Version B

SECTION: (circle one): A01 MR (Dr. Lipson)
A02 (Dr. Briggs)
A03 MWR (Dr. Brolo)
NAME _______________________________________ Student No. V0______________________
(Please print clearly.)
Midterm Test 2
March 15, 2013
5-6 pm (60 minutes)
Answer all questions on the bubble sheet provided.
PRINT and shade in only your last name, first name, and the last 7 digits of your
student ID number on the bubble sheet. i.e. Omit the leading V0.
Do NOT include any information about the course, section or date on the bubble sheet.
Hand in only the bubble sheet at the end of the test period (60 minutes).
A DATA sheet is included, unstapled, inside the cover page of this test.
This test has 6 pages (not including the DATA sheet). Count the pages before you begin.
The basic Sharp EL510 calculator is the only one approved for use in Chemistry 102.
Chemistry 102, Mid-Term Test 2
Version B March 2013
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Select the BEST response for each question below. [Total marks = 26]
This test consists entirely of multiple choice questions and is worth 50 marks. There are two marks per
question except Question 1. The answers for the 26 questions in this part must be coded on the optical
sense form (bubble sheet) using a SOFT PENCIL.
Select the BEST response for each question below.
1. This is exam Version B. Mark “B” as the answer to question 1 on the optical sense form.
2. For which one of the following reactions is ΔH°rxn equal to the enthalpy of formation (i.e. heat of
formation) of the product?
A) N2 (g) + 3H2 (g) → 2NH3 (g)
B) P (g) + 4H (g) + Br (g) → PH4Br (l)
C) 6C (s) + 6H (g) → C6H6 (l)
D) (1/2) N2 (g) + O2 (g) → NO2 (g)
E) 12C (g) + 11H2 (g) + 11O (g) → C6H22O11 (g)
3. The temperature of a 12.58 g sample of calcium carbonate [CaCO3 (s)] increases from 23.6 °C to 38.2
°C. If the specific heat of calcium carbonate is 0.82 J/g-K, how many joules of heat are absorbed?
A) 151
B) 5.0
C) 7.5
D) 410
E) 0.82
Consider the following two reactions:
A → 2B
ΔH°rxn = 456.7 kJ/mol
ΔH°rxn = -22.1kJ/mol
Determine the enthalpy change for the process:
2B → C
A) 478.8 kJ/mol
B) -478.8 kJ/mol
C) 434.6 kJ/mol
D) -434.6 kJ/mol
E) More information is needed to solve the problem.
Chemistry 102, Mid-Term Test 2
Version B March 2013
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5. The specific heat of liquid bromine is 0.226 J g−1K−1. How much heat (J) is required to raise the
temperature of 10.0 mL of bromine from 25.00 °C to 27.30 °C? The density of liquid bromine: 3.12 g/mL.
A) 5.20
B) 32.4
C) 300
D) 16.2
E) 10.4
6. ΔH for the reaction
IF5 (g) → IF3 (g) + F2 (g)
is __________ kJ, given the data below.
IF (g) + F2 (g) → IF3 (g)ΔH = -390 kJ
IF (g) + 2 F2 (g) → IF5 (g) ΔH = -745 kJ
A) +355
B) -1135
C) +1135
D) +35
E) -35
Calculate ΔH° (in kJ) for this reaction: C6H4(OH)2(l) + H2O2(g) → C6H4O2(l) + 2 H2O(l)
Use the information on the Data Sheet and
C6H4(OH)2(l) → C6H4O2(l) + H2(g)
+177.4 kJ
A. 71.7
B. -384.2
D. +27.7
E. -170.1
C. -258.2
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Version B March 2013
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8. The ΔHsoln for the process when solid sodium hydroxide (NaOH) dissolves in water is 44.4 kJ/mol. When
a 10.0 g sample of NaOH dissolves in 250.0 g of water in a coffee-cup calorimeter, the temperature increases
from 23.0 °C to __________°C. Assume that the solution has the same specific heat as liquid water, i.e. 4.18
J g−1K−1.
A) 35.2
B) 24.0
C) 33.2
D) 33.6
E) 40.2
Given the data in the table below, ΔH°rxn for the reaction below is __________ kJ.
4NH3 (g) + 5 O2 (g) → 4NO (g) + 6 H2O (l)
A) -1172
B) -150
C) -1540
D) -1892
E) The ΔHf ° of O2 (g) is needed for the calculation.
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Version B March 2013
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10. The average fuel value of sugars is 17 kJ/g. A 2.0 L pitcher of sweetened Kool-Aid contains 400 g of
sugar. What is the fuel value (in kJ) of a 500 mL serving of Kool-Aid? (Assume that the sugar is the only
fuel source.)
A) 4.2 × 104
B) 1.7 × 106
C) 1.7 × 103
D) 1.7 × 102
E) 17
11. How high a liquid will rise up a narrow tube as a result of capillary action depends on __________.
A) the magnitudes of cohesive forces in the liquid and adhesive forces between the liquid and the tube, and
B) gravity alone
C) only the magnitude of adhesive forces between the liquid and the tube
D) the viscosity of the liquid
E) only the magnitude of cohesive forces in the liquid
12. Some things take longer to cook at high altitudes than at low altitudes because __________.
A) water boils at a lower temperature at high altitude than at low altitude
B) water boils at a highertemperature at high altitude than at low altitude
C) heat isn't conducted as well in low density air
D) natural gas flames don't burn as hot at high altitudes
E) there is a higher moisture content in the air at high altitude
Chemistry 102, Mid-Term Test 2
Version B March 2013
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13. Which of the following statements is/are TRUE about the substance that has the phase diagram shown
(i) The three phases are at equilibrium at the point z.
(ii) At temperatures higher than 18°C the gas cannot liquefy by compression.
(iii) Increasing the pressure on the solid at 12 °C will cause the solid to liquefy.
A) (i) and (ii) and (iii)
B) (i) only
C) (iii) only
D) (ii) only
E) (i) and (iii)
14. The normal melting point of the substance with the phase diagram shown above is __________°C.
A) 5
B) 25
C) 35
D) 45
E) 15
15. 4) Calculate the enthalpy change (in kJ) associated with the conversion of 25.0 grams of ice at -4.00°C to
liquid water at 76.0°C. The specific heats of ice and liquid water are 2.09 J/gK, 4.18 J/gK, respectively.
For H2O, ΔHfus = 6.01 kJ/mol.
A) 8.16
B) 14.0
C) 16,500
D) 16.5
E) 18.0
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Version B March 2013
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16. Consider a liquid in dynamic equilibrium with its vapor in a closed container at a given temperature.
Indicate ALL of the following conditions that are TRUE:
There is no transfer of molecules between liquid and vapor
The vapor pressure has a unique value
The opposing processes, (liquid to vapor) and (vapor to liquid), proceed at equal rates
The concentration of vapor will change as time elapses.
B. I and II
D. III and IV
E. I
C. II and III
17. The equilibrium constant for reaction 1below is K. The equilibrium constant for reaction 2 is
(1) SO2 (g) + (1/2) O2 (g)
(2) 2SO3 (g)
SO3 (g)
2SO2 (g) + O2 (g)
A) K2
B) 2K
C) 1/K2
D) 1/2K
E) -K2
18. Which of the following expressions is the correct equilibrium-constant expression for the reaction
HF (aq) + H2O (l)
A) [HF][H2O] / [H3O+][F-]
B) 1 / [HF]
C) [H3O+][F-] / [HF][H2O]
D) [H3O+][F-] / [HF]
E) [F-] / [HF]
H3O+ (aq) + F- (aq)
Chemistry 102, Mid-Term Test 2
Version B March 2013
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19. Equal quantities of hydrogen and gaseous iodine at 700 K (427 °C) are placed in a reaction vessel and
allowed to reach equilibrium according to the following equation:
H2(g) + I2(g)
2 HI(g)
If the following equilibrium concentrations are measured:[H2] = [I2] = 0.021 mol L-1 and
[HI] = 0.158 mol L-1, what is the equilibrium constant for this reaction at 700K?
A. 57
B. 1.2
C. 360
D. 0.018
E. 7.5
20. Of the following equilibria, only __________ will shift to the left in response to a decrease in volume.
A) H2 (g) + Cl2 (g)
2 HCl (g)
B) 2 SO3 (g)
2 SO2 (g) + O2 (g)
C) N2 (g) + 3 H2 (g)
2 NH3 (g)
D) 4 Fe (s) + 3 O2 (g)
2 Fe2O3 (s)
E) 2HI (g)
H2 (g) + I2 (g)
21. Sulfuryl dichloride (SO2Cl2) can be prepared by the following two-step reaction sequence.
H2S(g) + 1.5 O2(g)  SO2(g) + H2O(g)
SO2(g) + Cl2(g)  SO2Cl2(g)
The reaction quotient (Qc) for the overall (sum) reaction for producing sulfuryl dichloride is:
SO 2 Cl 2
SO 2 Cl 2
SO 2 H 2 O
H 2 O SO 2 Cl 2
H 2 O SO 2 Cl 2
SO 2 H 2 O
Cl 2 H 2S O 2
H 2S O 2
H 2S O 2 1.5
Cl 2 H 2S O 2 1.5
22. At elevated temperatures, molecular hydrogen and molecular bromine react to partially form hydrogen
H2 (g) + Br2 (g)
2HBr (g)
A mixture of 0.682 mol of H2 and 0.440 mol of Br2 is combined in a reaction vessel with a volume of 2.00
L. At equilibrium at 700 K, there are 0.556 mol of H2 present. At equilibrium, there are __________ mol of
Br2 present in the reaction vessel.
A) 0.000
B) 0.440
C) 0.556
D) 0.314
E) 0.126
Chemistry 102, Mid-Term Test 2
Version B March 2013
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23. ΔS is positive for the reaction __________.
A) 2NO (g) + O2 (g) → 2NO2 (g)
B) C3H8 (g) + 5 O2 (g) → 3CO2 (g) + 4 H2O (g)
C) 2N2 (g) + 3H2 (g) → 2 NH3 (g)
D) Mg (s) + Cl2 (g) → MgCl2 (s)
E) C2H4 (g) + H2 (g) → C2H6 (g)
24. Which of the following pairs has the member with the greatest molar entropy listed first?
A. CH3OH(l); C2H5OH(l)
B.KClO3(s); KClO3(aq)
C. HNO3(l); HNO3(aq)
D. K(s); Na(s)
E. CuSO4(s); CuSO4•5H2O(s)
25. Which statement is CORRECT for a reaction that has Kc = 2.43 × 10–12?
A. Increasing the temperature will not change the value of Kc.
B. There are significant concentrations of reactants and products at equilibrium.
C. The reaction proceeds nearly all the way toward completion.
D. The reaction proceeds hardly at all toward completion.
E. The reaction is endothermic.
26. An important reaction that occurs in the atmosphere is NO2(g)  NO(g) + O(g), which is brought about
by sunlight. Given the reactions listed below, how much energy would have to be supplied by the sun
for this reaction to occur?
O2(g) → 2 O(g)
ΔHº = +498.4 kJ
NO(g) + O3(g)  NO2(g) + O2(g)
3O2(g)  2O3(g)
A. 413 kJ
B. 306.5 kJ
ΔHº = -200 kJ
ΔHº= +285.4 kJ/mol
C. 613 kJ
D. 583.8 kJ
E. 383.8 kJ
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