Chemistry: A Molecular Approach (Tro) Chapter 10 Chemical Bonding II: Molecular Shapes, Valance Bond Theory, and Molecular OrbitalTheory 1) Determine the electron geometry (eg) and molecular geometry(mg) of BCl 3. A) eg=trigonal planar, mg=trigonal planar B) eg=tetrahedral, mg=trigonal planar C) eg=tetrahedral, mg=trigonal pyramidal D) eg=trigonal planar, mg=bent E) eg=trigonal bipyramidal, mg= trigonal bipyramidal Answer: A 2) Determine the electron geometry (eg), molecular geometry (mg), and polarity of SO 2. A) eg=tetrahedral, mg=bent, polar B) eg=trigonal planar, mg=bent, polar C) eg=linear, mg=linear, nonpolar D) eg=tetrahedral, mg=tetrahedral, nonpolar E) 1 eg=trigonal pyramidal, mg=trigonal pyramidal, polar Answer: B 3) Determine the electron geometry (eg), molecular geometry (mg), and polarity of SO 3. A) eg=tetrahedral, mg=trigonal pyramidal, polar B) eg=tetrahedral, mg=tetrahedral, nonpolar C) eg=trigonal planar, mg=trigonal planar, nonpolar D) eg= trigonal bipyramidal, mg=trigonal planar, polar E) eg=trigonal pyramidal, mg=bent, nonpolar Answer: C 4) Determine the electron geometry (eg) and molecular geometry (mg) of CO 32⁻. A) eg=tetrahedral, mg=tetrahedral B) eg=tetrahedral, mg=trigonal pyramidal C) eg=trigonal planar, mg=bent D) eg=trigonal planar, mg=trigonal planar E) eg=tetrahedral, mg=trigonal planar Answer: 2 D 5) Determine the electron geometry (eg) and molecular geometry (mg) of SiF 4. A) eg=tetrahedral, mg=trigonal pyramidal B) eg=octahedral, mg=square planar C) eg=trigonal bipyramidal, mg=trigonal pyramidal D) eg=tetrahedral, mg=bent E) eg=tetrahedral, mg=tetrahedral Answer: E 3 6) Determine the electron geometry (eg) and molecular geometry (mg) of PF 5. A) eg=trigonal bipyramidal, mg=trigonal bipyramidal B) eg=octahedral, mg=octahedral C) eg=trigonal bipyramidal, mg=tetrahedral D) eg=tetrahedral, mg=trigonal pyramidal E) eg=trigonal planar, mg=octahedral Answer: A 7) Determine the electron geometry (eg) and molecular geometry (mg) of BrF 3. A) eg=trigonal planar, mg=trigonal planar B) eg=trigonal bipyramidal, mg= T-shape C) eg=trigonal planar, mg=bent D) eg=trigonal bipyramidal, mg=see-saw E) eg=tetrahedral, mg=trigonal pyramidal Answer: B 8) Determine the electron geometry (eg) and molecular geometry (mg) of ICl 2⁻. A) 4 eg=tetrahedral. A) eg=tetrahedral. mg=linear D) eg=trigonal bipyramidal. mg=bent B) eg=tetrahedral. mg=linear E) eg=tetrahedral. mg=linear D) eg=trigonal bipyramidal. mg=bent Answer: D 10) Determine the electron geometry (eg) and molecular geometry (mg) of XeF4. mg=bent B) eg=linear. mg=linear Answer: C 9) Determine the electron geometry (eg) and molecular geometry (mg) of XeF2. mg=linear C) eg=tetrahedral. mg=trigonal pyramidal C) eg=trigonal bipyramidal. A) eg=trigonal bipyramidal. mg=tetrahedral B) 5 . mg=trigonal planar E) eg=octahedral. eg=linear. mg=bent D) eg=trigonal bipyramidal. mg=tetrahedral E) eg=octahedral. eg=linear C) eg=tetrahedral. mg=square planar Answer: E 11) How many of the following molecules are polar? BrCl3 A) 1 B) 2 C) 3 D) 4 E) 0 Answer: A CS2 SiF4 SO3 6 . 12) How many of the following molecules are polar? XeCl2 A) 0 COF2 PCl4F SF6 B) 3 C) 1 D) 2 E) 4 Answer: B 13) How many of the following molecules are polar? XeO2 A) 1 SiCl2Br2 C2Br2 SeCl6 B) 4 C) 2 D) 3 E) 0 Answer: 7 . BCl3 A) I < II = III B) II < III < I C) I < II < III D) II < I < III E) I < III < II Answer: 8 II. BIF2 III.C 14) How many of the following molecules are polar? PCl5 A) 2 B) 0 C) 1 D) 3 E) 4 Answer: D 15) Place the following in order of increasing dipole moment. I. BClF2 COS XeO3 SeBr2 . E 9 . trans-CHCl=CHCI III. but is nonpolar. cis-CHCl=CHCl A) III > I > II II. I.16) Place the following in order of decreasing dipole moment. A) HCN B) CF4 C) SeBr4 D) ICl3 E) Both B and C are nonpolar and contain a polar covalent bond. cis-CHF=CHF B) II > I > III C) I > III > II D) II > III > I E) I = III > II Answer: A 17) Choose the compound below that contains at least one polar covalent bond. Answer: B 18) 10 . nonpolar B) eg=tetrahedral. nonpolar C) eg=tetrahedral. Answer: C 19) Determine the electron geometry. mg=linear. molecular geometry and polarity of XeF6 . molecular geometry and polarity of N 2O (N central). polar E) eg=trigonal planar. A) eg=linear. polar Answer: D 20) Determine the electron geometry. A) 11 . mg=linear. A) GeH2Br2 B) SCl2 C) AsCl5 D) CF2Cl2 E) All of the above are nonpolar and contain a polar covalent bond. but is nonpolar. polar D) eg= linear. mg=bent. mg=bent.Choose the compound below that contains at least one polar covalent bond. mg=linear. nonpolar B) eg=trigonal bipyramidal. mg=octahedral. nonpolar E) eg=octahedral. mg=trigonal pyramidal. polar C) eg=trigonal bipyramidal. nonpolar C) eg=octahedral. mg=square planar.eg=trigonal bipyramidal. mg=trigonal bipyramidal. molecular geometry and polarity of TeCl 6. mg=octahedral. mg=tetrahedral. mg=trigonal bipyramidal. mg=see-saw. mg=trigonal bipyramidal. nonpolar Answer: E 21) Determine the electron geometry. A) eg=octahedral. nonpolar B) eg=tetrahedral. mg=see-saw. polar E) eg=tetrahedral. polar D) eg=trigonal bipyramidal. polar Answer: A 12 . polar D) eg=octahedral. polar Answer: C 24) Consider the molecule below. nonpolar B) eg=tetrahedral. nonpolar C) eg=tetrahedral. mg=bent. Determine the molecular geometry at each of the 2 labeled carbons. mg=trigonal planar. mg=tetrahedral. 13 . nonpolar E) eg=linear. mg=trigonal planar. nonpolar B) eg=octahedral. polar D) eg=tetrahedral.22) Determine the electron geometry (eg). polar D) eg=trigonal bipyramidal. A) eg=trigonal bipyramidal. molecular geometry and polarity of HBrO 2 . polar C) eg=trigonal planar. A) eg=trigonal planar. nonpolar Answer: B 23) Determine the electron geometry. mg=linear. mg=trigonal pyramidal. mg=square planar. molecular geometry(mg) and polarity of XeO3. mg=trigonal pyramidal. mg=trigonal planar. mg=linear. nonpolar E) eg=octahedral. C2 = linear B) C1 = trigonal planar.A) C1 = tetrahedral. C2 = sp3d2 E) 14 . C2 = sp2 C) C1 = sp2. C2 = tetrahedral E) C1 = trigonal pyramidal. C2 = sp3d D) C1 = sp3d. C2 = sp3d B) C1 = sp. Determine the hybridization at each of the 2 labeled carbons. C2 = see-saw Answer: D 25) Consider the molecule below. A) C1 = sp3. C2= bent C) C1 = bent. C2 = trigonal planar D) C1 = trigonal planar. C2 = sp3 Answer: E 15 .C1 = sp2. 2=sp3. 2=tetrahedral. 3=trigonal pyramidal Answer: A 27) Consider the molecule below. A) 1=trigonal planar. Determine the hybridization at each of the 3 labeled atoms. 2=tetrahedral.26) Consider the molecule below. 2=tetrahedral. 3=sp2 B) 1=sp2. Determine the molecular geometry at each of the 3 labeled atoms. 2=sp3. 3=tetrahedral D) 1=tetrahedral. 3=tetrahedral C) 1=trigonal planar. 2=tetrahedral. A) 1=sp2. 3=trigonal pyramidal B) 1=tetrahedral. 3=trigonal planar E) 1=trigonal planar. 3=sp3 C) 16 . 2=trigonal pyramidal. 3=sp2 E) 1=sp.1=sp3. SeO2 A) SeCl6 < SeF2 < SeO2 B) SeF2 < SeO2 < SeCl6 C) SeF2 < SeCl6 < SeO2 D) SeO2 < SeF2 < SeCl6 E) SeCl6 < SeO2 < SeF2 Answer: A SeCl6 SeF2 17 . 2=sp3. 3=sp2 Answer: B 28) Place the following in order of increasing Se-X bond angle. 3=sp3 D) 1=sp3. 2=sp2. where X represents the outer atoms in each molecule. 2=sp3. 29) Place the following in order of increasing A-F bond angle. PF3 A) PF3 < OF2 < PF4⁺ B) OF2 < PF3 < PF4⁺ C) OF2 < PF4⁺ < PF3 D) PF4⁺ < OF2 < PF3 E) PF4⁺ < PF3 < OF2 Answer: B 30) Place the following in order of decreasing A-X bond angle. where A represents the central atom and X represents the outer atoms in each molecule. N2 O A) NCl3 > NO2⁻ > N2O B) NO2⁻ > N2O > NCl3 C) N2O > NO2⁻ > NCl3 D) NCl3 > N2O > NO2⁻ E) NCl3 NO2⁻ OF2 PF4⁺ 18 . where A represents the central atom in each molecule. where A represents the central atom and X represents the outer atoms in each molecule. CS2 A) CS2 = SCl2 > CF4 B) SCl2 > CF4 > CS2 C) CF4 > CS2 > SCl2 D) CS2 > CF4 > SCl2 E) CF4 > CS2 = SCl2 Answer: D 32) Place the following in order of increasing A-X bond angle.N2O > NCl3 > NO2⁻ Answer: C 31) Place the following in order of decreasing A-X bond angle. where A represents the central atom and X represents the outer atoms in each molecule. HCN A) H2O = H3O⁺ < HCN B) H3O⁺ < H2O < HCN C) HCN < H3O⁺ < H2O D) 19 H2O H3O⁺ CF4 SCl2 . H2O < HCN < H3O⁺ E) H2O < H3O⁺ < HCN Answer: E 20 . 33) Draw the Lewis structure for the molecule C3H6. 0 pi E) 6 sigma. 2 pi C) 9 sigma. 2 pi E) 8 sigma. 2 pi D) 13 sigma. 4 pi B) 11 sigma. How many sigma and pi bonds does it contain? CH3CHCHCO2H A) 9 sigma. 0 pi C) 9 sigma. How many sigma and pi bonds does it contain? A) 8 sigma. 2 pi Answer: A 34) Consider the following compound. 1 pi D) 7 sigma. 2 pi Answer: B 35) 21 . 1 pi B) 9 sigma. Draw the Lewis structure for the molecule C3H4. 2 pi D) 10 sigma. 2 pi Answer: C 36) A molecule containing a central atom with sp3 hybridization has a(n) __________ electron geometry. A) linear B) trigonal bipyramidal C) octahedral D) tetrahedral E) bent Answer: D 37) A molecule containing a central atom with sp3d hybridization has a(n) __________ electron geometry. How many sigma and pi bonds does it contain? A) 7 sigma. 0 pi C) 6 sigma. 1 pi B) 8 sigma. 0 pi E) 8 sigma. A) 22 . tetrahedral B) linear C) octahedral D) trigonal planar E) trigonal bipyramidal Answer: E 38) A molecule containing a central atom with sp3d2 hybridization has a(n) __________ electron geometry. A) octahedral B) trigonal bipyramidal C) tetrahedral D) trigonal planar E) trigonal pyramidal Answer: A 23 . What is the hybridization on the O atom? A) sp B) sp3 C) sp2 D) sp3d E) sp3d2 Answer: B 40) Draw the Lewis structure for SO3.39) Draw the Lewis structure for OF2. What is the hybridization on the S atom? A) sp B) sp3 C) sp2 D) sp3d E) sp3d2 Answer: C 41) 24 . What is the hybridization on the Br atom? A) 25 .Draw the Lewis structure for BrO4⁻. What is the hybridization on the Br atom? A) sp B) sp3d2 C) sp3d D) sp3 E) sp2 Answer: D 42) Draw the Lewis structure for SF6. What is the hybridization on the S atom? A) sp B) sp2 C) sp3 D) sp3d E) sp3d2 Answer: E 43) Draw the Lewis structure for BrF5. sp3d2 B) sp3d C) sp3 D) sp2 E) sp Answer: A 44) Draw the Lewis structure for BrCl3. What is the hybridization on the Br atom? A) sp3d2 B) sp3d C) sp3 D) sp2 E) sp Answer: B 26 . 45) How many of the following molecules have sp hybridization on the central atom? C2Cl2 A) 0 CO2 O3 H2O B) 1 C) 2 D) 3 E) 4 Answer: C 46) How many of the following molecules have sp2 hybridization on the central atom? HCN A) 4 SO2 OCl2 XeCl2 B) 3 C) 2 D) 1 E) 0 Answer: 27 . D 47) How many of the following molecules have sp3 hybridization on the central atom? XeCl4 A) 0 B) 4 C) 3 D) 2 E) 1 Answer: E 48) How many of the following molecules have sp3d hybridization on the central atom? SiCl4 A) 2 B) 0 C) 4 D) 1 E) 3 Answer: 28 BrF5 AsF5 BrF3 CH4 SF4 C2H2 . A 29 . 49) How many of the following molecules have sp3d2 hybridization on the central atom? SeCl6 A) 1 XeF4 IF5 AsCl5 B) 3 C) 0 D) 2 E) 4 Answer: B 50) How many of the following molecules contain at least one pi bond? C2H6 A) 0 Cl2CO C2Cl4 SeS3 B) 1 C) 3 D) 4 E) 2 Answer: 30 . C 51) Which of the following statements is TRUE? A) The total number of molecular orbitals formed doesn't always equal the number of atomic orbitals in the set. E) All of the above are true. B) A bond order of 0 represents a stable chemical bond. D) Electrons placed in antibonding orbitals stabilize the ion/molecule. one molecular orbital will be lower in energy than the two separate atomic orbitals and one molecular orbital will be higher in energy than the separate atomic orbitals. C) When two atomic orbitals come together to form two molecular orbitals. Answer: C 31 . 52) Use the molecular orbital diagram shown to determine which of the following is most stable. A) F2 B) F22⁺ C) Ne22⁺ D) O22⁺ E) F22⁻ Answer: D 32 . 33 . Answer: D 34 .53) Use the molecular orbital diagram shown to determine which of the following are paramagnetic. A) O22⁻ B) Ne22⁺ C) O22⁺ D) F22⁺ E) None of the above are paramagnetic. 35 . 54) Use the molecular orbital diagram shown to determine which of the following is most stable. A) C22⁺ B) N22⁺ C) B2 D) C22⁻ E) B22⁺ Answer: D 36 . 37 . A) B22⁺ B) B22⁻ C) N22⁺ D) C22⁻ E) B2 Answer: E 38 .55) Use the molecular orbital diagram shown to determine which of the following are paramagnetic. An antibonding orbital is usually higher in energy than the two separated atoms and has a node in the internuclear region. what is an antibonding orbital? Answer: An antibonding orbital is formed when 2 orbitals destructively interfere with one another. 57) Use molecular orbital theory to determine whether He22⁺ or He2⁺ is most stable.56) According to molecular orbital theory. Draw the molecular orbital diagram for each and explain your answer. The He 22⁺ ion is more stable since it has a higher bond order (bond order =1) than He2⁺ (bond order = 1/2). Answer: The MO diagram should show He22⁺ with 2 electrons in the bonding orbital and the MO diagram of He 2⁺ should show 2 electrons in the bonding MO and 1 electron in the antibonding MO. 39 . the second 2 C's are linear and the last C is tetrahedral. The first 2 C's are trigonal planar. An example is CF4 where there are four polar bonds. 59) Is it possible for a molecule to be nonpolar even though it contains polar bonds? Explain your answer and give an example. Answer: Yes. Match the following. CH2CHCCCH3 Answer: The sketch should show all of the appropriate multiple bonds. the next 2 C's are sp hybridized and the last C is sp3 hybridized. but the dipoles sum to 0 making the molecule nonpolar.58) Determine the molecular geometry about each interior atom in the following structure. the molecule will be nonpolar. The first 2 C's are sp 2 hybridized. 60) Determine the hybridization about each interior atom in the following structure. If the molecular geometry causes all of the dipoles to cancel. The polarity of a molecule depends on the molecular geometry and whether or not all of the dipoles (polar bonds) cancel one another. Sketch the 3 dimensional structure and label the interior atoms with their corresponding hybridization. 61) CH2F2 A) octahedral electron geometry 62) BCl3 B) sp2 hybridized central atom 63) BeF2 C) 40 . CH2CHCCCH3 Answer: The sketch should show all of the appropriate multiple bonds. Sketch the 3 dimensional structure and label the interior atoms with the corresponding molecular geometry. but contains no polar bonds. but contains a polar covalent bond F) polar. G) see-saw molecular geometry 61) C 62) E 63) D 64) G 65) A 41 .polar 64) SF4 D) sp hybridized central atom 65) XeCl4 E) nonpolar.