Question 1

Which of the following statements is generally TRUE?

Accepted Answer

A)  The solubility of a solid is not dependent on either temperature or pressure. 
B)  The solubility of a solid is highly dependent on pressure. 
C)  The solubility of a solid is highly dependent on both pressure and temperature. 
D)  The solubility of a solid is highly dependent on temperature. 
E)  None of the above. 
A)  The solubility of a solid is not dependent on either temperature or pressure. 
B)  The solubility of a solid is highly dependent on pressure. 
C)  The solubility of a solid is highly dependent on both pressure and temperature. 
D)  The solubility of a solid is highly dependent on temperature. 
E)  None of the above.

Question 2

Choose the aqueous solution below with the lowest freezing point.These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.

Accepted Answer

A)  0.075 m Li Cl 
B)  0.075 m (NH4)3PO4 
C)  0.075 m NaBrO4 
D)  0.075 m KCN 
E)  0.075 m KNO2 
A)  0.075 m Li Cl 
B)  0.075 m (NH4)3PO4 
C)  0.075 m NaBrO4 
D)  0.075 m KCN 
E)  0.075 m KNO2

Question 3

A solution is 0.0480 m LiF.What is the molarity of the solution if the density is 1.10 g/mL?

Accepted Answer

A)  0.0441 M 
B)  0.0480 M 
C)  0.0436 M 
D)  0.0528 M 
E)  0.0417 M 
A)  0.0441 M 
B)  0.0480 M 
C)  0.0436 M 
D)  0.0528 M 
E)  0.0417 M

Question 4

Match between columns
                        Premises: 0.020 m NHS1U1B14S1U1B0Cl
0.0050 m COS1U1B12S1U1B0
0.050 m NaCl
0.010 m Al(NOS1U1B13S1U1B0)S1U1B13S1U1B0
0.050 m CS1U1B16S1U1B0HS1U1B112S1U1B0OS1U1B16 S1U1B0(aqueous)

Accepted Answer

The Answer of largest van't Hoff factor and solution that is...

Question 5

How many moles of KF are contained in 347 g of water in a 0.175 m KF solution?

Accepted Answer

A)  1.65 × 10-2 mol KF 
B)  5.04 × 10-2 mol KF 
C)  6.07 × 10-2 mol KF 
D)  3.22 × 10-2 mol KF 
E)  1.98 × 10-2 mol KF 
A)  1.65 × 10-2 mol KF 
B)  5.04 × 10-2 mol KF 
C)  6.07 × 10-2 mol KF 
D)  3.22 × 10-2 mol KF 
E)  1.98 × 10-2 mol KF

Question 6

A 4.55 L sample of water contains 0.115 g of sodium ions.Determine the concentration of sodium ions in ppm if the density of the solution is 1.00 g/mL.

Accepted Answer

A)  52.3 ppm 
B)  13.2 ppm 
C)  12.7 ppm 
D)  25.3 ppm 
E)  36.5 ppm 
A)  52.3 ppm 
B)  13.2 ppm 
C)  12.7 ppm 
D)  25.3 ppm 
E)  36.5 ppm

Question 7

Calculate the molality of a solution formed by dissolving 34.8 g of LiI in 500.0 mL of water.

Accepted Answer

A)  0.254 m 
B)  0.130 m 
C)  0.696 m 
D)  0.260 m 
E)  0.520 m 
A)  0.254 m 
B)  0.130 m 
C)  0.696 m 
D)  0.260 m 
E)  0.520 m

Question 8

Choose the aqueous solution below with the highest freezing point.These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.

Accepted Answer

A)  0.200 m Mg(ClO4)2 
B)  0.200 m Na3PO3 
C)  0.200 m HOCH2CH2OH 
D)  0.200 m Ba(NO3)2 
E)  These all have the same freezing point. 
A)  0.200 m Mg(ClO4)2 
B)  0.200 m Na3PO3 
C)  0.200 m HOCH2CH2OH 
D)  0.200 m Ba(NO3)2 
E)  These all have the same freezing point.

Question 9

What is the freezing point of a solution of 7.15 g MgCl2 in 100 g of water? Kf for water is1.86°C/m.

Accepted Answer

A)  -0.140°C 
B)  - 1.40°C 
C)  - 2.80°C 
D)  - 4.18°C 
A)  -0.140°C 
B)  - 1.40°C 
C)  - 2.80°C 
D)  - 4.18°C

Question 10

A solution is prepared by dissolving 76.3 g NaI in 545 g of water.Determine the mole fraction of NaI if the final volume of the solution is 576 mL.

Accepted Answer

A)  6.04 × 10-3 
B)  1.65 × 10-2 
C)  1.40 × 10-3 
D)  1.32 × 10-2 
E)  8.84 × 10-2 
A)  6.04 × 10-3 
B)  1.65 × 10-2 
C)  1.40 × 10-3 
D)  1.32 × 10-2 
E)  8.84 × 10-2

Question 11

A solution is prepared by dissolving 1.928 g of KNO3 into enough water to make 651 mL.What is the molarity of the solution?

Accepted Answer

A)  0.159 M 
B)  0.381 M 
C)  0.0293 M 
D)  2.48 M 
E)  0.0832 M 
A)  0.159 M 
B)  0.381 M 
C)  0.0293 M 
D)  2.48 M 
E)  0.0832 M

Question 12

Choose the statement below that is TRUE.

Accepted Answer

A)  A solution will form between two substances if the solute-solvent interactions are of comparable strength to the solute-solute and solvent-solvent interactions. 
B)  A solution will form between two substances if the solute-solvent interactions are small enough to be overcome by the solute-solute and solvent-solvent interactions. 
C)  A solution will form between two substances if the solute-solute interactions are strong enough to overcome the solvent-solvent interactions. 
D)  A solution will form between two substances only if the solvent-solvent interactions are weak enough to overcome the solute-solvent interactions. 
E)  None of the above are true. 
A)  A solution will form between two substances if the solute-solvent interactions are of comparable strength to the solute-solute and solvent-solvent interactions. 
B)  A solution will form between two substances if the solute-solvent interactions are small enough to be overcome by the solute-solute and solvent-solvent interactions. 
C)  A solution will form between two substances if the solute-solute interactions are strong enough to overcome the solvent-solvent interactions. 
D)  A solution will form between two substances only if the solvent-solvent interactions are weak enough to overcome the solute-solvent interactions. 
E)  None of the above are true.

Question 13

Calculate the mole fraction of the total ions in an aqueous solution prepared by dissolving 0.400 moles of Ca F2 in 850.0 g of water.

Accepted Answer

A)  0.00841 
B)  0.0270 
C)  0.00900 
D)  0.0248 
E)  0.0167 
A)  0.00841 
B)  0.0270 
C)  0.00900 
D)  0.0248 
E)  0.0167

Question 14

What is the expected freezing point of a 0.50 m solution of Li2SO4 in water? Kf for water is 1.86°C/m.

Accepted Answer

A)  -0.93°C 
B)  -1.9°C 
C)  -2.8°C 
D)  -6.5°C 
A)  -0.93°C 
B)  -1.9°C 
C)  -2.8°C 
D)  -6.5°C

Question 15

Determine the solubility of N2 in water exposed to air at 25°C if the atmospheric pressure is 2.0 atm.Assume that the mole fraction of nitrogen is 0.78 in air and the Henry's law constant for nitrogen in water at this temperature is 6.1 × 10-4 M/atm.

Accepted Answer

A)  1.6 × 10-4 M 
B)  6.4 × 10-4 M 
C)  9.5 × 10-4 M 
D)  1.1 × 10-4 M 
E)  1.2 × 10-4 M 
A)  1.6 × 10-4 M 
B)  6.4 × 10-4 M 
C)  9.5 × 10-4 M 
D)  1.1 × 10-4 M 
E)  1.2 × 10-4 M

Question 16

A solution of LiCl in water is 20.0 wt% LiCl.What is the mole fraction of LiCl?

Accepted Answer

A)  0.0960 
B)  0.106 
C)  0.472 
D)  4.44 
A)  0.0960 
B)  0.106 
C)  0.472 
D)  4.44

Question 17

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C7H6O2,dissolved in 800.g of benzene,C6H6.Kf for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

Accepted Answer

A)  - 2.09°C 
B)  2.09°C 
C)  3.41°C 
D)  7.59°C 
A)  - 2.09°C 
B)  2.09°C 
C)  3.41°C 
D)  7.59°C

Question 18

The vapor pressure of a solution is always that of the pure solvent

Accepted Answer

A)  equal to 
B)  twice 
C)  one half 
D)  higher than 
E)  lower than 
A)  equal to 
B)  twice 
C)  one half 
D)  higher than 
E)  lower than

Question 19

Identify the compound whose solubility decreases with increasing temperature.

Accepted Answer

A)  Na2SO4 
B)  K2Cr2O7 
C)  NaNO3 
D)  KClO3 
E)  CaCl2 
A)  Na2SO4 
B)  K2Cr2O7 
C)  NaNO3 
D)  KClO3 
E)  CaCl2

Question 20

Explain why the van't Hoff factor for MgCl2 is less than it's predicted value.

Accepted Answer

The hydrated Mg²⁺ and Cl⁻ ions

Exam 14: Solutions

Which of the following statements is generally TRUE?

Choose the aqueous solution below with the lowest freezing point.These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.

A solution is 0.0480 m LiF.What is the molarity of the solution if the density is 1.10 g/mL?

How many moles of KF are contained in 347 g of water in a 0.175 m KF solution?

A 4.55 L sample of water contains 0.115 g of sodium ions.Determine the concentration of sodium ions in ppm if the density of the solution is 1.00 g/mL.

Calculate the molality of a solution formed by dissolving 34.8 g of LiI in 500.0 mL of water.

Choose the aqueous solution below with the highest freezing point.These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable.

What is the freezing point of a solution of 7.15 g MgCl2 in 100 g of water? Kf for water is1.86°C/m.

A solution is prepared by dissolving 76.3 g NaI in 545 g of water.Determine the mole fraction of NaI if the final volume of the solution is 576 mL.

A solution is prepared by dissolving 1.928 g of KNO3 into enough water to make 651 mL.What is the molarity of the solution?

Choose the statement below that is TRUE.

Calculate the mole fraction of the total ions in an aqueous solution prepared by dissolving 0.400 moles of Ca F2 in 850.0 g of water.

What is the expected freezing point of a 0.50 m solution of Li2SO4 in water? Kf for water is 1.86°C/m.

Determine the solubility of N2 in water exposed to air at 25°C if the atmospheric pressure is 2.0 atm.Assume that the mole fraction of nitrogen is 0.78 in air and the Henry's law constant for nitrogen in water at this temperature is 6.1 × 10-4 M/atm.

A solution of LiCl in water is 20.0 wt% LiCl.What is the mole fraction of LiCl?

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C7H6O2,dissolved in 800.g of benzene,C6H6.Kf for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

The vapor pressure of a solution is always that of the pure solvent

Identify the compound whose solubility decreases with increasing temperature.

Explain why the van't Hoff factor for MgCl2 is less than it's predicted value.

Essentials: Units, Measurements, and Problem Solving

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The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

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Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

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Liquids, Solids, and Intermolecular Forces

Crystalline Solids and Modern Materials

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What is the freezing point of a solution of 7.15 g MgCl₂ in 100 g of water? K_f for water is1.86°C/m.

Calculate the mole fraction of the total ions in an aqueous solution prepared by dissolving 0.400 moles of Ca F₂ in 850.0 g of water.

What is the expected freezing point of a 0.50 m solution of Li₂SO₄ in water? K_f for water is 1.86°C/m.

Determine the solubility of N₂ in water exposed to air at 25°C if the atmospheric pressure is 2.0 atm.Assume that the mole fraction of nitrogen is 0.78 in air and the Henry's law constant for nitrogen in water at this temperature is 6.1 × 10^-4 M/atm.

Calculate the freezing point of a solution of 40.0 g methyl salicylate,C₇H₆O₂,dissolved in 800.g of benzene,C₆H₆.K_f for benzene is 5.10°C/m and the freezing point is 5.50°C for benzene.

Explain why the van't Hoff factor for MgCl₂ is less than it's predicted value.