Question 1

Which of the following compounds is most soluble in hexane (CH3CH2CH2CH2CH2CH2CH3)?

Accepted Answer

A) methanol 
B) ethanol 
C) 1-propanol 
D) 1-butanol 
E) 1-pentanol 
A) methanol 
B) ethanol 
C) 1-propanol 
D) 1-butanol 
E) 1-pentanol

Question 2

Calculate the mole fraction of MgCl2 in an aqueous solution prepared by dissolving 0.400 moles of MgCl2 in 850.0 g of water.

Accepted Answer

A) 0.00841 
B) 0.0270 
C) 0.00900 
D) 0.0252 
E) 0.0167 
A) 0.00841 
B) 0.0270 
C) 0.00900 
D) 0.0252 
E) 0.0167

Question 3

Calculate the mass of lactose, C12H22O11, contained in 500.0 mL of solution if the measured vapour pressure of the solution is 121.2 mbar at 50 °C. The vapour pressure of pure water at 50 °C is 123.3 mbar; assume no change in volume occurs upon dissolution.

Accepted Answer

A) 118 g 
B) 165 g 
C) 239 g 
D) 94.6 g 
E) 280 g 
A) 118 g 
B) 165 g 
C) 239 g 
D) 94.6 g 
E) 280 g

Question 4

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 vapour pressure of pure water at 55 °C is 0.1553 bar. The MW of lactose is 342.3 g mol-1.

Accepted Answer

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

Question 5

Match the following.

-0.020 mol kg-1 NH4Cl

Accepted Answer

A) largest van't Hoff factor 
B) solution that is most strongly dependent upon pressure 
C) solution of ionic compound with highest freezing point. 
D) highest boiling point 
E) solution with ΔTb = 0.026 °C 
A) largest van't Hoff factor 
B) solution that is most strongly dependent upon pressure 
C) solution of ionic compound with highest freezing point. 
D) highest boiling point 
E) solution with ΔTb = 0.026 °C

Question 6

A compound is found to have a molar mass of 190 g mol-1. If 0.0673 g of the compound is dissolved in enough water to make 200 mL of solution at 25 °C, what is the osmotic pressure of the resulting solution?

Accepted Answer

A) 1.21 × 10-2 bar 
B) 6.12 × 10-2 bar 
C) 4.39 × 10-2 bar 
D) 3.97 × 10-2 bar 
E) 2.28 × 10-2 bar 
A) 1.21 × 10-2 bar 
B) 6.12 × 10-2 bar 
C) 4.39 × 10-2 bar 
D) 3.97 × 10-2 bar 
E) 2.28 × 10-2 bar

Question 7

Identify the classification of milk.

Accepted Answer

A) aerosol 
B) solid aerosol 
C) foam 
D) emulsion 
E) solid emulsion 
A) aerosol 
B) solid aerosol 
C) foam 
D) emulsion 
E) solid emulsion

Question 8

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

Accepted Answer

The hydrated Mg²⁺ and Cl⁻ ions

Question 9

What is the molality of a glucose solution prepared by dissolving 18.0 g of glucose, C6H12O6, in 125.9 g of water?

Accepted Answer

A) 7.94 × 10-4 mol kg-1 
B) 0.143 mol kg-1 
C) 0.695 mol kg-1 
D) 0.794 mol kg-1 
A) 7.94 × 10-4 mol kg-1 
B) 0.143 mol kg-1 
C) 0.695 mol kg-1 
D) 0.794 mol kg-1

Question 10

To make a 2.00 mol kg-1 solution, one could take 2.00 moles of solute and add

Accepted Answer

A) 1.00 L of solvent. 
B) 1.00 kg of solvent. 
C) enough solvent to make 1.00 L of solution. 
D) enough solvent to make 1.00 kg of solution. 
A) 1.00 L of solvent. 
B) 1.00 kg of solvent. 
C) enough solvent to make 1.00 L of solution. 
D) enough solvent to make 1.00 kg of solution.

Question 11

Calculate the mass of maltose, C12H22O11, contained in 725.0 mL of solution if the measured vapour pressure of the solution is 41.6 mbar at 30 °C. The vapour pressure of pure water at 30 °C is 42.40 mbar; assume no change in volume occurs upon dissolution.

Accepted Answer

A) 482 g 
B) 329 g 
C) 265 g 
D) 163 g 
E) 94.1 g 
A) 482 g 
B) 329 g 
C) 265 g 
D) 163 g 
E) 94.1 g

Question 12

Choose the situation below that would result in an exothermic ΔsolutionH.

Accepted Answer

A) when   >   
B) when   is close to   
C) when      
E) There isn't enough information to determine the answer. 
A) when   >   
B) when   is close to   
C) when      
E) There isn't enough information to determine the answer.

Question 13

Define a colloid.

Accepted Answer

A colloid is a mixtu

Question 14

The boiling point of an aqueous 1.83 mol kg-1 (NH4)2SO4 (molar mass = 132.15 g mol-1)solution is 102.5 °C. Determine the value of the van't Hoff factor for this solute if the Kb for water is 0.512 °C m-1.

Accepted Answer

A) 3.0 
B) 3.6 
C) 1.8 
D) 2.7 
E) 2.3 
A) 3.0 
B) 3.6 
C) 1.8 
D) 2.7 
E) 2.3

Question 15

Twice as much pentane (C5H12)is mixed with hexane (C6H14)by mass. Calculate the vapour pressure of the resulting solution. The vapour pressures of pure pentane and hexane are 425 Torr and 151 Torr, respectively. Assume ideal behaviour.

Accepted Answer

A) 386 Torr 
B) 300 Torr 
C) 311 Torr 
D) 253 Torr 
E) 344 Torr 
A) 386 Torr 
B) 300 Torr 
C) 311 Torr 
D) 253 Torr 
E) 344 Torr

Question 16

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

Accepted Answer

A) 0.100 mol kg-1 NaNO3 
B) 0.100 mol kg-1 Li2SO4 
C) 0.200 mol kg-1 C3H8O3 
D) 0.060 mol kg-1 Na3PO4 
E) They all have the same boiling point. 
A) 0.100 mol kg-1 NaNO3 
B) 0.100 mol kg-1 Li2SO4 
C) 0.200 mol kg-1 C3H8O3 
D) 0.060 mol kg-1 Na3PO4 
E) They all have the same boiling point.

Question 17

Identify the gas that is dissolved in carbonated sodas.

Accepted Answer

A) carbon dioxide 
B) oxygen 
C) nitrogen 
D) carbon monoxide 
E) hydrogen 
A) carbon dioxide 
B) oxygen 
C) nitrogen 
D) carbon monoxide 
E) hydrogen

Question 18

Identify the solute with the highest van't Hoff factor.

Accepted Answer

A) nonelectrolyte 
B) NaCl 
C) MgSO4 
D) MgCl2 
E) FeCl3 
A) nonelectrolyte 
B) NaCl 
C) MgSO4 
D) MgCl2 
E) FeCl3

Question 19

A 125.0 mL sample of an aqueous solution at 25 °C contains 29.4 mg of an unknown nonelectrolyte compound. If the solution has an osmotic pressure of 24.4 mbar, what is the molar mass of the unknown compound?

Accepted Answer

A) 116 g mol-1 
B) 281 g mol-1 
C) 239 g mol-1 
D) 98.6 g mol-1 
E) 311 g mol-1 
A) 116 g mol-1 
B) 281 g mol-1 
C) 239 g mol-1 
D) 98.6 g mol-1 
E) 311 g mol-1

Question 20

Match the following.

-0.010 mol kg-1 Al(NO3)3

Accepted Answer

A) largest van't Hoff factor 
B) solution that is most strongly dependent upon pressure 
C) solution of ionic compound with highest freezing point. 
D) highest boiling point 
E) solution with ΔTb = 0.026 °C 
A) largest van't Hoff factor 
B) solution that is most strongly dependent upon pressure 
C) solution of ionic compound with highest freezing point. 
D) highest boiling point 
E) solution with ΔTb = 0.026 °C

Exam 12: Solutions

Which of the following compounds is most soluble in hexane (CH3CH2CH2CH2CH2CH2CH3)?

Calculate the mole fraction of MgCl2 in an aqueous solution prepared by dissolving 0.400 moles of MgCl2 in 850.0 g of water.

Calculate the mass of lactose, C12H22O11, contained in 500.0 mL of solution if the measured vapour pressure of the solution is 121.2 mbar at 50 °C. The vapour pressure of pure water at 50 °C is 123.3 mbar; assume no change in volume occurs upon dissolution.

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 vapour pressure of pure water at 55 °C is 0.1553 bar. The MW of lactose is 342.3 g mol-1.

Match the following. -0.020 mol kg-1 NH4Cl

A compound is found to have a molar mass of 190 g mol-1. If 0.0673 g of the compound is dissolved in enough water to make 200 mL of solution at 25 °C, what is the osmotic pressure of the resulting solution?

Identify the classification of milk.

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

What is the molality of a glucose solution prepared by dissolving 18.0 g of glucose, C6H12O6, in 125.9 g of water?

To make a 2.00 mol kg-1 solution, one could take 2.00 moles of solute and add

Calculate the mass of maltose, C12H22O11, contained in 725.0 mL of solution if the measured vapour pressure of the solution is 41.6 mbar at 30 °C. The vapour pressure of pure water at 30 °C is 42.40 mbar; assume no change in volume occurs upon dissolution.

Choose the situation below that would result in an exothermic ΔsolutionH.

Define a colloid.

The boiling point of an aqueous 1.83 mol kg-1 (NH4)2SO4 (molar mass = 132.15 g mol-1)solution is 102.5 °C. Determine the value of the van't Hoff factor for this solute if the Kb for water is 0.512 °C m-1.

Twice as much pentane (C5H12)is mixed with hexane (C6H14)by mass. Calculate the vapour pressure of the resulting solution. The vapour pressures of pure pentane and hexane are 425 Torr and 151 Torr, respectively. Assume ideal behaviour.

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

Identify the gas that is dissolved in carbonated sodas.

Identify the solute with the highest van't Hoff factor.

A 125.0 mL sample of an aqueous solution at 25 °C contains 29.4 mg of an unknown nonelectrolyte compound. If the solution has an osmotic pressure of 24.4 mbar, what is the molar mass of the unknown compound?

Match the following. -0.010 mol kg-1 Al(NO3)3

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules, Compounds, and Nomenclature

Chemical Reactions and Stoichiometry

Gases

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding Ii: Molecular Shapes, Valence Bond Theory, and Molecular Orbital Theory

Liquids, Solids, and Intermolecular Forces

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry II: Reactions

Biochemistry

Chemistry of the Nonmetals

Metals and Metallury

Transition Metals and Coordination Compounds

Filters

Which of the following compounds is most soluble in hexane (CH₃CH₂CH₂CH₂CH₂CH₂CH₃)?

Calculate the mole fraction of MgCl₂ in an aqueous solution prepared by dissolving 0.400 moles of MgCl₂ in 850.0 g of water.

Calculate the mass of lactose, C₁₂H₂₂O₁₁, contained in 500.0 mL of solution if the measured vapour pressure of the solution is 121.2 mbar at 50 °C. The vapour pressure of pure water at 50 °C is 123.3 mbar; assume no change in volume occurs upon dissolution.

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 vapour pressure of pure water at 55 °C is 0.1553 bar. The MW of lactose is 342.3 g mol^-1.

Match the following. -0.020 mol kg^-1 NH₄Cl

A compound is found to have a molar mass of 190 g mol^-1. If 0.0673 g of the compound is dissolved in enough water to make 200 mL of solution at 25 °C, what is the osmotic pressure of the resulting solution?

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

What is the molality of a glucose solution prepared by dissolving 18.0 g of glucose, C₆H₁₂O₆, in 125.9 g of water?

To make a 2.00 mol kg^-1 solution, one could take 2.00 moles of solute and add

Calculate the mass of maltose, C₁₂H₂₂O₁₁, contained in 725.0 mL of solution if the measured vapour pressure of the solution is 41.6 mbar at 30 °C. The vapour pressure of pure water at 30 °C is 42.40 mbar; assume no change in volume occurs upon dissolution.

Choose the situation below that would result in an exothermic Δ_solutionH.

The boiling point of an aqueous 1.83 mol kg^-1 (NH₄)₂SO₄ (molar mass = 132.15 g mol^-1)solution is 102.5 °C. Determine the value of the van't Hoff factor for this solute if the K_b for water is 0.512 °C m^-1.

Twice as much pentane (C₅H₁₂)is mixed with hexane (C₆H₁₄)by mass. Calculate the vapour pressure of the resulting solution. The vapour pressures of pure pentane and hexane are 425 Torr and 151 Torr, respectively. Assume ideal behaviour.

Match the following. -0.010 mol kg^-1 Al(NO₃)₃