Question 1

Identify the compound whose solubility is least affected by temperature.

Accepted Answer

A)  K Cl  
B)  K2Cr2O7 
C)  NaNO3 
D)  Pb(NO3)3 
E)  NaCl 
A)  K Cl  
B)  K2Cr2O7 
C)  NaNO3 
D)  Pb(NO3)3 
E)  NaCl E

Question 2

What volume of a 0.716 M KBr solution is needed to provide 30.5 g of KBr?

Accepted Answer

A)  21.8 mL 
B)  42.7 mL 
C)  184 mL 
D)  357 mL 
A)  21.8 mL 
B)  42.7 mL 
C)  184 mL 
D)  357 mL D

Question 3

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

Accepted Answer

A)  0.120 m C2H6O2 
B)  0.040 m (NH4)2SO4 
C)  0.060 m Li2CO3 
D)  0.030 m RbC2H3O2 
E)  They all have the same vapor pressure. 
A)  0.120 m C2H6O2 
B)  0.040 m (NH4)2SO4 
C)  0.060 m Li2CO3 
D)  0.030 m RbC2H3O2 
E)  They all have the same vapor pressure. C

Question 4

Choose the situation below that would result in an endothermic ΔHsolution.

Accepted Answer

A)  When   >   
B)  When   >   
E)  There isn't enough information to determine. 
A)  When   >   
B)  When   >   
E)  There isn't enough information to determine.

Question 5

Calculate the freezing point of a solution of 500.0 g of ethylene glycol (C2H6O2)dissolved in 500.0 g of water.Kf = 1.86°C/m and Kb = 0.512°C/m.

Accepted Answer

A)  30.0°C 
B)  -30.0°C 
C)  8.32°C 
D)  -8.32°C 
E)  70.2°C 
A)  30.0°C 
B)  -30.0°C 
C)  8.32°C 
D)  -8.32°C 
E)  70.2°C

Question 6

Determine DHsolute for KBr if the DHsolution (KBr)= +19.9 kJ/mol and the ΔHhydration(KBr)= -670.kJ/mol.

Accepted Answer

A)  +650 kJ/mol 
B)  -650 kJ/mol 
C)  +690 kJ/mol 
D)  -710 kJ/mol 
E)  -690 kJ/mol 
A)  +650 kJ/mol 
B)  -650 kJ/mol 
C)  +690 kJ/mol 
D)  -710 kJ/mol 
E)  -690 kJ/mol

Question 7

Determine the vapor pressure of a solution at 55°C that contains 34.2 g NaCl in 375 mL of water.The vapor pressure of pure water at 55°C is 118.1 torr.The van't Hoff factor for NaCl is 1.9.

Accepted Answer

A)  115 torr 
B)  87.1 torr 
C)  108 torr 
D)  112 torr 
E)  92.8 torr 
A)  115 torr 
B)  87.1 torr 
C)  108 torr 
D)  112 torr 
E)  92.8 torr

Question 8

A solution is prepared by dissolving 98.6 g of NaCl in enough water to form 875 mL of solution.Calculate the mass % of the solution if the density of the solution is 1.06 g/mL.

Accepted Answer

A)  11.3% 
B)  12.7% 
C)  9.4% 
D)  10.6% 
E)  11.9% 
A)  11.3% 
B)  12.7% 
C)  9.4% 
D)  10.6% 
E)  11.9%

Question 9

Dissolving can be defined as

Accepted Answer

A)  rate of dissolution = rate of deposition. 
B)  rate of dissolution  rate of deposition. 
D)  rate of bubbling > rate of dissolving 
E)  rate of condensing > rate of bubbling 
A)  rate of dissolution = rate of deposition. 
B)  rate of dissolution  rate of deposition. 
D)  rate of bubbling > rate of dissolving 
E)  rate of condensing > rate of bubbling

Question 10

Give the major force between acetone and chloroform.

Accepted Answer

A)  dipole-dipole 
B)  dispersion 
C)  hydrogen bonding 
D)  ion-ion 
E)  ion-dipole 
A)  dipole-dipole 
B)  dispersion 
C)  hydrogen bonding 
D)  ion-ion 
E)  ion-dipole

Question 11

Which of the following compounds will be most soluble in nonane (C9H20)?

Accepted Answer

A)  pentanol (CH3CH2CH2CH2CH2OH) 
B)  benzene (C6H6) 
C)  acetic acid (CH3CO2H) 
D)  ethyl methyl ketone (CH3CH2COH3) 
E)  None of these compounds should be soluble in pentane. 
A)  pentanol (CH3CH2CH2CH2CH2OH) 
B)  benzene (C6H6) 
C)  acetic acid (CH3CO2H) 
D)  ethyl methyl ketone (CH3CH2COH3) 
E)  None of these compounds should be soluble in pentane.

Question 12

What is the weight percent of vitamin C in a solution made by dissolving 6.50 g of vitamin C,C6H8O6,in 55.0 g of water?

Accepted Answer

A)  0.547% 
B)  1.21% 
C)  10.6% 
D)  11.8% 
A)  0.547% 
B)  1.21% 
C)  10.6% 
D)  11.8%

Question 13

What mass of NaCl is contained in 24.88 g of a 15.00% by mass solution of NaCl in water?

Accepted Answer

A)  20.00 g 
B)  21.15 g 
C)  3.73 g 
D)  1.50 g 
E)  12.44 g 
A)  20.00 g 
B)  21.15 g 
C)  3.73 g 
D)  1.50 g 
E)  12.44 g

Question 14

To make a 2.00 m 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 15

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 m 
B)  0.143 m 
C)  0.695 m 
D)  0.794 m 
A)  7.94 × 10-4 m 
B)  0.143 m 
C)  0.695 m 
D)  0.794 m

Question 16

A 150.0 mL sample of an aqueous solution at 25°C contains 15.2 mg of an unknown nonelectrolyte compound.If the solution has an osmotic pressure of 8.44 torr,what is the molar mass of the unknown compound?

Accepted Answer

A)  223 g/mol 
B)  294 g/mol 
C)  341 g/mol 
D)  448 g/mol 
E)  195 g/mol 
A)  223 g/mol 
B)  294 g/mol 
C)  341 g/mol 
D)  448 g/mol 
E)  195 g/mol

Question 17

Determine the vapor pressure of a solution at 25°C that contains 76.6 g of glucose (C6H12O6)in 250.0 mL of water.The vapor pressure of pure water at 25°C is 23.8 torr.

Accepted Answer

A)  70.8 torr 
B)  72.9 torr 
C)  23.1 torr 
D)  22.9 torr 
E)  7.29 torr 
A)  70.8 torr 
B)  72.9 torr 
C)  23.1 torr 
D)  22.9 torr 
E)  7.29 torr

Question 18

What is the mole fraction of acetone,(CH3)2CO,in a solution containing 500 g of acetone in 800 g of benzene,C6H6?

Accepted Answer

A)  0.841 
B)  0.457 
C)  0.314 
D)  0.227 
A)  0.841 
B)  0.457 
C)  0.314 
D)  0.227

Question 19

What mass of water is required to give an aqueous solution containing 0.265 mol of MgCl2 with a freezing point of -3.8°C? (Van't Hoff factor of MgCl2 is 2.7)

Accepted Answer

A)  1.25 kg 
B)  0.538 kg 
C)  0.113 kg 
D)  0.882 kg 
E)  0.350 kg 
A)  1.25 kg 
B)  0.538 kg 
C)  0.113 kg 
D)  0.882 kg 
E)  0.350 kg

Question 20

A solution of LiCl in water has XLiCl = 0.0900.What is the molality?

Accepted Answer

A)  4.46 m LiCl 
B)  5.00 m LiCl 
C)  5.49 m LiCl 
D)  9.89 m LiCl 
A)  4.46 m LiCl 
B)  5.00 m LiCl 
C)  5.49 m LiCl 
D)  9.89 m LiCl

Exam 14: Solutions

Identify the compound whose solubility is least affected by temperature.

What volume of a 0.716 M KBr solution is needed to provide 30.5 g of KBr?

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

Choose the situation below that would result in an endothermic ΔHsolution.

Calculate the freezing point of a solution of 500.0 g of ethylene glycol (C2H6O2)dissolved in 500.0 g of water.Kf = 1.86°C/m and Kb = 0.512°C/m.

Determine DHsolute for KBr if the DHsolution (KBr)= +19.9 kJ/mol and the ΔHhydration(KBr)= -670.kJ/mol.

Determine the vapor pressure of a solution at 55°C that contains 34.2 g NaCl in 375 mL of water.The vapor pressure of pure water at 55°C is 118.1 torr.The van't Hoff factor for NaCl is 1.9.

A solution is prepared by dissolving 98.6 g of NaCl in enough water to form 875 mL of solution.Calculate the mass % of the solution if the density of the solution is 1.06 g/mL.

Dissolving can be defined as

Give the major force between acetone and chloroform.

Which of the following compounds will be most soluble in nonane (C9H20)?

What is the weight percent of vitamin C in a solution made by dissolving 6.50 g of vitamin C,C6H8O6,in 55.0 g of water?

What mass of NaCl is contained in 24.88 g of a 15.00% by mass solution of NaCl in water?

To make a 2.00 m solution,one could take 2.00 moles of solute and add

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

A 150.0 mL sample of an aqueous solution at 25°C contains 15.2 mg of an unknown nonelectrolyte compound.If the solution has an osmotic pressure of 8.44 torr,what is the molar mass of the unknown compound?

Determine the vapor pressure of a solution at 25°C that contains 76.6 g of glucose (C6H12O6)in 250.0 mL of water.The vapor pressure of pure water at 25°C is 23.8 torr.

What is the mole fraction of acetone,(CH3)2CO,in a solution containing 500 g of acetone in 800 g of benzene,C6H6?

What mass of water is required to give an aqueous solution containing 0.265 mol of MgCl2 with a freezing point of -3.8°C? (Van't Hoff factor of MgCl2 is 2.7)

A solution of LiCl in water has XLiCl = 0.0900.What is the molality?

Essentials: Units, Measurements, and Problem Solving

Atoms

The Quantum Mechanical Model of the Atom

Periodic Properties of the Elements

Molecules and Compounds

Chemical Bonding I

Chemical Bonding Ii

Chemical Reactions and Chemical Quantities

Introduction to Solutions and Aqueous Reactions

Thermochemistry

Gases

Liquids, Solids, and Intermolecular Forces

Crystalline Solids and Modern Materials

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Free Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry

Transition Metals and Coordination Compounds

Filters

Choose the situation below that would result in an endothermic ΔH_solution.

Calculate the freezing point of a solution of 500.0 g of ethylene glycol (C₂H₆O₂)dissolved in 500.0 g of water.K_f = 1.86°C/m and K_b = 0.512°C/m.

Determine DH_solute for KBr if the DH_solution(KBr)= +19.9 kJ/mol and the ΔH_hydration(KBr)= -670.kJ/mol.

Which of the following compounds will be most soluble in nonane (C₉H₂₀)?

What is the weight percent of vitamin C in a solution made by dissolving 6.50 g of vitamin C,C₆H₈O₆,in 55.0 g of water?

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

Determine the vapor pressure of a solution at 25°C that contains 76.6 g of glucose (C₆H₁₂O₆)in 250.0 mL of water.The vapor pressure of pure water at 25°C is 23.8 torr.

What is the mole fraction of acetone,(CH₃)₂CO,in a solution containing 500 g of acetone in 800 g of benzene,C₆H₆?

What mass of water is required to give an aqueous solution containing 0.265 mol of MgCl₂ with a freezing point of -3.8°C? (Van't Hoff factor of MgCl₂ is 2.7)

A solution of LiCl in water has X_LiCl = 0.0900.What is the molality?