Section 9-4 Summarize the VSEPR bonding theory. Section 9.4 Molecular Shapes Section 9-4 Summarize the VSEPR bonding theory. atomic orbital: the region around an atom’s nucleus that defines an electron’s probable location Predict the shape of, and the bond angles in, a molecule. Define hybridization. VSEPR model hybridization The VSEPR model is used to determine molecular shape.

Write a paragraph that includes all of the terms above.

Section 9-4 VSEPR Model The shape of a molecule determines many of its physical and chemical properties. Molecular geometry (shape) can be determined with the Valence Shell Electron Pair Repulsion model, or VSEPR model which minimizes the repulsion of shared and unshared atoms around the central atom.

Electron pairs repel each other and cause molecules to be in fixed positions relative to each other. Unshared electron pairs also determine the shape of a molecule. Electron pairs are located in a molecule as far apart as they can be.

Hybridization is a process in which atomic orbitals mix and form new, identical hybrid orbitals. Carbon often undergoes hybridization, which forms an sp3 orbital formed from one s orbital and three p orbitals. Lone pairs also occupy hybrid orbitals.

Single, double, and triple bonds occupy only one hybrid orbital (CO2 with two double bonds forms an sp hybrid orbital).

Section 9-4 Hybridization (cont.)

Section 9-4 Hybridization (cont.)

Hybridization (cont.) Section 9-4

Section 9.4

Electronegativity and Polarity Standard: 2f, 259 Mastering Concepts: 272(80-83) Terms: 259 Practice Problems: 262 (49-53) Cornell Notes: 9.4 Section Assessment: 262(54-57) Labs: 261 Mastering Problems: 272(105-107)

Mastering Concepts: 272(80-83) 80. On what is the VSEPR model based? (9.4) the repulsive nature of electron pairs around a central atom

Mastering Concepts: 272(80-83) 81. What is the molecular shape of each of the following molecules? Estimate the bond angle for each assuming no lone pair. (9.4) A—B linear, 180° b. A—B—A

Mastering Concepts: 272(80-83) c. A—B—A A trigonal planar, 120°

Mastering Concepts: 272(80-83) d. A A—B—A A tetrahedral, 109° Mastering Concepts: 272(80-83)

Mastering Concepts: 272(80-83) 82. What is the maximum number of hybrid orbitals a carbon atom can form? (9.4) four

Mastering Concepts: 272(80-83) 83. Explain the theory of hybridization and determine the number of hybrid orbitals present in the molecule PCl5. (9.4) five identical sp3d orbitals formed

Building VSEPR Lab 261

Electronegativity and Polarity Standard: 2f, 259 Mastering Concepts: 272(80-83) Terms: 259 Practice Problems: 262 (49-53) Cornell Notes: 9.4 Section Assessment: 262(54-57) Labs: 261 Mastering Problems: 272(105-107)

Practice Problems: 262 (49-53) Determine the molecular geometry, bond angle, and type of hybridization for the following. 49. BF3 50. NH4+ 51. OCl2 52. BeF2 53. CF4

Practice Problems: 262 (49-53) Determine the molecular geometry, bond angle, and type of hybridization for the following. 49. BF3 1s 2s 2p Mix and create new Max the # unpaired electrons available for bonding trigonal planar, 120°, sp2 1s sp

Practice Problems: 262 (49-53) Determine the molecular geometry, bond angle, and type of hybridization for the following. 50. NH4+ 1s 2s 2p Mix and create new tetrahedral, 109°, sp3 1s sp

Practice Problems: 262 (49-53) Determine the molecular geometry, bond angle, and type of hybridization for the following. 51. OCl2 1s 2s 2p Mix and create new bent, 104.5°, sp3 1s sp

Practice Problems: 262 (49-53) Determine the molecular geometry, bond angle, and type of hybridization for the following. 52. BeF2 1s 2s 2p Mix and create new linear, 180°, sp 1s sp

Practice Problems: 262 (49-53) Determine the molecular geometry, bond angle, and type of hybridization for the following. 53. CF4 1s 2s 2p Mix and create new tetrahedral, 109°, sp3 1s sp