I. PRACTICE EXERCISES 1: Given the following elements: N and O a) Write the electronic configuration of each atom in their Ground and Excited States b) Identify the valence electrons and the covalency numbers (GS & ES) c) Write the Lewis Dot Structure of these atoms (GS & ES) d) Identify the pure orbitals occupied by the valence electrons (GS & ES) B. Based on the ES electronic configuration of N and O; a) Write all the possible hybrid orbitals that can be formed in each atom. b) Write the Lewis Dot Structure. c) Identify the hybrid orbitals in the structure. Example Practice A: C Atomic number = 6 Atomic mass = 12 #neutron=6 #proton= 6 #electron = 6 Ground State electronic configuration: 1s2 2s2 2p2 valence electrons = 4 2s2 2px1 2py1 covalency number = 2 2s2 2px1 2Py1 lp σ π Lewis Dot Structure: . .py1 π px1. C : s2 lp lp:C =σ Excited State electronic configuration: 1s2 2s1 2p3 valence electrons = 4 2s1 2px1 2py1 2pz1 covalency number=4 2s1 2px1 2py1 2pz1 Lewis Dot Structure: .py1 .π px1. C . s1 σ . C . σ . .π pz1 Example Practice B: sp Hybrid: 1s2 (2sp)1 (2sp)1 2py1 2pz1 σ σ π π π π py π pz π : C : sp σ : C : sp σ σ σ py π pz π pz π spσ= C = sp σ spσ - C Ξspσ py π sp2 Hybrid: 1s2 (2sp2)1 (2sp2)1 (2sp2)1 2pz1 σ σ σ π pz π pz π sp2σ . C : sp2 σ sp2σ - C = sp2σ . sp2σ l sp2σ sp3 Hybrid: 1s2 (2sp3)1 (2sp3)1 (2sp3)1 ( 2sp3)1 σ σ σ σ sp3 . sp3 σ l sp3 . C . sp3 sp3 σ - C - sp3 sp3 . l sp3 σ II. PRACTICE EXERCISE 2: Identify the hybrid orbitals used in the given molecules. H H H H 2 l 3 l 4 l 5 l ..6 H 1- C 7- C8 = C 9- C10 - O - H l l .. H H Example: ..6 O : H 4 ll 5 l 1. H - C ; s-sp2σ 2. C -C ; sp2-sp3σ H_1___C 2 C 3H 3. C - H ; sp3 - s σ l 4. C-O ; sp2 - sp2σ H 5. C - O ; pz - pz π 6. : O sp2 lone pair III. PRACTICE EXERCISE 3. Answer the following questions in the provided space provided: 1. Which is longer—a C–H bond or a C–O bond? 2. Which is shorter—an N–H bond or a C–H bond? 3. Arrange the following bonds from least polar to most polar: H-F, H-N, H-O, H-Cl