Question 1

Red blood cells are placed into pure water.Which of the following statements is true?

Accepted Answer

A) Water molecules flow out of the red blood cells,causing them to collapse. 
B) Water flows into the red blood cells,causing them to swell and burst. 
C) The osmotic pressure of the cell contents increases,causing the cells to burst. 
D) The osmotic pressure inside the cells equals the osmotic pressure outside. 
A) Water molecules flow out of the red blood cells,causing them to collapse. 
B) Water flows into the red blood cells,causing them to swell and burst. 
C) The osmotic pressure of the cell contents increases,causing the cells to burst. 
D) The osmotic pressure inside the cells equals the osmotic pressure outside.

Question 2

The average osmotic pressure of blood is about 7 atm.Therefore

Accepted Answer

A) the average blood pressure is about 7 atm. 
B) the average pressure inside the body is about 7 atm above the external pressure. 
C) a pressure of about 7 atm would be required to prevent osmosis if blood is in contact with pure water across a semipermeable membrane. 
D) All of these are true. 
A) the average blood pressure is about 7 atm. 
B) the average pressure inside the body is about 7 atm above the external pressure. 
C) a pressure of about 7 atm would be required to prevent osmosis if blood is in contact with pure water across a semipermeable membrane. 
D) All of these are true.

Question 3

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in ________ solvents,whereas nonpolar substances like I2 are more soluble in ________ solvents.

Accepted Answer

Question 4

What is the mole fraction of I2 in a solution made by dissolving 27.8 g of I2 in 260 g of hexane,C6H14?

Accepted Answer

A) 0.0350 
B) 0.965 
C) 1.03 
D) 28.57 
A) 0.0350 
B) 0.965 
C) 1.03 
D) 28.57

Question 5

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water Kb = 0.51°C/m and Kf = 1.86°C/m.

Accepted Answer

A) -0.69°C 
B) -2.5°C 
C) -3.6°C 
D) -9.1°C 
A) -0.69°C 
B) -2.5°C 
C) -3.6°C 
D) -9.1°C

Question 6

An aqueous solution has a normal boiling point of 105.0°C.What is the freezing point of this solution? For water Kb is 0.51°C/m and Kf = 1.86°C/m.

Accepted Answer

A) 14.7°C 
B) -14.7°C 
C) 18.2°C 
D) -18.2°C 
A) 14.7°C 
B) -14.7°C 
C) 18.2°C 
D) -18.2°C

Question 7

What is the weight percent of vitamin C in a solution made by dissolving 8.00 g of vitamin C,C6H8O6,in 55.0 g of water?

Accepted Answer

A) 87.3% 
B) 14.5% 
C) 12.7% 
D) 85.5% 
A) 87.3% 
B) 14.5% 
C) 12.7% 
D) 85.5%

Question 8

What is the weight percent of vitamin C in a solution made by dissolving 1.30 g of vitamin C,C6H8O6,in 55.0 g of water?

Accepted Answer

A) 0.195% 
B) 0.242% 
C) 2.31% 
D) 2.36% 
A) 0.195% 
B) 0.242% 
C) 2.31% 
D) 2.36%

Question 9

A solution of 62.4 g of insulin in enough water to make 1.000 L of solution has an osmotic pressure of 0.305 atm at 25°C.Based on these data,what is the molar mass of insulin?

Accepted Answer

A) 621 g/mol 
B) 5000 g/mol 
C) 7570 g/mol 
D) 71,900 g/mol 
A) 621 g/mol 
B) 5000 g/mol 
C) 7570 g/mol 
D) 71,900 g/mol

Question 10

What is the freezing point of a solution of 8.00 g MgCl2 in 100 g of water? Kf for water is 1.86°C/m for water.

Accepted Answer

A) 1.56°C 
B) -1.56°C 
C) 4.69°C 
D) -4.69°C 
A) 1.56°C 
B) -1.56°C 
C) 4.69°C 
D) -4.69°C

Question 11

Assuming that sea water is a 3.5 wt % solution of NaCl in water,calculate its osmotic pressure at 20°C.The density of a 3.5% NaCl solution at 20°C is 1.023 g/mL.

Accepted Answer

A) 1.0 atm 
B) 15 atm 
C) 29 atm 
D) 100 atm 
A) 1.0 atm 
B) 15 atm 
C) 29 atm 
D) 100 atm

Question 12

The following diagram shows a close-up view of the vapor pressure curves for two pure liquids and two different solutions composed of these two liquids.Which curves represent pure liquids and which curves represent the solutions?

Accepted Answer

A) Curves (a)and (b)are the pure liquids and curves (c)and (d)are the solutions. 
B) Curves (a)and (c)are the pure liquids and curves (b)and (d)are the solutions. 
C) Curves (a)and (d)are the pure liquids and curves (b)and (c)are the solutions. 
D) Curves (c)and (d)are the pure liquids and curves (a)and (b)are the solutions. 
A) Curves (a)and (b)are the pure liquids and curves (c)and (d)are the solutions. 
B) Curves (a)and (c)are the pure liquids and curves (b)and (d)are the solutions. 
C) Curves (a)and (d)are the pure liquids and curves (b)and (c)are the solutions. 
D) Curves (c)and (d)are the pure liquids and curves (a)and (b)are the solutions.

Question 13

Drawing (1)shows a system in which an equilibrium exists between dissolved and undissolved gas particles at P = 1 atm.According to Henry's law,if the pressure is decreased to 0.5 atm and equilibrium is restored,which drawing (2)-(5)best represents the equilibrium at 0.5 atm?

Accepted Answer

A) drawing (2) 
B) drawing (3) 
C) drawing (4) 
D) drawing (5) 
A) drawing (2) 
B) drawing (3) 
C) drawing (4) 
D) drawing (5)

Question 14

A solution is 4.50% by weight NaHCO3.How many grams of NaHCO3 are in 450.0 g of solution?

Accepted Answer

A) 1.000 g 
B) 20.2 g 
C) 400 g 
D) 450 g 
A) 1.000 g 
B) 20.2 g 
C) 400 g 
D) 450 g

Question 15

Which of the following aqueous salt (NaCl)solutions has the greater concentration?

Accepted Answer

A) 0.5 M 
B) 2.3 m 
C) 3.0 % by mass 
D) 11.1 g/L 
A) 0.5 M 
B) 2.3 m 
C) 3.0 % by mass 
D) 11.1 g/L

Question 16

When 0.500 g of vitamin K is dissolved in 10.0 g of camphor (Kf = 40.0°C/m),the freezing point of the solution is 4.43°C lower than that of pure camphor.Assuming vitamin K is a nonelectrolyte in camphor,calculate its molar mass.

Accepted Answer

A) 0.451 g/mol 
B) 55.4 g/mol 
C) 451 g/mol 
D) 3.54 × 104 g/mol 
A) 0.451 g/mol 
B) 55.4 g/mol 
C) 451 g/mol 
D) 3.54 × 104 g/mol

Question 17

Chloroform has a boiling point of 61.1°C and dichloromethane has a boiling point of 40.0°C.When 0.250 mol of dichloromethane is added to 0.750 mol of chloroform,the resulting solution will have a boiling point

Accepted Answer

A) between 40.0°C and 61.1°C,but closer to 61.1°C. 
B) between 40.0°C and 61.1°C,but closer to 40.0°C. 
C) greater than 61.1°C. 
D) less than 40.0°C. 
A) between 40.0°C and 61.1°C,but closer to 61.1°C. 
B) between 40.0°C and 61.1°C,but closer to 40.0°C. 
C) greater than 61.1°C. 
D) less than 40.0°C.

Question 18

Aqueous solutions of 30.0% (by weight)hydrogen peroxide,H2O2,are used to oxidize metals or organic molecules in chemical reactions.Calculate the molality of this solution.

Accepted Answer

A) 0.974 m 
B) 6.78 m 
C) 9.79 m 
D) 12.6 m 
A) 0.974 m 
B) 6.78 m 
C) 9.79 m 
D) 12.6 m

Exam 12: Solutions and Their Properties

Red blood cells are placed into pure water.Which of the following statements is true?

The average osmotic pressure of blood is about 7 atm.Therefore

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in ________ solvents,whereas nonpolar substances like I2 are more soluble in ________ solvents.

What is the mole fraction of I2 in a solution made by dissolving 27.8 g of I2 in 260 g of hexane,C6H14?

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water Kb = 0.51°C/m and Kf = 1.86°C/m.

An aqueous solution has a normal boiling point of 105.0°C.What is the freezing point of this solution? For water Kb is 0.51°C/m and Kf = 1.86°C/m.

What is the weight percent of vitamin C in a solution made by dissolving 8.00 g of vitamin C,C6H8O6,in 55.0 g of water?

What is the weight percent of vitamin C in a solution made by dissolving 1.30 g of vitamin C,C6H8O6,in 55.0 g of water?

A solution of 62.4 g of insulin in enough water to make 1.000 L of solution has an osmotic pressure of 0.305 atm at 25°C.Based on these data,what is the molar mass of insulin?

What is the freezing point of a solution of 8.00 g MgCl2 in 100 g of water? Kf for water is 1.86°C/m for water.

Assuming that sea water is a 3.5 wt % solution of NaCl in water,calculate its osmotic pressure at 20°C.The density of a 3.5% NaCl solution at 20°C is 1.023 g/mL.

The following diagram shows a close-up view of the vapor pressure curves for two pure liquids and two different solutions composed of these two liquids.Which curves represent pure liquids and which curves represent the solutions?

Drawing (1)shows a system in which an equilibrium exists between dissolved and undissolved gas particles at P = 1 atm.According to Henry's law,if the pressure is decreased to 0.5 atm and equilibrium is restored,which drawing (2)-(5)best represents the equilibrium at 0.5 atm?

A solution is 4.50% by weight NaHCO3.How many grams of NaHCO3 are in 450.0 g of solution?

Which of the following aqueous salt (NaCl)solutions has the greater concentration?

When 0.500 g of vitamin K is dissolved in 10.0 g of camphor (Kf = 40.0°C/m),the freezing point of the solution is 4.43°C lower than that of pure camphor.Assuming vitamin K is a nonelectrolyte in camphor,calculate its molar mass.

Chloroform has a boiling point of 61.1°C and dichloromethane has a boiling point of 40.0°C.When 0.250 mol of dichloromethane is added to 0.750 mol of chloroform,the resulting solution will have a boiling point

Aqueous solutions of 30.0% (by weight)hydrogen peroxide,H2O2,are used to oxidize metals or organic molecules in chemical reactions.Calculate the molality of this solution.

Chemical Tools: Experimentation and Measurement

Atoms, molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Periodicity and the Electronic Structure of Atoms

Ionic Compounds: Periodic Trends and Bonding

Covalent Bonding and Electron-Dot Structures

Covalent Compounds: Bonding Theories and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids, solids, and Phase Changes

Chemical Kinetics

Chemical Equilibrium

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Nuclear Chemistry

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

The Main-Group Elements

Connections to Organic and Biological Chemistry

Filters

According to the rule of thumb "like dissolves like" ionic solids like LiF or polar substances like glucose are more soluble in solvents,whereas nonpolar substances like I₂ are more soluble in solvents.

What is the mole fraction of I₂ in a solution made by dissolving 27.8 g of I₂ in 260 g of hexane,C₆H₁₄?

An aqueous solution has a normal boiling point of 102.5°C.What is the freezing point of this solution? For water K_b = 0.51°C/m and K_f = 1.86°C/m.

An aqueous solution has a normal boiling point of 105.0°C.What is the freezing point of this solution? For water K_b is 0.51°C/m and K_f = 1.86°C/m.

What is the weight percent of vitamin C in a solution made by dissolving 8.00 g of vitamin C,C₆H₈O₆,in 55.0 g of water?

What is the weight percent of vitamin C in a solution made by dissolving 1.30 g of vitamin C,C₆H₈O₆,in 55.0 g of water?

What is the freezing point of a solution of 8.00 g MgCl₂ in 100 g of water? K_f for water is 1.86°C/m for water.

A solution is 4.50% by weight NaHCO₃.How many grams of NaHCO₃ are in 450.0 g of solution?

When 0.500 g of vitamin K is dissolved in 10.0 g of camphor (K_f = 40.0°C/m),the freezing point of the solution is 4.43°C lower than that of pure camphor.Assuming vitamin K is a nonelectrolyte in camphor,calculate its molar mass.

Aqueous solutions of 30.0% (by weight)hydrogen peroxide,H₂O₂,are used to oxidize metals or organic molecules in chemical reactions.Calculate the molality of this solution.