Question 1

Boron nitride is being investigated in frontier research directed at producing novel electronic devices. If you used the following energy level diagram for the molecular orbitals of boron nitride, BN, what would you predict? 
(I) Boron nitride is diamagnetic.
(II) Boron nitride has a bond order of 2.
(III) Boron nitride is paramagnetic.
(IV) The bond in BN- is stronger than the bond in BN.

Accepted Answer

A)  I and II 
B)  II and III 
C)  I, II, and IV 
D)  III 
E)  IV

Question 2

Draw a structure showing the geometry of the molecule in the following group that is nonpolar: HF; NH₃; BF₃; CHCl₃; CO.

Accepted Answer

The answer of Draw a structure showing the geometry of...

Question 3

Which statement regarding a pi bond between two carbon atoms is correct?

Accepted Answer

A)  The region of high electron density lies along the bond axis connecting the nuclei of the two atoms. 
B)  Can be described by the overlap of sp hybrid orbitals from each atom. 
C)  Can be described by the overlap of sp2 hybrid orbitals from each atom. 
D)  Can be described by the overlap of p atomic orbitals from each atom. 
E)  Can be described by the overlap of a p atomic orbital from one atom with an sp2 hybrid orbital from the other atom.

Question 4

Identify the hybridization of the atomic orbitals on carbon atoms labeled 1, 2, and 3. The hydrogen atoms and lone pair electrons are not shown in the diagram.

Accepted Answer

The answer of Identify the hybridization of the atomic orbitals...

Question 5

Which electron-pair geometry has the lowest electron-electron repulsive forces?

Accepted Answer

A)  linear 
B)  trigonal planar 
C)  tetrahedral 
D)  trigonal bipyramidal 
E)  octahedral

Question 6

Identify the hybridization of atomic orbitals for atoms N1, N2, C1, C2, and C3 in caffeine, which is shown below. Explain why you think this molecule is planar or nonplanar.

Accepted Answer

The answer of Identify the hybridization of atomic orbitals for...

Question 7

Which of the following compounds has a square pyramid shape?

Accepted Answer

A)  ICl3 
B)  BrF5 
C)  PCl5 
D)  PH3 
E)  SiF4

Question 8

What is the geometry of the ClF4- ion?

Accepted Answer

A)  square planar 
B)  square pyramidal 
C)  trigonal pyramidal 
D)  tetrahedral 
E)  seesaw

Question 9

Which of the following has the largest bond angle?

Accepted Answer

A)  CF4 
B)  NF3 
C)  F2O 
D)  NF2- 
E)  NH3

Question 10

Which type of molecular orbital contains a node perpendicular to the axis connecting two atomic nuclei?

Accepted Answer

A)  "F1F1F1S1F1F1F10" 
B)  "F1F1F1S1F1F1F10" 
C)  "F1F1F1S1F1F1F10*" 
D)  s 
E)  p

Question 11

Which of the following ions is linear?

Accepted Answer

A)  SCN- 
B)  NO2- 
C)  SO32- 
D)  NH4+ 
E)  SO22-

Question 12

Which of the following is a planar molecule?

Accepted Answer

A)  NH3 
B)  PCl5 
C)  KrF4 
D)  CH3COOH 
E)  SiH4

Question 13

Which of the following molecules has a bond order that is less than one?

Accepted Answer

A)  F2 
B)  He2- 
C)  Ne22+ 
D)  N2 
E)  O22-

Question 14

Determine the molecular geometry of CF2Cl2.

Accepted Answer

A)  linear 
B)  bent 
C)  trigonal bipyramidal 
D)  tetrahedral 
E)  trigonal pyramidal

Question 15

Which one of the following statements regarding molecular orbitals for diatomic molecules is not correct?

Accepted Answer

A)  An atomic orbital on one atom combines with an atomic orbital on the other atom to form two molecular orbitals. 
B)  2p atomic orbitals only form F1F1F1S1F1F1F10 and F1F1F1S1F1F1F10* molecular orbitals. 
C)  2s atomic orbitals only form F1F1F1S1F1F1F10 and F1F1F1S1F1F1F10F1F1F1S1F1F1F10* atomic orbitals. 
D)  "F1F1F1S1F1F1F10" orbitals are symmetric with respect to rotation around the internuclear axis; F1F1F1S1F1F1F10 orbitals do not have this symmetry. 
E)  A bonding molecular orbital describes the build-up of negatively charged electrons between the nuclei.

Question 16

Which statement concerning benzene is not correct?

Accepted Answer

A)  A second Lewis structure is needed to describe benzene. 
B)  All the F1F1F1S1F1F1F10 bonds originate from p atomic orbitals. 
C)  Benzene does not have a dipole moment. 
D)  The carbon atomic orbitals are sp2 hybridized. 
E)  Benzene has both long and short carbon-carbon bonds.

Question 17

Which of the following compounds has the same molecular shape as CCl3H?

Accepted Answer

A)  SiF4 
B)  KrF4 
C)  SF4 
D)  C2H4 
E)  C2H2

Question 18

Which bond angle is the smallest?

Accepted Answer

A)  H - C - H in CH4 
B)  H - C - H in C2H4 
C)  H - C - H in H2CO 
D)  H - C - C in C2H2 
E)  H - C - O in H2CO

Question 19

Use energy levels of diatomic molecules derived from molecular orbital theory to predict the magnetic properties of the oxygen molecule O2 and the peroxide anion O22-.

Accepted Answer

A)  oxygen (paramagnetic); peroxide (paramagnetic) 
B)  oxygen (paramagnetic); peroxide (diamagnetic) 
C)  oxygen (diamagnetic); peroxide (paramagnetic) 
D)  oxygen (diamagnetic); peroxide (diamagnetic) 
E)  Neither have magnetic properties, only metals have magnetic properties.

Question 20

Which of the following compounds has the largest dipole moment?

Accepted Answer

A)  CH2Cl2 
B)  CH3Cl 
C)  CHCl3 
D)  CCl4 
E)  CH4

Exam 9: Molecular Geometry and Bonding Theories

Draw a structure showing the geometry of the molecule in the following group that is nonpolar: HF; NH₃; BF₃; CHCl₃; CO.

Which statement regarding a pi bond between two carbon atoms is correct?

Identify the hybridization of the atomic orbitals on carbon atoms labeled 1, 2, and 3. The hydrogen atoms and lone pair electrons are not shown in the diagram.

Which electron-pair geometry has the lowest electron-electron repulsive forces?

Identify the hybridization of atomic orbitals for atoms N1, N2, C1, C2, and C3 in caffeine, which is shown below. Explain why you think this molecule is planar or nonplanar.

Which of the following compounds has a square pyramid shape?

What is the geometry of the ClF₄^- ion?

Which of the following has the largest bond angle?

Which type of molecular orbital contains a node perpendicular to the axis connecting two atomic nuclei?

Which of the following ions is linear?

Which of the following is a planar molecule?

Which of the following molecules has a bond order that is less than one?

Determine the molecular geometry of CF₂Cl₂.

Which one of the following statements regarding molecular orbitals for diatomic molecules is not correct?

Which statement concerning benzene is not correct?

Which of the following compounds has the same molecular shape as CCl₃H?

Which bond angle is the smallest?

Use energy levels of diatomic molecules derived from molecular orbital theory to predict the magnetic properties of the oxygen molecule O₂ and the peroxide anion O₂²^-.

Which of the following compounds has the largest dipole moment?

Exam 9: Molecular Geometry and Bonding Theories

Draw a structure showing the geometry of the molecule in the following group that is nonpolar: HF; NH3; BF3; CHCl3; CO.

Which statement regarding a pi bond between two carbon atoms is correct?

Identify the hybridization of the atomic orbitals on carbon atoms labeled 1, 2, and 3. The hydrogen atoms and lone pair electrons are not shown in the diagram.

Which electron-pair geometry has the lowest electron-electron repulsive forces?

Identify the hybridization of atomic orbitals for atoms N1, N2, C1, C2, and C3 in caffeine, which is shown below. Explain why you think this molecule is planar or nonplanar.

Which of the following compounds has a square pyramid shape?

What is the geometry of the ClF4- ion?

Which of the following has the largest bond angle?

Which type of molecular orbital contains a node perpendicular to the axis connecting two atomic nuclei?

Which of the following ions is linear?

Which of the following is a planar molecule?

Which of the following molecules has a bond order that is less than one?

Determine the molecular geometry of CF2Cl2.

Which one of the following statements regarding molecular orbitals for diatomic molecules is not correct?

Which statement concerning benzene is not correct?

Which of the following compounds has the same molecular shape as CCl3H?

Which bond angle is the smallest?

Use energy levels of diatomic molecules derived from molecular orbital theory to predict the magnetic properties of the oxygen molecule O2 and the peroxide anion O22-.

Which of the following compounds has the largest dipole moment?

Draw a structure showing the geometry of the molecule in the following group that is nonpolar: HF; NH₃; BF₃; CHCl₃; CO.

What is the geometry of the ClF₄^- ion?

Determine the molecular geometry of CF₂Cl₂.

Which of the following compounds has the same molecular shape as CCl₃H?

Use energy levels of diatomic molecules derived from molecular orbital theory to predict the magnetic properties of the oxygen molecule O₂ and the peroxide anion O₂²^-.