chemical bonding and molecular structure chapter 12 sec 12.8 - 12.10
TRANSCRIPT
![Page 1: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/1.jpg)
Chemical Bondingand Molecular Structure
Chapter 12Sec 12.8 - 12.10
![Page 2: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/2.jpg)
Goals:
1. To use Lewis Structures as a way to predict the geometry of Molecules
2. Determine if molecules are polar or nonpolar
![Page 3: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/3.jpg)
VSEPR Model
• Valence Shell Electron Pair Repulsion Model
• Bonds (pairs of electrons) attempt to move as far away as possible from one another in a molecule
![Page 4: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/4.jpg)
This explains the Geometry of H2O
Water is a “bent” molecule, because
of the lone pairs around the central
Oxygen atom
![Page 5: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/5.jpg)
Various Geometry of Molecules
See Examples on Next Slides
(Hand-Out)
![Page 6: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/6.jpg)
![Page 7: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/7.jpg)
![Page 8: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/8.jpg)
Polar or Non-polar Molecule?
A molecule may have polar covalent
bonds and not be polar overall
?????????
Geometry must also be considered
![Page 9: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/9.jpg)
Ammonia (NH3) is polar
1. The bonds between hydrogen and nitrogen are polar covalent (∆EN = .87)
2. Pyramidal geometry of molecule points charges toward N
![Page 10: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/10.jpg)
Carbon Dioxide is Non-polar
Even though the bonds between carbon and oxygen are polar covalent (∆EN = 1.0), the pull of electrons is in equal and opposite directions because CO2 is linear
![Page 11: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/11.jpg)
Water is Wacky!
Water has some strange properties due to its structure
![Page 12: Chemical Bonding and Molecular Structure Chapter 12 Sec 12.8 - 12.10](https://reader035.vdocuments.site/reader035/viewer/2022081513/5697bfd81a28abf838caf184/html5/thumbnails/12.jpg)