2nd Quarter General Chemistry I - Molecular Geometry PDF

2 QUARTER GENERAL CHEMISTRY I ND MOLECULAR GEOMETRY Describe the geometry of simple compounds (STEM_GC11CB-IId-g-81) Determine the polarity of simple molecules (STEM_GC11CB-IId-g-82) 1. Apply the Valence Shell Electron Pair Repulsion Theory to predict the geometry of molecules. 2. determine whe...

2 QUARTER GENERAL CHEMISTRY I ND MOLECULAR GEOMETRY Describe the geometry of simple compounds (STEM_GC11CB-IId-g-81) Determine the polarity of simple molecules (STEM_GC11CB-IId-g-82) 1. Apply the Valence Shell Electron Pair Repulsion Theory to predict the geometry of molecules. 2. determine whether of a bond is ionic, nonpolar or polar covalent based on the electronegativity difference 3. Predict the polarity of molecule STIRRING UP YOUR IMAGINATION What is molecular geometry? How does the Valence Shell Electron Pair Repulsion (VSEPR) theory help in predicting the molecular geometry of a molecule? KEY CONCEPTS: MOLECULAR GEOMETRY KEY CONCEPTS: VSEPR (Valence Shell Electron Pair Repulsion Theory ) KEY CONCEPTS: Five Basic Electron Group Arrangement KEY CONCEPTS: Table 2. Molecular Shapes for CentralAtom with Two, Three and Four Bonded KEY CONCEPTS: Table 2. Molecular Shapes for CentralAtom with Two, Three and Four Bonded Example: Predict the molecular geometry of BeCl2. a. Draw the Lewis structure of the molecule. b. How many electron groups are present? Ans. 2 electron groups Example: Predict the molecular geometry of BeCl2. c. How many bond pair/s are present around the central atom? Ans. 2 bond d. How manypairs lone pair/s are present around the central atom? Ans. 0 lone pair Example: Predict the molecular geometry of BeCl2. e. How will these electron groups orient themselves in order to minimize repulsion? Ans. 2-0 will give BeCl2 a linear electron group geometry and a linear shape. f. What is the bond angle in Cl-Be-Cl? Ans. 180 Example: Predict the molecular geometry of BCl3. a. Draw the Lewis structure of the molecule. b. How many electron groups are present? Ans. 3 electron groups Example: Predict the molecular geometry of BeCl3. c. How many bond pair/s are present around the central atom? Ans. 3 bond d. How manypairs lone pair/s are present around the central atom? Ans. 0 lone pair Example: Predict the molecular geometry of BeCl3. e. How will these electron groups orient themselves in order to minimize repulsion? Ans. The combination between the bonded atoms and lone pairs, 3-0 will give BCl3 a trigonal planar electron group geometry and a trigonal planar shape. f. What is the bond angle? Ans. 120 Example: : Predict the molecular geometry of SO2. a. Draw the Lewis structure of the molecule. b. How many electron groups are present? Ans. 3 electron groups Example: Predict the molecular geometry of SO2.. c. How many bond pair/s are present around the central atom? Ans. 2 bond d. How manypairs lone pair/s are present around the central atom? Ans. 1 lone pair Example: Predict the molecular geometry of SO2. e. How will these electron groups orient themselves in order to minimize repulsion? Ans. The combination between the bonded atoms and lone pairs, 2-1 will give SO2 a trigonal planar electron group geometry but the molecular geometry is bent shape. f. What is the bond angle? Ans.