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]