CHEMISTRY 110 EXAM 2
March 2, 2011
FORM A
--------------------------------------------------------------------------------1. What is the molecular geometry of the ICl4− ion?
A.
B.
C.
D.
E.
tetrahedral
square planar
octahedral
trigonal pyramidal
trigonal bipyramidal
--------------------------------------------------------------------------------2. What is the mass % of oxygen in the molecule shown below?
A.
B.
C.
D.
E.
37.8%
42.8%
58.6%
62.2%
82.0%
---------------------------------------------------------------------------------2
---------------------------------------------------------------------------------3. Which intermolecular forces act between the molecules of
formaldehyde, CH2O?
i.
ii.
iii
A.
B.
C.
D.
E.
dispersion
dipole
H-bonding
i only
i and ii
i and iii
ii and iii
all three
---------------------------------------------------------------------------------4. Which of the following organic molecules can be
classified as an alkene?
i
ii
A.
B.
C.
D.
E.
iii
iv
v
i and iv
ii only
ii and v
iii and v
ii, iii, and v
--------------------------------------------------------------------------------3
--------------------------------------------------------------------------------5. What is the hybridization of the nitrogen atom in glutamic acid
(shown below)? Note: lone pairs are not shown explicitly.
O
O
HO
OH
NH2
A.
B.
C.
D.
E.
sp2
sp
sp3
sp3d
sp3d2
--------------------------------------------------------------------------------6. What is the hybridization of the bromine atom in BrF3?
A.
B.
C.
D.
E.
sp
sp2
sp3
sp3d
sp3d2
--------------------------------------------------------------------------------4
-------------------------------------------------------------------------------7. The molecular formula of caffeine is C8H10N4O2. A sample
was analyzed and found to contain 0.325 mg of oxygen.
What is the mass of hydrogen in the sample?
A.
B.
C.
D.
E.
0.102 mg
0.122 mg
0.650 mg
1.63 mg
3.25 mg
--------------------------------------------------------------------------------8. Which of the following has a molecular shape that is most
similar to the shape of the ammonium ion?
A.
B.
C.
D.
E.
NH2–
NH3
N2H4
BF4–
XeF4
--------------------------------------------------------------------------------5
--------------------------------------------------------------------------------9. Which of the following molecules has a non-zero dipole
moment?
A.
B.
C.
D.
E.
OF2
BF3
CO2
C6H6 (benzene)
SF6
--------------------------------------------------------------------------------10. Which one of these samples has the smallest number of
atoms?
A.
B.
C.
D.
E.
159.8 g of Br2
6.02 × 1022 molecules of glycine C2H5O2N
44 g of CO2
6.02 × 1023 molecules of water H2O
6.54 g of Zn
--------------------------------------------------------------------------------6
--------------------------------------------------------------------------------11. Rank the bond angles in order of increasing size.
1
H
H
H
H
3
C
C
C
C
H
H
N
H
H
2
O
C
C
4
OH
A. 1 < 2 < 3 < 4
B. 4 < 2 < 3 < 4
C. 1 = 2 < 3 = 4
D. 1 = 2 < 4 < 3
E. 2 < 1 < 4 < 3
--------------------------------------------------------------------------------12. Rank the following molecules in order of increasing
carbon-carbon bond length.
C2H4 C2H2 C2H6
1
2
3
A. 1 < 2 < 3
B. 2 < 3 < 1
C. 3 < 2 < 1
D. 2 < 1 < 3
E. 1 < 3 < 2
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7
--------------------------------------------------------------------------------13. How many σ and how many π bonds are present in the
following molecule?
OH
O
A.
B.
C.
D.
E.
σ = 8, π = 2
σ = 4, π = 2
σ = 16, π = 0
σ = 14, π = 2
σ = 14, π = 1
--------------------------------------------------------------------------------14. Which functional group is not present in the organic
compound shown below?
A.
B.
C.
D.
E.
aromatic
ketone
carboxylic acid
aldehyde
alcohol
--------------------------------------------------------------------------------8
--------------------------------------------------------------------------------15. Which of the following molecules are structural isomers?
1
3
2
4
A. 1 and 2 only
B. 2 and 4 only
C. 1, 2 and 4 only
D. 1 and 3 only
E. 1 and 4 only
--------------------------------------------------------------------------------16. Which of the following molecules are polar?
Cl
ii
i
A.
B.
C.
D.
E.
O
OH
iii
i only
ii only
i and ii
ii and iii
all three are polar
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9
--------------------------------------------------------------------------------17. What properties of H2O can be attributed to hydrogen bonding?
I. Liquid water is colorless.
II. The density of ice is lower than that of liquid water.
III. Water has a higher boiling point than H2S.
A.
B.
C
D.
E.
I only
III only
I and III
II and III
All of the above can be attributed to hydrogen bonding
--------------------------------------------------------------------------------18. Which of the following will have H-bonding between
molecules in the pure liquid phase?
H O
H C C O H
H
i
A.
B.
C.
D.
E.
H
H C N H
ii
H O
H C C H
H
iii
i only
ii only
iii only
i and ii
i, ii, and iii
--------------------------------------------------------------------------------10
--------------------------------------------------------------------------------19. Which pairs of molecules have the correct boiling point
(bp) trend?
i.
ii
iii
A.
B.
C.
D.
E.
bp of CSe2 > bp of CO2
bp of O2 > bp of H2
bp of SiH4 > bp of SnH4
i only
ii only
iii only
i and iii
i and ii
--------------------------------------------------------------------------------20. Given the structure below, what is the molecular weight of
methyl salicylate, a key ingredient in heat ointments that
promote healing by increasing capillary blood flow?
O
OH O
A.
B.
C.
D.
E.
121 g/mol
133 g/mol
137 g/mol
144 g/mol
152 g/mol
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11
--------------------------------------------------------------------------------21. Arrange the following in order of decreasing melting point.
CaO
A.
B.
C.
D.
E.
Ar
H2O
CaO > H2O > Ar
CaO > Ar > H2O
H2O > CaO > Ar
H2O > Ar > CaO
Ar > H2O > CaO
--------------------------------------------------------------------------------22. Vitamin C is a compound that contains only C, H and O. It
has a molar mass of 176.12 g/mol. When a 1.000 g
sample is burned, 1.50 g of CO2 and 0.410 g of water are
collected after complete combustion. What is the
molecular formula of Vitamin C?
A.
B.
C.
D.
E.
C6H8O6
C3H4O3
C2H4O
C7H12O5
C8H16O4
---------------------------------------------------------------------------------12
--------------------------------------------------------------------------------23. Rank these in order of increasing polarity.
CH3F, CH3Cl, CF4
A. CH3F < CH3Cl < CF4
B. CH3Cl < CH3F < CF4
C. CH3F < CF4 < CH3Cl
D. CF4 < CH3F < CH3Cl
E. CF4 < CH3Cl < CH3F
--------------------------------------------------------------------------------24. A molecule has the Lewis structure shown below. What is
the molecular geometry and identity of element E?
F
F
E
F
A.
B.
C.
D.
E.
E = Xe, trigonal planar
E = Kr, T-shaped
E = Cl, trigonal planar
E = Se, see saw
E = Br, T-shaped
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13
--------------------------------------------------------------------------------25. Which of the following organic molecules have the same
empirical formula as cyclohexane?
---------------------------------------------------------------------------------26. Which one of the following will have delocalized π bonding?
O
OH
O
i
A.
B.
C.
D.
E.
ii
S
O
iii
i only
i and ii
i and iii
ii and iii
all three
---------------------------------------------------------------------------------14
--------------------------------------------------------------------------------27. Which of the following is/are geometric isomer(s) of the
structure below?
H
C C
H
H 3C
H
C C
H
CH3
CH3
1
A.
B.
C.
D.
E.
H
C C
H
CH2 CH3
H
2
CH3
H 3C
C C
H
CH3
H
3
1 and 2
1 and 3
1
2
3
---------------------------------------------------------------------------------28. What is the molecular formula of the alcohol shown below?
A.
B.
C.
D.
E.
C5H9O
C3H6O2
C4H9O
C4H10O
C4H8O2
---------------------------------------------------------------------------------End of Test
---------------------------------------------------------------------------------15
CHEMISTRY 110 EXAM 2
March 2, 2011
Answer Key
FORM A
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
B
C
B
D
C
D
A
D
A
E
E
D
D
C
A
D
D
D
E
E
A
A
E
E
A
C
E
D
16