bonding pair

  9. SO2 Bent or V-shaped 119° Electron domain arrangement is not necessarily the same as the molecular structure.

  10. CH4

  11. NH3

  12. H2O

  13. PCl5

  14. SF4 To minimize repulsion, electron lone pairs are always placed in equatorial positions for trigonal bipyramidal geometry.

  15. BrF3

  16. XeF2

  17. SF6

  18. BrF5

  19. XeF4

  20. Polarity of a molecule

  21. How to quantify the polarity of a bond? Dipole moment

  22. + − Dipole Dipole has a magnitude and a direction — vector Magnitude (length) of a dipole — dipole moment μ = qr q — charge, r — distance between + and − charge

  23. H — F dipole dipole moment of a bond ≠ 0 ↔ polar bond dipole moment of a bond = 0 ↔ nonpolar bond

  24. The Pauling Electronegativity Values

  25. Polarity of a molecule dipole moment of a molecule ≠ 0 ↔ polar molecule dipole moment of a molecule = 0 ↔ nonpolar molecule dipole of a molecule = sum of all the bond dipoles

  26. v = v1 + v2 v1 v3 = v2 v2

  27. SO3

  28. SO3 = 120° = Net dipole moment = 0, nonpolar molecule

  29. CCl4 = = 109.5° Net dipole moment = 0, nonpolar molecule

  30. Polarity of a molecule depends on the polarity of its bonds AND the geometry of the molecule.

  31. NH3

  32. How are electrons shared in covalent bonds? Valence Bond Theory Molecular Orbital Theory

  33. Valence Bond Theory: Orbital Overlap as a Chemical Bond

  34. CH4

  35. CH4

  36. 4 electron domains tetrahedral arrangement sp3 hybridization

  37. NH3

  38. H2O sp3 on O

More Related