Deck 13: Properties of Solutions

Question 1

Which of the following liquids will have the lowest freezing point?

A) pure H₂O
B) aqueous CoI₂ (0.030 m)
C) aqueous FeI₃ (0.030 m)
D) aqueous glucose (0.050 m)
E) aqueous NaI (0.030 m)

Answer 1

aqueous FeI₃ (0.030 m)

Question 2

A solution is prepared by dissolving calcium chloride in water and diluting to 500.0 mL. If this solution contains 44 ppm chloride ions, the concentration of calcium ions is ppm.

A) 11
B) 44
C) 88
D) 500
E) 22

Answer 2

22

Question 3

A supersaturated solution _ _.

A) is one with a higher concentration than the solubility
B) exists only in theory and cannot actually be prepared
C) is one that has been heated
D) must be in contact with undissolved solid
E) is one with more than one solute

Answer 3

is one with a higher concentration than the solubility

Question 4

The dissolution of water in octane (C₈H₁₈) is prevented by _ _.

A) hydrogen bonding between water molecules
B) repulsion between like- charged water and octane molecules
C) dipole- dipole attraction between octane molecules
D) London dispersion forces between octane molecules
E) ion- dipole attraction between water and octane molecules

Question 5

When solutions of strong electrolytes in water are formed, the ions are surrounded by water molecules. These interactions are best described as a case of _.

A) hydration
B) crystallization
C) supersaturation
D) dehydration
E) solvation

Question 6

The dissolution of gases in water is virtually always exothermic because _.

A) neither of the two endothermic steps in the solution- formation process is necessary
B) one of the two endothermic steps (separation of solute particles) in the solution- formation process is unnecessary
C) gases react exothermically with water
D) the exothermic step in the solution- formation process is unnecessary
E) all three steps in the solution- formation process are exothermic

Question 7

Which of the following is not a colloid?

A) whipped cream
B) smoke
C) air
D) homogenized milk
E) fog

Question 8

A solution is prepared by adding 30.00 g of lactose (milk sugar) to 110.0 g of water at 55 °C. The partial pressure of water above the solution is torr. The vapor pressure of pure water at 55 °C is 118 torr. The MW of lactose is 342.3 g/mol.

A) 169.4
B) 1.670
C) 92.7
D) 94.1
E) 116.3

Question 9

An unsaturated solution is one that _.

A) contains the maximum concentration of solute possible, and is in equilibrium with undissolved solute
B) has a concentration lower than the solubility
C) contains no solute
D) has no double bonds
E) contains more dissolved solute than the solubility allows

Question 10

Ammonium nitrate (NH₄NO₃) dissolves readily in water even though the dissolution is endothermic by 26.4 kJ/mol. The solution process is spontaneous because _.

A) of the increase in disorder upon dissolution of this strong electrolyte
B) the vapor pressure of the water decreases upon addition of the solute
C) of the increase in enthalpy upon dissolution of this strong electrolyte
D) of the decrease in enthalpy upon addition of the solute
E) osmotic properties predict this behavior

Question 11

A solution contains 28% phosphoric acid by mass. This means that .

A) 1 mL of this solution contains 28 g of phosphoric acid
B) the density of this solution is 2.8 g/mL
C) 1 L of this solution has a mass of 28 g
D) 100 g of this solution contains 28 g of phosphoric acid
E) 1 L of this solution contains 28 mL of phosphoric acid

Question 12

Which of the following cannot be a colloid?

A) a foam
B) an aerosol
C) an emulsion
D) a homogenous mixture
E) All of the above are colloids.

Question 13

Calculate the freezing point of a solution containing 40.0 grams of KCl and 4400.0 grams of water. The molal- freezing- point- depression constant (K_f) for water is 1.86 ° C/m.

A) +0.45 ^oC
B) - 0.45 ^oC
C) - 0.23 ^oC
D) 1.23 ^oC
E) +0.23 ^oC

Question 14

When argon is placed in a container of neon, the argon spontaneously disperses throughout the neon because .

A) of solvent- solute interactions
B) the dispersion of argon atoms produces an increase in disorder
C) of hydrogen bonding
D) of the large attractive forces between argon and neon atoms
E) a decrease in energy occurs when the two mix

Question 15

A saturated solution .

A) contains as much solvent as it can hold
B) cannot be attained
C) contains dissolved solute in equilibrium with undissolved solid
D) will rapidly precipitate if a seed crystal is added
E) contains no double bonds

Question 16

The phrase "like dissolves like" refers to the fact that _.

A) gases can only dissolve other gases
B) condensed phases can only dissolve other condensed phases
C) polar solvents dissolve polar solutes and nonpolar solvents dissolve nonpolar solutes
D) polar solvents dissolve nonpolar solutes and vice versa
E) solvents can only dissolve solutes of similar molar mass

Question 17

In a saturated solution of a salt in water, .

A) seed crystal addition may cause massive crystallization
B) the rate of crystallization > the rate of dissolution
C) addition of more water causes massive crystallization
D) the rate of dissolution > the rate of crystallization
E) the rate of crystallization = the rate of dissolution

Question 18

A 0.100 m solution of which one of the following solutes will have the lowest vapor pressure?

A) Ca(ClO₄)₂
B) Al(ClO₄)₃
C) KClO₄
D) sucrose
E) NaCl

Question 19

The Henry's law constant for helium gas in water at 30 °C is 3.70 × 10^{- 4} M/atm. When the partial pressure of helium above a sample of water is 0.650 atm, the concentration of helium in the water is M

A) 1.76 × 10³
B) 2.41 × 10^{- 4}
C) 5.69 × 10^{- 4}
D) 3.70 × 10^{- 4}
E) 1.30

Question 20

Which one of the following is most soluble in hexane (C₆H₁₄)?

A) CH₃CH₂CH₂OH
B) CH₃OH
C) CH₃CH₂CH₂CH₂CH₂OH
D) CH₃CH₂CH₂CH₂OH
E) CH₃CH₂OH

Question 21

A solution is prepared by dissolving 16.2 g of benzene (C₆H₆) in 282 g of carbon tetrachloride (CCl₄). The concentration of benzene in this solution is molal. The molar masses of C₆H₆ and CCl₄ are 78.1 g/mol and 154 g/mol, respectively.

A) 0.102
B) 7.36 × 10^{- 4}
C) 5.43
D) 0.736
E) 0.0543

Question 22

At 20°C, a 2.32 M aqueous solution of ammonium chloride has a density of 1.0344 g/mL. What is the molality of ammonium chloride in the solution? The formula weight of NH₄Cl is 53.50 g/mol.

A) 0.0449
B) 2.55
C) 12.00
D) 0.446
E) 2.32

Question 23

A solution is prepared by dissolving 7.00 g of glycerin (C₃H₈O₃) in 201 g of ethanol (C₂H₅OH). The freezing point of the solution is °C. The freezing point of pure ethanol is - 114.6 °C at 1 atm. The molal- freezing- point- depression constant (K_f) for ethanol is 1.99 ° C/m. The molar masses of glycerin and of ethanol are 92.1 g/mol and 46.1 g/mol, respectively.

A) - 121.3
B) - 107.9
C) - 113.8
D) 0.752
E) - 115.4

Question 24

The concentration of chloride ion in a solution that contains 35.0 ppm chloride is % by mass.

A) 3.50 × 10¹
B) 3.50 × 10^{- 3}
C) 3.50 × 10^{- 6}
D) 3.50 × 10²
E) 3.50 × 10^{- 2}

Question 25

The most likely van't Hoff factor for an 0.01 m CaI₂ solution is .

A) 1.27
B) 1.00
C) 3.29
D) 2.69
E) 3.00

Question 26

Which one of the following substances is more likely to dissolve in CCl₄?

A) CBr₄
B) NaCl
C) HBr
D) HCl
E) CH₃CH₂OH

Question 27

At 20°C, a 3.54 M aqueous solution of ammonium chloride has a density of 1.0512 g/mL. What is the mass % of ammonium chloride in the solution? The formula weight of NH₄Cl is 53.50 g/mol.

A) 6.95
B) 4.10
C) 3.36
D) 18.00
E) 0.297

Question 28

Hydrophobic colloids .

A) can be stabilized by coagulation
B) can be stabilized by adsorption of ions
C) will separate into two phases if they are stabilized
D) are those that do not contain water
E) are those that contain water

Question 29

Molality is defined as the .

A) moles solute/kg solution
B) moles solute/Liters solution
C) moles solute/moles solvent
D) moles solute/kg solvent
E) none (dimensionless)

Question 30

The osmotic pressure of a solution formed by dissolving 25.0 mg of aspirin (C₉H₈O₄) in 0.250 L of water at 25 °C is atm.

A) 1.14 × 10^{- 3}
B) 0.0136
C) 1.38
D) 13.6
E) 2.45

Question 31

Of the concentration units below, only _ _ is temperature dependent.

A) mass %
B) ppb
C) ppm
D) molality
E) molarity

Question 32

Which of the following choices has the compounds correctly arranged in order of increasing solubility in water? (least soluble to most soluble

A) LiF < NaNO₃ < CHCl₃
B) CH₄ < NaNO₃ < CHCl₃
C) CH₃OH < CH₄ < LiF
D) CCl₄ < CHCl₃ < NaNO₃
E) CH₃OH < Cl₄ < CHCl₃

Question 33

Colligative properties of solutions include all of the following except .

A) the increase of reaction rates with increase in temperature
B) depression of vapor pressure upon addition of a solute to a solvent
C) depression of the freezing point of a solution upon addition of a solute to a solvent
D) an increase in the osmotic pressure of a solution upon the addition of more solute
E) elevation of the boiling point of a solution upon addition of a solute to a solvent

Question 34

If the partial pressure of oxygen in the air a diver breathes is too great, _.

A) respiratory tissue is damaged by oxidation
B) hyperventilation results
C) the urge to breathe is reduced and not enough CO₂ is removed from the body
D) the urge to breathe is increased and excessive CO₂ is removed from the body
E) No problems result from this situation.

Question 35

A solution contains 11% by mass of sodium chloride. This means that .

A) 100 mL of the solution contains 11 g of sodium chloride
B) the molality of the solution is 11
C) there are 11 g of sodium chloride in in 1.0 mL of this solution
D) the density of the solution is 11 g/mL
E) 100 g of the solution contains 11 g of sodium chloride

Question 36

Of the following, a 0.1 M aqueous solution of will have the lowest freezing point.

A) Al(NO₃)₃
B) NaCl
C) K₂CrO₄
D) Na₂SO₄
E) sucrose

Question 37

A solution is prepared by adding 1.43 mol of KCl to 889 g of water. The concentration of KCl is
Molal.

A) 622
B) 0.622
C) 1.61 × 10^{- 3}
D) 1.27 × 10³
E) 1.61

Question 38

The ideal value of i (van't Hoff factor) for (NH₄)₃PO₄.

A) 5
B) 1
C) 4
D) 3
E) 2

Question 39

Which one of the following substances is more likely to dissolve in benzene (C₆H₆)?

A) CCl₄
B) CH₃CH₂OH
C) HBr
D) NH₃
E) NaCl

Question 40

A 1.35 m aqueous solution of compound X had a boiling point of 101.4°C. Which one of the following could be compound X? The boiling point elevation constant for water is 0.52°C/m.

A) Na₃PO₄
B) CH₃CH₂OH
C) KCl
D) CaCl₂
E) C₆H₁₂O₆

Question 41

The Procter & Gamble Company product called olestra^TM is formed by combining a sugar molecule with .

A) alcohols
B) cholesterol
C) vitamin A
D) fatty acids
E) protein

Question 42

A solution contains 15 ppm of benzene. The density of the solution is 1.00 g/mL. This means that

A) there are 15 mg of benzene in 1.0 L of this solution
B) 100 g of the solution contains 15 g of benzene
C) 100 g of the solution contains 15 mg of benzene
D) the molarity of the solution is 15
E) the solution is 15% by mass of benzene

Question 43

Which produces the greatest number of ions when one mole dissolves in water?

A) NH₄NO₃
B) NH₄Cl
C) Na₂SO₄
D) NaCl
E) sucrose

Question 44

Formation of solutions where the process is endothermic can be spontaneous provided that
)

A) they are accompanied by an increase in order
B) the solvent is a gas and the solute is a solid
C) they are accompanied by an increase in disorder
D) the solvent is water and the solute is a gas
E) they are accompanied by another process that is exothermic

Question 45

Hydration is a specific example of the phenomenon known generally as .

A) condensation
B) disordering
C) dilution
D) salutation
E) solvation

Question 46

The principal reason for the extremely low solubility of NaCl in benzene (C₆H₆) is the _ .

A) strong solvent- solvent interactions
B) increased disorder due to mixing of solute and solvent
C) hydrogen bonding in C₆H₆
D) strength of the covalent bond in NaCl
E) weak solvation of Na⁺ and Cl^- by C₆H₆

Question 47

A solution with a concentration higher than the solubility is _.

A) is unsaturated
B) is supercritical
C) is saturated
D) is supersaturated
E) is not possible

Question 48

The process of a substance sticking to the surface of another is called

A) coagulation
B) adsorption
C) absorption
D) diffusion
E) effusion

Question 49

The largest value of the Henry's Law constant for the liquid solvent H₂O will be obtained with Gas as the solute and a temperature of °C.

A) Ar, 11
B) C₂H₄, 45
C) CO₂, 32
D) HCl, 49
E) N₂, 15

Question 50

Which one of the following concentration units varies with temperature?

A) mole fraction
B) mass percent
C) molarity
D) molality
E) all of the above

Question 51

The magnitudes of K_f and of K_b depend on the identity of the .

A) solvent and on temperature
B) solute and solvent
C) solvent
D) solute
E) solution

Question 52

At 20°C, an aqueous solution that is 24.00% by mass in ammonium chloride has a density of 1.0674 g/mL. What is the molarity of ammonium chloride in the solution? The formula weight of NH₄Cl is 53.50 g/mol.

A) 22.5
B) 4.79
C) 0.479
D) 5.90
E) 0.0445

Question 53

Which one of the following substances would be the most soluble in CCl₄?

A) C₁₀H₂₂
B) CH₃CH₂OH
C) H₂O
D) NaCl
E) NH₃

Question 54

Which one of the following is most soluble in water?

A) CH₃CH₂OH
B) CH₃CH₂CH₂CH₂OH
C) CH₃OH
D) CH₃CH₂CH₂OH
E) CH₃CH₂CH₂CH₂CH₂OH

Question 55

Which of the following substances is more likely to dissolve in CH₃OH?

A) N₂
B) Kr
C) CCl₄
D) H₂
E) CH₃CH₂OH

Question 56

Which of the following aqueous solutions will have the highest boiling point?

A) 0.10 m SrSO₄
B) 0.20 m glucose
C) 0.25 m sucrose
D) 0.10 m NaCl
E) 0.10 m Na₂SO₄

Question 57

Which of the following substances is more likely to dissolve in water?

A) HOCH₂CH₂OH
B) CH₃(CH₂)₈CH₂OH
C) CCl₄
D) CHCl₃
E)

Question 58

A solution contains 15 ppm of benzene. The density of the solution is 1.00 g/mL. This means that
)

A) there are 15 mg of benzene in 1.0 g of this solution
B) 1.0 L of the solution contains 15 g of benzene
C) the solution is 15% by mass of benzene
D) 1.0 g of the solution contains 15 × 10^{- 6} g of benzene
E) 100 g of the solution contains 15 g of benzene

Question 59

As the concentration of a solute in a solution increases, the freezing point of the solution
And the vapor pressure of the solution .

A) decreases, increases
B) decreases, is unaffected
C) increases, increases
D) decreases, decreases
E) increases, decreases

Question 60

Which of the following liquids will have the lowest freezing point?

A) pure H₂O
B) aqueous FeI₃ (0.24 m)
C) aqueous sucrose (0.60 m)
D) aqueous glucose (0.60 m)
E) aqueous KF (0.50 m)

Question 61

Water (H₂O) and the alcohol methanol (CH₃OH) are infinitely soluble in each other. The primary intermolecular force responsible for this is .

Question 62

A solution contains 150.8 grams of NaCl in 678.3 grams of water. Calculate the vapor pressure of water (in torr) over the solution at 25.0 ^oC. (Note:
the vapor pressure of pure water at 25.0 ^oC is 23.76 torr.)

Question 63

What is the osmotic pressure (in atm) of a 0.040 M solution of a non- electrolyte at 30.0 ^oC?

Question 64

Pressure has an appreciable effect on the solubility of in liquids.

A) solids
B) solids and liquids
C) liquids
D) salts
E) gases

Question 65

A sample of potassium nitrate (49.0 g) is dissolved in 101 g of water at 100 °C, with precautions taken to avoid evaporation of any water. The solution is cooled to 30.0 °C and no precipitate is observed. This solution is .

A) saturated
B) unsaturated
C) hydrated
D) placated
E) supersaturated

Question 66

The vapor pressure of pure water at 25 °C is 23.8 torr. What is the vapor pressure (torr) of water above a solution prepared by dissolving 18.0 g of glucose (anonelectrolyte, MW = 180.0 g/mol) in
95.0 g of water?

A) 0.443
B) 23.8
C) 24.3
D) 0.451
E) 23.4

Question 67

Which component of air is the primary problem in a condition known as "the bends?"

A) N₂
B) He
C) CO₂
D) CO
E) O₂

Question 68

Determine the fraction of ionization of HX if a solution prepared by dissolving 0.020 mol of HX in 115 g of water freezes at - 0.47 °C. The molal freezing- point- depression constant of water is
1)86 °C/m.

A) 1.45
B) 0.45
C) 0.044
D) 0.348
E) 0.30

Question 69

The concentration of HCl in a solution that is prepared by dissolving 5.5 g of HCl in 200 g of C₂H₆O is _ molal.

A) 1.3
B) 0.75
C) 27.5
D) 7.5 × 10^{- 4}
E) 3.3 × 10^{- 2}

Question 70

When two nonpolar organic liquids are mixed, a solution forms and the enthalpy of solution is quite small. Label the two organic liquids as A (solvent) and B (solute) The formation of solution is favored by .

A) the highly negative enthalpy of the solution process
B) an increase in disorder, since A- A, B- B, and A- B interactions are similar
C) solvation of the solvent, A
D) hydration of the solute, B
E) the equal enthalpy of the solvent and solute

Question 71

The mole fraction of urea (MW = 60.0 g/mol) in a solution prepared by dissolving 16 g of urea in 39 g of H₂O is _ .

A) 0.37
B) 0.58
C) 9.1
D) 0.13
E) 0.11

Question 72

Physical properties of a solution that depend on the quantity of the solute particles present, but not the kind or identity of the particles, are termed properties.

Question 73

A solution is prepared by dissolving 6.00 g of an unknown nonelectrolyte in enough water to make
1)00 L of solution. The osmotic pressure of this solution is 0.750 atm at 25.0 °C. What is the molecular weight (g/mol) of the unknown solute?

A) 16.4
B) 110
C) 5.12 × 10^{- 3}
D) 30.6
E) 195

Question 74

A sample of potassium chlorate (15.0 g) is dissolved in 201 g of water at 70 °C, with precautions taken to avoid evaporation of any water. The solution is cooled to 30.0 °C and no precipitate is observed. This solution is .

A) unsaturated
B) saturated
C) miscible
D) supersaturated
E) hydrated

Question 75

The phenomenon used to differentiate colloids and true solutions is called the effect.

Question 76

A solution is prepared by dissolving 0.60 g of nicotine (a nonelectrolyte) in water to make 12 mL of solution. The osmotic pressure of the solution is 7.55 atm at 25 °C. The molecular weight of nicotine is g/mol.

A) 43
B) 0.60
C) 160
D) 28
E) 50

Question 77

Calculate the freezing point (0°C) of a 0.05500 m aqueous solution of NaNO₃. The molal freezing- point- depression constant of water is 1.86 °C/m.

A) 0.1023
B) 0.0286
C) - 0.05627
D) - 0.1023
E) - 0.2046

Question 78

Which one of the following solutes has a limiting van't Hoff factor (i) of 3 when dissolved in water?

A) CCl₄
B) Na₂SO₄
C) sucrose
D) KNO₃
E) CH₃OH

Question 79

A solution contains 150.8 grams of NaCl in 678.3 grams of water. Calculate the vapor pressure lowering (in torr) of the solution at 25.0 ^oC. (Note:
the vapor pressure of pure water at 25.0 ^oC is 23.76 torr.)

Question 80

The concentration of KCl in a solution prepared by adding 0.0660 mol of KCl to 1.00 mol of water is
% by mass.

A) 0.733
B) 0.0130
C) 0.0519
D) 7.33 × 10^{- 4}
E) 5.19