Chemistry 400
Chapter 10 Homework Problems: VSEPR, Shapes, Valence Bonding and Molecular Orbital Theories
1.
Lewis Structure
A. CO2
B. NO3–
C. NH2Cl
D. SO42–
E. BrCN
A. CHCl3
B. H2CO
C. NH2Cl
D. PO43–
E. SeF5–
Hybridization on
central atom
e– geometry
Molecular geometry
Approx. Bond angles
Polar or non-polar
(don't worry about
ions)
Number of σ bonds
Number of π bonds
Total lone pairs in the
entire molecule
Number of
nonbonding electron
pairs on the central
atom
2.
Lewis Structure
Hybridization
e– geometry
Molecular geometry
Approx. Bond angles
Polar or non-polar
(don't worry about
ions)
Number of σ bonds
Number of π bonds
Total lone pairs in the
entire molecule
Number of
nonbonding electron
pairs on the central
atom
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3. Draw the orbital overlap diagram for CH2CH2. Your diagram should include the type of each atomic orbital (s, p, d, sp2, etc.,) and
whether the overlap forms a sigma or pi orbital.
4. Draw the orbital overlap diagram for CH4. Your diagram should include the type of each atomic orbital (s, p, d, sp2, etc.,) and
whether the overlap forms a sigma or pi orbital.
5. Draw the orbital overlap diagram for CH3CHO. Your diagram should include the type of each atomic orbital (s, p, d, sp2, etc.,) and
whether the overlap forms a sigma or pi orbital.
6. Draw the Lewis structure and orbital overlap diagram for the NO molecule.
7. Draw the Lewis structure and orbital overlap diagram for the CO molecule. Then create a version of the orbital overlap diagram that
is ACTUALLY three dimensional.
8. Draw the Lewis structure and orbital overlap diagram for the CO2 molecule. Then create a version of the orbital overlap diagram
that is ACTUALLY three dimensional.
9. Draw one possible structure for C4H7NO. This structure should have all neutral carbons with 4 bonds, all neutral nitrogens with
three bonds and all neutral oxygens with two bonds. ("Neutral" means FC=0.)
10. Draw one possible structure for C5H6O. This structure should have all neutral carbons with 4 bonds, all neutral nitrogens with
three bonds and all neutral oxygens with two bonds. ("Neutral" means FC=0.)
11. Draw one possible structure for C5H9N. This structure should have all neutral carbons with 4 bonds, all neutral nitrogens with
three bonds and all neutral oxygens with two bonds. ("Neutral" means FC=0.)
12. Draw one possible structure for C6H11NO. This structure should have all neutral carbons with 4 bonds, all neutral nitrogens with
three bonds and all neutral oxygens with two bonds. ("Neutral" means FC=0.)
For each of the following covalent molecules, answer the questions about the molecule. In each case, answering the questions will be
aided by determining the electron arrangements and shapes of the molecules in question.
13. Consider the molecule BrF5
A. What is/are the bond angles in the molecule?
C. Are the bonds in the molecule polar?
B. What is the molecular geometry around the bromine atom?
D. Is the overall molecule polar?
14. Consider the molecule SF6
A. What is the electron geometry around sulfur?
B. What is the hybridization on the sulfur atom?
C. Are the bonds in the molecule polar?
D. Is the overall molecule polar?
15. Consider the molecule CH2F2
A. What is the molecular geometry?
B. What is the hybridization on the carbon atom?
C. Is the overall molecule polar?
D. Sketch the molecule (indicating any dipoles).
16. Consider the molecule PF5
A. What are the bond angles in the molecule?
B. What is the molecular geometry around the phosphorus atom?
C. Are the bonds in the molecule polar?
D. Is the overall molecule polar?
17. Consider the ion ClF6+
A. What is the electron geometry around chlorine?
B. What is the hybridization on the sulfur atom?
C. Are the bonds in the molecule polar?
D. Sketch the molecule (indicating any dipoles).
18. Consider the ion NH3Cl+
A. What is the molecular geometry?
B. What is the hybridization on the nitrogen atom?
C. Is the overall ion polar?
D. Sketch the ion (indicating any dipoles).
19. Consider the ion SO42–
A. What are the bond angles in the molecule?
B. What is the molecular geometry around the sulfur atom?
C. Are the bonds in the molecule polar?
D. Sketch the ion ((indicating any dipoles).
20. Consider the molecule NH3
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A. What is the electron geometry around nitrogen?
B. What is the hybridization on the nitrogen atom?
21. The molecular orbital energy diagram for the
valence orbitals of the NO molecule and the NO–
ion is shown to the right. Use this diagram to
answer the following questions.
A. Fill in all of the electrons for the NO
molecule.
B. What is the bond order in NO?
C. What is the bond order in NO–?
D. Is NO– diamagnetic, or is it
paramagnetic? How can you tell?
E. Which has the larger bond distance,
NO or NO–?
C. What is the molecular geometry?
D. Are the bonds in the molecule polar?
N atom
Energy
2p
2s
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NO
O atom
2p
2s
22. The molecular orbital energy diagram for the
valence orbitals of the CN molecule and the CN–
ion is shown to the right. Use this diagram to
answer the following questions.
A. Fill in all of the electrons for the CN
molecule.
B. What is the bond order in CN?
C. What is the bond order in CN–?
D. Is CN– diamagnetic, or is it
paramagnetic? How can you tell?
E. Which has the larger bond distance,
CN or CN–?
C atom
Energy
CN
2p
2s
N atom
2p
2s
23. A d orbital and a p orbital can combine to form molecular orbitals in several different ways. Draw a sketch of the overlap between
these two atomic orbitals that would produce each of the following molecular orbitals.
A. a pi bonding MO
B. a sigma bonding MO
24. Two p orbitals can combine to form molecular orbitals in several different ways. Draw a sketch of the overlap between these two
atomic orbitals that would produce each of the following molecular orbitals.
A. a pi bonding MO
B. a sigma antibonding MO
25. For each of the following molecules, make a list of the molecules that are (i) polar, (ii) nonpolar and (iii) ionic.
A. H2O
B. CH4
C. CH3CH2OH
D. CH3Cl
E. Na2SO4
F. HCl
G. C6H6
H. CH3COCH3
I. CCl4
26. For each of the following molecules, make a list of the molecules that are (i) polar, (ii) nonpolar and (iii) ionic.
A. NH3
B. H2O
C. CH3CH2CH3
D. NH4Cl
E. Na2SO4
F. CH3Cl
G. C6H6OH
H. CH3COOH
I. LiNO3
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27. Consider the molecule:
4
8
1
5
2
7
3
6
What are the approximate bond angles in the structure?
∠1=
∠2=
∠3=
∠4=
What are the hybridizations of the indicated atoms?
Atom 5:
Atom 6:
Atom 7:
Atom 8:
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