Download Project Advance Chemistry 106 Sample Questions

Chemistry 116: General Chemistry
Syracuse University Project Advance
Final Exam, Spring 2008
Name
Date
_______
[Gas constant = 0.00831 kJ/mol K; 1 faraday = 96500 J/V mol e- ]
1. The first-order reaction, SO2Cl2 → SO2 + Cl2, has a half-life of 8.75 hours at 593 K. How long
will it take for the concentration of SO2Cl2 to fall to 12.5% of its initial value?
A.
B.
C.
D.
E.
0.165 h
3.22 h
6.06 h
15.3 h
26.2 h
2. Which is the correct equilibrium expression for the following reaction?
2Ag(s) + Cl2
A. Keq 
B. K eq 
C. K eq 
D. K eq 
2AgCl(s)
[AgCl]
[Ag]2 [Cl2 ]
[2AgCl]
[2Ag][Cl2 ]
[AgCl]2
[Ag]2 [Cl2 ]
1
[Cl2 ]
E. Keq  [Cl2]
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Spring 2008 Final Exam
3. If G˚ > 0 for the reaction A
A.
B.
C.
D.
E.
B, one can then conclude that
there will be more A than B at equilibrium
there will be more B than A at equilibrium
there will be only A at equilibrium
there will be only B at equilibrium
we also need S˚ in order to predict the equilibrium distribution
4. Given the following Ka values for the following acids:
HF
HNO2
HOBr
HCN
6.8 x 10-4
4.5 x 10-4
2.5 x 10-9
4.9 x 10-10
Which of the following is the weakest acid?
A.
B.
C.
D.
E.
HF
HNO2
HOBr
HCN
NH4+
5. Balance the following equation, in an acidic solution (already set up as such) and indicate the
coefficients of H2S and H2O.
___ MnO4- + ___ H2S + ___ H+  ___ Mn2+ + ___ S + ___ H2O
A.
B.
C.
D.
E.
5, 8
2, 6
3, 8
5, 10
2, 4
6. Tritium is most readily distinguished from the other two isotopes of hydrogen due to its
A.
B.
C.
D.
E.
chemical reactions
atomic volume
radioactivity
electron affinity
acidity
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Spring 2008 Final Exam
7. Calculate the pH of an aqueous solution prepared by dissolving 5.61 g of KOH pellets in water
and diluting to a final volume of 0.50 L.
A.
B.
C.
D.
E.
0.30
1.30
13.00
13.30
13.70
8. The decay of
A.
B.
C.
D.
E.
85
36 Kr
to
85
37 Rb
occurs through the emission of a(n) ________.
alpha particle
beta particle
neutron
proton
positron
9. The CC–H bond angle in an alkyne is most nearly
A.
B.
C.
D.
E.
180˚
120˚
109.5˚
90˚
60˚
10. How many grams of Cadmium metal will be plated out of solution that contains Cd+2 using a
current of 1.25 amperes applied for 15 minutes?
A.
B.
C.
D.
E.
18.3 g
0.66 g
1.31 g
2.62 g
35.2 g
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Spring 2008 Final Exam
11. NO reacts with bromine according to the following equation:
2NO(g) + Br2(g)  2NOBr(g)
The following data were experimentally obtained for this reaction:
Exp
#
0.10
0.10
0.20
Initial [NO]
Initial [Br2]
0.10
0.20
0.20
1.3 × 10–7
5.2 × 10–7
1.0 × 10–6
Initial rate of
NOBr formation
0.80 M/sec
1.60 M/sec
6.40 M/sec
Determine the rate expression for this reaction.
A.
B.
C.
D.
E.
rate = k[NO][Br2]
rate = k[NO]2[Br2]
rate = k[NO][Br2]2
rate = k[NO]2[Br2]2
not enough information
12. In the following reaction: Pb + 2Ag+  Pb+2 + 2Ag , the Ag+ is
A.
B.
C.
D.
E.
reduced, and the oxidation number changes from +1 to 0
reduced, and the oxidation number changes from +2 to 0
oxidized, and the oxidation number changes from 0 to +1
oxidized, and the oxidation number changes from +1 to 0
None of the above.
13. To balance the nuclear equation
235
92U
+ 0n1 
139
56Ba
+ x + 3 0 n1
X must be
A. 33As97
B. 56Ba94
C. 36Br93
D. 36Kr94
E. 2He4
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Spring 2008 Final Exam
14. Consider the following chemical system at equilibrium.
6H2O(g) + 2N2(g) + heat
4NH3(g) + 3O2(g)
Which of the following stresses would shift the equilibrium to the left?
A.
B.
C.
D.
E.
increasing the concentration of O2
increasing the reaction temperature
increasing the concentration of H2O
decreasing the concentration of NH3
increasing the concentration of N2
15. The value of the ion product constant for water, Kw, at 60˚C is 9.6 × 10-14. Compute [H3O+]
for a neutral aqueous solution at 60˚C. Is an aqueous solution with a pH = 6.51 acidic, basic
or neutral at 60˚C?
A.
B.
C.
D.
E.
3.1 × 10-7, acidic
3.1 × 10-7, neutral
3.1 × 10-7, basic
3.1 × 10-8, basic
3.1 × 10-8, acidic
16. The IUPAC name of the compound, CH3CH2CH=CHCH2CH3, having two H’s on the same
“side” of the double bond is
A.
B.
C.
D.
E.
cis-2-hexane
cis-3-hexyne
cis-3-hexanal
cis-2-hexene
cis-3-hexene
17. A reaction is spontaneous when
A.
B.
C.
D.
E.
G˚ is negative or E˚ is positive.
G˚ is negative or E˚ is negative.
G˚ is positive or E˚ is negative.
G˚ is positive or E˚ is positive.
G˚ is negative, H˚ is negative, and E˚ is negative.
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Spring 2008 Final Exam
18. Uric acid, a weak monoprotic acid (HA), is a metabolic end product and is excreted from the
body in urine. The acid dissociation constant of uric acid is Ka = 4.0  10-6 M. The pH of a
urine sample is 6.00. What is the ratio of urate ion to uric acid in the urine?
A.
B.
C.
D.
E.
0.25
1.5
4.0
6.0
24
19. The correct name of the following compound is
O
OR
A.
B.
C.
D.
E.
C–C–C–C–C
2-pentaketone
methyl propyl ether
2-quinone
2-pentanone
methyl butanoate
20. The half-life of carbon-14 is 5730 years. What is the approximate age of a fossil with a
carbon-14 ratio to carbon 1/64 that of a living organism of the same species?
A.
B.
C.
D.
E.
28650 years
5730 years
34,380 years
17190 years
22920 years
21. The equilibrium constant, Kp, for the reaction 2HgO(s)   2Hg(l) + O2(g) is 1.2 x 10-30
Calculate the Kp for the reaction 1/2O2(g) + Hg(l)   HgO(s)
A.
B.
C.
D.
E.
9.1 x 1014
8.3 x 1029
1.1 x 10-15
-1.1 x 10-15
4.2 x 1029
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Spring 2008 Final Exam
22. Radionuclides which have too low of a neutron/proton ratio generally decay through
________.
A.
B.
C.
D.
E.
beta emission
electron capture or positron emission
gamma ray emission
alpha emission
neutron absorption
23. When the concentrations of the reactants are increased, the rate of the reaction increases. This
is best explained by
A.
B.
C.
D.
E.
an increase in the frequency of the molecular collisions.
an increase in the fraction of molecules that have enough energy to react.
an increase in the rate constant.
an increase in the kinetic energy of the molecules.
an increase in the average potential energy of the molecules.
24. Assume that the reaction
H2O(g) + CO(g)
H2(g) + CO2(g)
occurs in an ideal mixture of ideal gases. At 700 K, Kp = 5.10. What is G˚ at this
temperature?
A.
B.
C.
D.
E.
-9.48 kJ/mol
-4.12 kJ/mol
0 kJ/mol
9.48 kJ/mol
29.7 kJ/mol
25. In the compounds, NO, NH3, N2H4, NO2, and HNO3, nitrogen appears in ___ different
oxidation states.
A.
B.
C.
D.
E.
1
2
3
4
5
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Spring 2008 Final Exam
26. Calculate the pH of a solution prepared by dissolving 0.15 moles of benzoic acid (HBz) and
0.30 moles of sodium benzoate (NaBz) in 1.00 L of solution. (Ka of HBz = 6.5 x 10-5).
A.
B.
C.
D.
E.
2.51
3.89
4.49
10.11
12.67
27. What is the pH of a solution in which 25.0 mL of 0.010 M NaOH are added to 10.0 mL of
0.020 M HCl?
A.
B.
C.
D.
E.
10.23
10.58
10.84
11.15
11.32
28. Given the decomposition reaction,
PCl5(g)
PCl3(g) + Cl2(g)
when 0.84 moles of PCl5 is placed in a 3.0 L flask, it was found that when the reaction
reaches equilibrium, 0.72 moles of PCl5 still remains. What is the value of the equilibrium
constant for this reaction?
A.
B.
C.
D.
E.
0.0067
0.020
0.12
0.62
0.72
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Spring 2008 Final Exam
29. The standard reduction potentials in volts for Zn+2 and Fe+2 are -0.76 and -0.44
respectively. Determine the value of the Eocell for a voltaic cell in which the overall reaction is
Zn + Fe+2  Fe + Zn+2
A.
B.
C.
D.
E.
0.32 volts
-0.32 volts
1.20 volts
 volts
-0.76 volts
30. The first-order isomerization reaction: cyclopropane → propene, has a rate constant of 1.10 ×
10–4 s–1 at 470°C and 5.70 × 10–4 s–1 at 500ºC. What is the activation energy, Ea, for the
reaction?
A.
B.
C.
D.
E.
46 kJ/mol
110 kJ/mol
260 kJ/mol
380 kJ/mol
520 kJ/mol
31. What kind of radiation will travel through an electric field on a pathway that will remain
unaffected by the field?
A.
B.
C.
D.
E.
a proton
a gamma ray
an electron
an alpha particle
none of the above
CHE 116
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Spring 2008 Final Exam
32. What is the molar solubility of PbCl2 (Ksp = 1.6 × 10-6) ?
A.
B.
C.
D.
E.
1.3 × 10-3
8.9 × 10-4
9.3 × 10-3
7.4 × 10-3
6.3 × 10-4
33. E˚ = +0.620 for the following reaction. Calculate the equilibrium constant at 25˚C for the
reaction.
Cu (s) + 2Ag+ (aq)  2Ag (s) + Cu2+ (aq)
A.
B.
C.
D.
E.
3.0  1010
6.2  1022
3.0  1018
6.2  1014
9.4  1020
34. A first order chemical reaction is observed to have a rate constant of 35 / min. What is the
corresponding half-life for the reaction?
A.
B.
C.
D.
E.
18 min
20 min
3.2 sec
1.2 sec
0.83 sec
35. CO3-2, is readily classified as a
A.
B.
C.
D.
E.
Brønsted-Lowry acid
Brønsted-Lowry base
Lewis acid
Lewis base
non-acidic and non-basic compound
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Spring 2008 Final Exam
36. Given Ka values of 5.6 × 10-10 and 4.8 × 10-10 for NH4+ and HCN respectively, calculate the
equilibrium constant for the following reaction.
NH4+ + CNA.
B.
C.
D.
E.
NH3 + HCN
2.7 × 10-19
8.0 × 10-11
1.0 × 10-9
0.86
1.2
CHE 116
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Spring 2008 Final Exam