a) Draw Lewis structures for each of the compounds below. Be sure to show all bonding and non-bonding valence electrons. Also, clearly indicate any formal charges on atoms. b) Consider the molecular geometry information given for each compound below: based on this information, specify the orbitals that each atom could use in σ- and à-bonding (sp², sp³, p, etc.) and for holding non-bonding electron pairs. Explain how your orbital assignments are consistent with the observed geometries. H₂CO (formaldehyde) HCO-angle 120⁰ CH3CO₂ (acetate anion) HCC-angle ≈ 109⁰ CCO-angle OCO≈ 120° DCH=CHBr(1-bromo-2-deuterioethylene) (two isomers) (all atoms are coplanar) (CH3)2SO (dimethylsulfoxide, DMSO) HCS-angle CSO CSC≈ 109⁰ ≈

Calculate the number of valence electrons Molecule # 5 SiF?- Draw the Lewis Structure below Draw the three-dimensional structure of the molecule using the "wedge and dash" notation. The molecular geometry is: This molecule is polar nonpolar (Circle your choice.) Our logic for this choice is: The formal charge on Si is The formal charge on F is The hybridization of Si is Estimate F-Si-F bond angle Molecule # 6 CC2F2 Draw the Lewis Structure below Calculate the number of valence electrons Draw the three-dimensional structure of the molecule using the "wedge and dash" notation. The molecular geometry is: This molecule is polar nonpolar (Circle your choice.) Our logic for this choice is: The formal charge on C is The formal charge on Cl/F is The hybridization of C is Estimate F-C-Cl bond angle

Consider the structure Y-X-Y If the symbol X represents a central atom, Y represents outer atoms, and Z represents lone pairs on the central atom, the structure could be abbreviated as XY₂Z₂. 2 Classify each molecule according to its shape. Linear XY₂Z2 Bent (≈ 120°) XY3Z2 Bent (≈ 109°) XY₂Z3 Trigonal pyramidal XY₂Z T-shaped Answer Bank XY3Z See-saw XY4Z2 XY-Z Square planar Square pyramidal XY Z

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