Question 1

Barbiturates are synthetic drugs used as sedatives and hypnotics. Barbital ( b = 3.07°C/m; boiling point of pure acetic acid = 117.9°C A)  117.0°C B)  117.7°C C)  118.1°C D)  118.8°C E)  >120°C" class="answers-bank-image d-inline" rel="preload" > = 184.2 g/mol)  is one of the simplest of these drugs. What is the boiling point of a solution prepared by dissolving 42.5 g of barbital in 825 g of acetic acid? Kb = 3.07°C/m; boiling point of pure acetic acid = 117.9°C

Accepted Answer

A)   117.0°C
B)   117.7°C
C)   118.1°C
D)   118.8°C
E)   >120°CF) B) and E)
G) None of the above

Question 2

Calculate the freezing point of a solution made by dissolving 3.50 g of potassium chloride ( f = 1.86°C/m. A)  -1.7°C B)  -0.9°C C)  0.0°C D)  0.9°C E)  1.7°C" class="answers-bank-image d-inline" rel="preload" > = 74.55 g/mol)  in 100.0 g of water. Assume ideal behavior for the solution; Kf = 1.86°C/m.

Accepted Answer

A)   -1.7°C
B)   -0.9°C
C)   0.0°C
D)   0.9°C
E)   1.7°CF) B) and E)
G) A) and E)

Question 3

Children under the age of six with more than 0.10 ppm of lead in their blood can suffer a reduction in I.Q. or have behavior problems. What is the molality of a solution which contains 0.10 ppm of lead?

Accepted Answer

A)   4.8 × 10-10 m
B)   4.8 × 10-7 m
C)   4.8 × 10-4 m
D)   4.8 × 10-1 m
E)   none of the aboveF) B) and E)
G) A) and B)

Question 4

Predict the ideal van't Hoff factor (i) for each of the following solutes:
a. CaCl2
b. Fe2(SO4)3
c. NH4Cl

Accepted Answer

Question 5

A solution of sucrose (sugar)  in water is in equilibrium with solid sucrose. If more solid sucrose is now added, with stirring,

Accepted Answer

A)   the concentration of the solution will increase.
B)   the concentration of the solution will decrease.
C)   the concentration of the solution will remain the same.
D)   the volume of solution will increase.
E)   a supersaturated solution will be produced.F) B) and C)
G) C) and D)

Question 6

If the density of a solution is less than 1.0 g/mL, its molarity will be greater than its molality.

Accepted Answer

A) True 
 B)False

Question 7

Potassium fluoride is used for frosting glass. Calculate the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution.

Accepted Answer

A)   0.304 M
B)   0.349 M
C)   1.35 M
D)   3.29 M
E)   6.01 MF) C) and D)
G) B) and D)

Question 8

Potassium hydrogen phosphate is used in the preparation of non-dairy powdered creamers. Calculate the molarity of a solution prepared by dissolving 238 g of K2HPO4 in enough water to produce 275 mL of solution.

Accepted Answer

A)   0.732 M
B)   0.865 M
C)   2.66 M
D)   4.97 M
E)   none of the aboveF) C) and D)
G) A) and D)

Question 9

From the following list of aqueous solutions and water, select the one with the highest boiling point.

Accepted Answer

A)   1.0 m KNO3
B)   0.75 m NaCl
C)   0.75 m CuCl2
D)   2.0 m C12H22O11 (sucrose) 
E)   pure waterF) A) and B)
G) A) and C)

Question 10

What volume of concentrated (14.7 M)  phosphoric acid is needed to prepare 25.0 L of 3.0 M H3PO4?

Accepted Answer

A)   0.20 L
B)   0.57 L
C)   1.8 L
D)   3.6 L
E)   5.1 LF) B) and D)
G) None of the above

Question 11

A 7.112 M solution of sulfuric acid (H2SO4) in water has a density of 1.395 g/mL. What is its molality?

Accepted Answer

Question 12

Which of the following aqueous solutions should demonstrate the most non-ideal behavior?

Accepted Answer

A)   0.1 M NaI
B)   0.2 M CuSO4
C)   0.5 M KBr
D)   2.0 M CuCl2
E)   2.0 M CsClF) A) and B)
G) A) and D)

Question 13

Which of the following pairs of ions is arranged so that the ion with the smaller charge density is listed first?

Accepted Answer

A)   K+, Rb+
B)   Cl-, K+
C)   Cl-, Br-
D)   Ca2+, Ba2+
E)   None of the above pairs are arranged in this way.F) A) and B)
G) B) and E)

Question 14

Isoamyl salicylate (  = 208.25 g/mol)  has a pleasant aroma and is used in perfumes and soaps. Which of the following combinations gives a 0.75 m solution of isoamyl salicylate in ethyl alcohol (d = 0.7893 g/mL) ?

Accepted Answer

A)   117.2 g isoamyl salicylate in 950.0 mL of ethyl alcohol
B)   117.2 g isoamyl salicylate in 750.0 mL of ethyl alcohol
C)   117.2 g isoamyl salicylate in 750.0 mL of solution
D)   117.2 g isoamyl salicylate in 592.0 g of ethyl alcohol
E)   none of the aboveF) A) and E)
G) D) and E)

Question 15

A 0.137 m solution of sodium ferrocyanide (Na4Fe(CN)6.10H2O) in water has a freezing point depression of 0.755°C. Calculate the van't Hoff factor (i) under these conditions. (Kf = 1.86°C/m)

Accepted Answer

Question 16

A solution of ethanol (C2H6O)  in water is sometimes used as a disinfectant. 1.00 L of this solution contains 553 g of ethanol and 335 g of water. What is the mole fraction of ethanol in this solution?

Accepted Answer

A)   0.377
B)   0.392
C)   0.553
D)   0.608
E)   0.623F) A) and D)
G) C) and D)

Question 17

The mole fraction of potassium nitrate in an aqueous solution is 0.0194. The solution's density is 1.0627 g/mL. Calculate the molarity of the solution.

Accepted Answer

A)   0.0194 M
B)   0.981 M
C)   1.05 M
D)   1.96 M
E)   19.4 MF) A) and B)
G) C) and E)

Question 18

Octane and nonane are liquids which are components of gasoline. Their vapor pressures at 25°C are 13.9 torr and 4.7 torr, respectively. What is the vapor pressure of a mixture consisting of 1 mole of each of these compounds?

Accepted Answer

The answer of Octane and nonane are liquids which are...

Question 19

Aqueous ammonia is commercially available in a solution that is 28% (w/w)  ammonia. What is the mole fraction of ammonia in such a solution?

Accepted Answer

A)   0.017
B)   0.023
C)   0.012
D)   0.24
E)   0.29F) B) and D)
G) None of the above

Question 20

Soda drinks bubble when the bottle is opened because

Accepted Answer

A)   the temperature of the soda increases.
B)   exposure to atmospheric pressure squeezes the carbon dioxide from solution.
C)   the partial pressure of carbon dioxide above the solution is reduced.
D)   atmospheric nitrogen molecules displace carbon dioxide molecules.
E)   the Henry's law constant changes due to the change in pressure.F) All of the above
G) A) and B)

Exam 13: The Properties of Mixtures: Solutions and Colloids

Which of the following aqueous solutions should demonstrate the most non-ideal behavior?

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If the density of a solution is less than 1.0 g/mL, its molarity will be greater than its molality.

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A 0.137 m solution of sodium ferrocyanide (Na4Fe(CN)6.10H2O) in water has a freezing point depression of 0.755°C. Calculate the van't Hoff factor (i) under these conditions. (Kf = 1.86°C/m)

Correct AnswerverifiedShow Answer

Soda drinks bubble when the bottle is opened because

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Predict the ideal van't Hoff factor (i) for each of the following solutes: a. CaCl2 b. Fe2(SO4)3 c. NH4Cl

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Which of the following pairs of ions is arranged so that the ion with the smaller charge density is listed first?

Correct AnswerverifiedShow Answer

Aqueous ammonia is commercially available in a solution that is 28% (w/w) ammonia. What is the mole fraction of ammonia in such a solution?

Correct AnswerverifiedShow Answer

From the following list of aqueous solutions and water, select the one with the highest boiling point.

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Potassium fluoride is used for frosting glass. Calculate the molarity of a solution prepared by dissolving 78.6 g of KF in enough water to produce 225 mL of solution.

Correct AnswerverifiedShow Answer

Octane and nonane are liquids which are components of gasoline. Their vapor pressures at 25°C are 13.9 torr and 4.7 torr, respectively. What is the vapor pressure of a mixture consisting of 1 mole of each of these compounds?

Correct AnswerverifiedShow Answer

A solution of ethanol (C2H6O) in water is sometimes used as a disinfectant. 1.00 L of this solution contains 553 g of ethanol and 335 g of water. What is the mole fraction of ethanol in this solution?

Correct AnswerverifiedShow Answer

Isoamyl salicylate ( = 208.25 g/mol) has a pleasant aroma and is used in perfumes and soaps. Which of the following combinations gives a 0.75 m solution of isoamyl salicylate in ethyl alcohol (d = 0.7893 g/mL) ?

Correct AnswerverifiedShow Answer

A solution of sucrose (sugar) in water is in equilibrium with solid sucrose. If more solid sucrose is now added, with stirring,

Correct AnswerverifiedShow Answer

Potassium hydrogen phosphate is used in the preparation of non-dairy powdered creamers. Calculate the molarity of a solution prepared by dissolving 238 g of K2HPO4 in enough water to produce 275 mL of solution.

Correct AnswerverifiedShow Answer

Children under the age of six with more than 0.10 ppm of lead in their blood can suffer a reduction in I.Q. or have behavior problems. What is the molality of a solution which contains 0.10 ppm of lead?

Correct AnswerverifiedShow Answer

Barbiturates are synthetic drugs used as sedatives and hypnotics. Barbital ( = 184.2 g/mol) is one of the simplest of these drugs. What is the boiling point of a solution prepared by dissolving 42.5 g of barbital in 825 g of acetic acid? Kb = 3.07°C/m; boiling point of pure acetic acid = 117.9°C

Correct AnswerverifiedShow Answer

A 7.112 M solution of sulfuric acid (H2SO4) in water has a density of 1.395 g/mL. What is its molality?

Correct AnswerverifiedShow Answer

The mole fraction of potassium nitrate in an aqueous solution is 0.0194. The solution's density is 1.0627 g/mL. Calculate the molarity of the solution.

Correct AnswerverifiedShow Answer

What volume of concentrated (14.7 M) phosphoric acid is needed to prepare 25.0 L of 3.0 M H3PO4?

Correct AnswerverifiedShow Answer

Calculate the freezing point of a solution made by dissolving 3.50 g of potassium chloride ( = 74.55 g/mol) in 100.0 g of water. Assume ideal behavior for the solution; Kf = 1.86°C/m.

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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A 0.137 m solution of sodium ferrocyanide (Na₄Fe(CN)₆.10H₂O) in water has a freezing point depression of 0.755°C. Calculate the van't Hoff factor (i) under these conditions. (K_f= 1.86°C/m)

Correct Answer
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Correct Answer
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Predict the ideal van't Hoff factor (i) for each of the following solutes: a. CaCl₂ b. Fe₂(SO₄)₃ c. NH₄Cl

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Correct Answer
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Correct Answer
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Correct Answer
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A solution of ethanol (C₂H₆O) in water is sometimes used as a disinfectant. 1.00 L of this solution contains 553 g of ethanol and 335 g of water. What is the mole fraction of ethanol in this solution?

Correct Answer
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Correct Answer
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Correct Answer
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Potassium hydrogen phosphate is used in the preparation of non-dairy powdered creamers. Calculate the molarity of a solution prepared by dissolving 238 g of K₂HPO₄in enough water to produce 275 mL of solution.

Correct Answer
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Correct Answer
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Barbiturates are synthetic drugs used as sedatives and hypnotics. Barbital ( = 184.2 g/mol) is one of the simplest of these drugs. What is the boiling point of a solution prepared by dissolving 42.5 g of barbital in 825 g of acetic acid? K_b = 3.07°C/m; boiling point of pure acetic acid = 117.9°C

Correct Answer
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A 7.112 M solution of sulfuric acid (H₂SO₄) in water has a density of 1.395 g/mL. What is its molality?

Correct Answer
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Correct Answer
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What volume of concentrated (14.7 M) phosphoric acid is needed to prepare 25.0 L of 3.0 M H₃PO₄?

Correct Answer
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Calculate the freezing point of a solution made by dissolving 3.50 g of potassium chloride ( = 74.55 g/mol) in 100.0 g of water. Assume ideal behavior for the solution; K_f = 1.86°C/m.

Correct Answer
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