Same problems that were on the Smart Board:
4. The equilibrium expression for Kc for the system
CaSO3(s) CaO(s) + SO2(g)
is
[A] .
[B] [CaO][SO2] .
[C] [SO2].
[D] .
[E] .
5. For which of the following values of the equilibrium constant does the reaction mixture contain essentially products?
[A] 107
[B] 101
[C] 100
[D] 10–1
[E] 10–7
6. Carbon disulfide and chlorine react according to the following equation:
CS2(g) + 3Cl2(g) S2Cl2(g) + CCl4(g)
When 1.00 mol of CS2 and 4.00 mol of Cl2 are placed in a 2.00-L container and allowed to come to equilibrium, the mixture is found to contain 0.500 mol of CCl4. How many moles of Cl2 are present at equilibrium?
[A] 0.75
[B] 1.50
[C] 2.50
[D] 2.75
[E] 3.00
8. In an experiment, 0.400 mol H2 and 0.400 mol I2 are mixed in a 1.00-L container, and the reaction forms HI. If Kc = 49. for this reaction, what is the equilibrium concentration of HI?
I2(g) + H2(g) 2HI(g)
[A] 0.090 M
[B] 0.18 M
[C] 0.31 M
[D] 0.62 M
[E] 0.83 M
9. Consider the reaction
S2Cl2(l) + CCl4(l) CS2(g) + 3Cl2(g) DH° = 84.3 kJ
If the above reactants and products are contained in a closed vessel and the reaction system is at equilibrium, the number of moles of CS2 can be increased by
[A] adding some S2Cl2 to the system.
[B] adding some Cl2 to the system.
[C] increasing the size of the reaction vessel.
[D] decreasing the temperature of the reaction system.
[E] adding some CCl4 to the system.
10. Which of the following equilibria would be affected by pressure changes at constant temperature?
1. CO(g) + 1/2 O2(g) CO2(g)
2. CaCO3(s) CaO(s) + CO2(g)
3. CO2(g) + H2(g) CO(g) + H2O(g)
[A] 1 only
B] 2 only
[C] 3 only
D] 1 and 2 only
[E] 1, 2, and 3
13. At 25°C, the reaction
2ICl(g) I2(g) + Cl2(g) DH = 27 kJ
has a K value of 6.2 ´ 10–6. Which of the following would be true if the temperature were increased to 100°C?
1. The value of K would be larger.
2. The concentration of ICl(g) would be increased.
3. The partial pressure of I2 would increase.
[A] 1 only
[B] 2 only
[C] 3 only
[D] 1 and 2 only
[E] 2 and 3 only
16. The decomposition of carbon dioxide proceeds as follows:
2CO2(g) 2CO(g) + O2(g) DH = 559 kJ
Which of the following will cause an INCREASE in the equilibrium concentration of CO?
[A] Increasing the pressure of the system at constant temperature
[B] Adding more O2 to the system
[C] Removing CO2 from the system
[D] Increasing the temperature of the system
[E] Adding a catalyst
17. For a specific reaction, which of the following statements can be made about the equilibrium constant?
[A] It always remains the same.
[B] It increases when the concentration of one of the products is increased.
[C] It changes with changes in the temperature.
[D] It increases when the concentration of one of the reactants is increased.
[E] It can be changed by the addition of a catalyst.
20. Carbon monoxide is toxic because it can successfully compete with oxygen for hemoglobin (Hb) sites according to the following equilibrium
Hb(O2)4 + 4CO Hb(CO)4 + 4O2
From Le Chatelier’s Principle, how is CO poisoning reversed?
[A] by increasing the O2 pressure
B] by increasing the CO pressure
[C] by increasing the CO2 pressure
[D] by decreasing the amount of Hb
[E] by increasing the amount of Hb
27. The hydronium-ion concentration of a 0.010 molar hypochlorous acid solution, HOCl, is 5.48 ´ 10–6 M. What is the pH of the solution?
[A] 2.00
B] 5.26
[C] 5.48
[D] 6.00
[E] 6.74
28. Which of the following solutions would have the highest osmotic pressure?
[A] 0.15 M NaCl, sodium chloride
[B] 0.15 M CaCl2, calcium chloride
[C] 0.20 M CH3COOH, acetic acid
[D] 0.20 M C6H12O6, glucose
[E] 0.20 M C12H22O11, sucrose
29. If a 20.0-g sample of a nonelectrolyte is dissolved in 100 g of water, the resulting solution will freeze at –0.93°C (the freezing-point constant is 1.86°C/m). On the basis of these data, we can conclude that the nonelectrolyte has a molecular weight of
A] 10 g/mol.
[B] 50 g/mol.
[C] 100 g/mol.
[D] 200 g/mol.
E] 400 g/mol.
30. Which of the following solutes in aqueous solution would be expected to exhibit the SMALLEST freezing-point lowering (assuming ideal behavior)?
[A] 0.1 m NaCl
[B] 0.2 m CH3COOH
[C] 0.1 m MgCl2
[D] 0.05 m Al2(SO4)3
[E] 0.25 m NH3
31. For which of the following aqueous solutions would one expect to have the largest van’tHoff factor?
[A] 0.100 m C6H12O6 (glucose)
[B] 0.100 m NaCl
[C] 0.010 m NaCl
D] 0.100 m K2SO4
[E] 0.010 m K2SO4
36. In which of the following processes would one expect DS to have the value closest to zero?
[A] H2(g) + I2(s) 2HI(g)
[B] C2H4(g) + Br2(l) C2H4Br2(l)
[C] N2(g) + O2(g) 2NO(g)
[D] 2NO(g) + O2(g) 2NO2(g)
[E] CH3C(O)H(g) + O2(g) 2CO2(g) + 2H2O(g)
40. Calculate DG° for the reaction
Cu(s) + H2O(g) CuO(s) + H2(g)
at 500 K.
[A] +110.6 kJ
[B] –86.6 kJ
[C] +23.9 kJ
[D] –62.6 kJ
[E] +301 kJ
41. The best criterion for the spontaneity of a chemical reaction is the sign of
[A] DH.
[B] DH°.
[C] TDS.
[D] DG.
[E] DG°.
42. For the following process
Br2(l) 2Br(g)
[A] DH is + and DS is + for the reaction.
[B] DH is – and DS is – for the reaction.
[C] DH is + and DS is – for the reaction.
[D] DH is – and DS is + for the reaction.
[E] DG is + for all temperatures.
45. A reaction must be spontaneous at all temperatures when
[A] DG is negative.
[B] DH is positive and DS is positive.
[C] DH is positive and DS is negative.
[D] DH is negative and DS is negative.
[E] DH is negative and DS is positive.
46. When ammonium nitrate dissolves in water, the solution becomes cold. We can conclude the following:
[A] DH° is positive and DS° is positive.
[B] DH° is positive and DS° is negative.
[C] DH° is negative and DS° is negative.
[D] DH° is negative and DS° is positive.
[E] DH° is positive and DS° is zero.
49. Neon atoms do not combine to form Ne2 molecules, yet neon atoms can be liquified through the following intermolecular forces:
[A] dipole–dipole
[B] ion–dipole
[C] dipole–induced dipole
[D] dispersion
[E] nonmetal–nonmetal
50. Which compound should have the lowest heat of vaporization?
[A] C5H12
[B] C6H14
[C] C7H16
[D] C8H18
[E] C8H16
55. What is the molality of a solution that contains 73.5 g of 1,4-dichlorobenzene, C6H4Cl2, in 500 mL of carbon tetrachloride? (The density of CCl4 is 1.60g/mL.)
[A] 0.250 m
[B] 0.500 m
[C] 0.625 m
[D] 1.00 m
[E] 1.30 m
56. Which of the following has the LOWEST vapor pressure at room temperature?
[A] ethylene glycol, b.p. = 198°C
[B] ethanol, b.p. = 78°C
[C] water, b.p. = 100°C
[D] benzene, b.p. = 80°C
[E] carbon disulfide, b.p. = 46°C
57. Which of the following solutes dissolved in 1.0 kg of water would be expected to cause the water to freeze at the LOWEST temperature?
[A] 0.0015 mole of sucrose, C12H22O11
[B] 0.0030 mole of ethanol, C2H5OH
[C] 0.0030 mole of methanol, CH3OH
[D] 0.0015 mole of H2SO4
[E] 0.0015 mole of H2SO3
60. Which of the following solutes dissolved in 1000 g of water would provide the greatest number of particles?
[A] 0.030 mole urea, CO(NH2)2
[B] 0.030 mole acetic acid, CH3COOH
[C] 0.030 mole ammonium nitrate, NH4NO3
[D] 0.030 mole calcium sulfate, CaSO4
[E] 0.030 mole barium chloride, BaCl2
61. Which of the following solutes dissolved in 1000 g of water would provide a solution with the LOWEST freezing point?
[A] 0.030 mole urea, CO(NH2)2
[B] 0.030 mole acetic acid, CH3COOH
[C] 0.030 mole ammonium nitrate, NH4NO3
[D] 0.030 mole calcium sulfate, CaSO4
[E] 0.030 mole barium chloride, BaCl2
62. Which of the following aqueous solutions would be expected to be the best conductor of an electric current at room temperature?
[A] 0.10 M CH3COOH
[B] 0.10 M NaCl
[C] 0.10 M HCl
[D] 0.10 M H2SO4
[E] 0.10 M H3PO4
Reference: [14.1.3]
[4] [C]
Reference: [14.1.4]
[5] [A]
Reference: [14.1.7]
[6] [C]
Reference: [14.1.27]
[8] [D]
Reference: [14.1.41]
[9] [C]
Reference: [14.1.43]
[10] [D]
Reference: [14.1.48]
[13] [D]
Reference: [14.1.52]
[16] [D]
Reference: [14.1.53]
[17] [C]
Reference: [14.2.73]
[20] [A]
Reference: [15.1.59]
[27] [B]
Reference: [12.1.99]
[28] [B]
Reference: [12.1.96]
[29] [E]
Reference: [12.1.95]
[30] [A]
Reference: [12.1.91]
[31] [E]
Reference: [18.1.25]
[36] [C]
Reference: [18.1.42]
[40] [A]
Reference: [18.1.44]
[41] [D]
Reference: [18.1.58]
[42] [A]
Reference: [18.1.64]
[45] [E]
Reference: [18.1.65]
[46] [A]
Reference: [11.1.5]
[49] [D]
Reference: [11.1.8]
[50] [A]
Reference: [12.1.38]
[55] [C]
Reference: [12.1.51]
[56] [E]
Reference: [12.1.64]
[57] [D]
Reference: [12.1.68]
[60] [E]
Reference: [12.1.69]
[61] [E]
Reference: [12.1.70]
[62] [C]