Question 1

A solution is 2.25% by weight NaHCO3.How many grams of NaHCO3 are in 150.0 g of solution?

Accepted Answer

A) 1)50 g 
B) 3)38 g 
C) 66.7 g 
D) 225 g 
A) 1)50 g 
B) 3)38 g 
C) 66.7 g 
D) 225 g

Question 2

One reason ionic compounds do not dissolve well in nonpolar solvents is that

Accepted Answer

A) ion-dipole interactions are too large for effective solvation to occur. 
B) ion-solvent interactions are not strong enough to solvate the ions in solution. 
C) not all cations and anions have the same magnitude of charge and therefore do not form neutral ion pairs. 
D) there are no forces of attraction between ions and nonpolar molecules. 
A) ion-dipole interactions are too large for effective solvation to occur. 
B) ion-solvent interactions are not strong enough to solvate the ions in solution. 
C) not all cations and anions have the same magnitude of charge and therefore do not form neutral ion pairs. 
D) there are no forces of attraction between ions and nonpolar molecules.

Question 3

At 25 oC the vapor pressures of benzene and toluene are 96.0 mm Hg and 30.5 mm Hg,respectively.When a 1:1 molar mixture of benzene and toluene is fractionally distilled,the first fraction will have a mole fraction of benzene that is ________ (equal to,greater than,less than)0.50.

Accepted Answer

Question 4

-What is the approximate vapor composition above a boiling solution that is 0.70 XA and 0.30 XB?

Accepted Answer

A) 0)70 XA,0.30 XB 
B) 0)50 XA,0.50 XB 
C) 0)30 XA,0.70 XB 
D) 0 XA,1.00 XB 
A) 0)70 XA,0.30 XB 
B) 0)50 XA,0.50 XB 
C) 0)30 XA,0.70 XB 
D) 0 XA,1.00 XB

Question 5

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 6

Molarity is defined as ________,whereas molality is defined as ________.

Accepted Answer

moles of solute/lite

Question 7

How much water must be added to 42.0 g of CaCl2 to produce a solution that is 35.0 wt% CaCl2?

Accepted Answer

A) 56.7 g 
B) 78.0 g 
C) 83.3 g 
D) 120 g 
A) 56.7 g 
B) 78.0 g 
C) 83.3 g 
D) 120 g

Question 8

A solution is prepared by dissolving 17.75 g sulfuric acid,H2SO4,in enough water to make 100.0 mL of solution.If the density of the solution is 1.1094 g/mL,what is the molality?

Accepted Answer

A) 0)1775 m H2SO4 
B) 0)1810 m H2SO4 
C) 1)810 m H2SO4 
D) 1)940 m H2SO4 
A) 0)1775 m H2SO4 
B) 0)1810 m H2SO4 
C) 1)810 m H2SO4 
D) 1)940 m H2SO4

Question 9

At 80°C,pure liquid A has a vapor pressure of 700 mm Hg and pure liquid B has a vapor pressure of 940 mm Hg.What is XA for a solution of A and B with a normal boiling point of

Accepted Answer

A) 0)25 
B) 0)50 
C) 0)75 
D) A solution of A and B cannot boil at 80°C. 
A) 0)25 
B) 0)50 
C) 0)75 
D) A solution of A and B cannot boil at 80°C.

Question 10

Arrows in the energy diagram below represent enthalpy changes occurring in the endothermic formation of a solution:
ΔHS1U1B1solnS1U1B0 = enthalpy of solution
ΔHS1U1B1solute-soluteS1U1B0 = enthalpy change involving solute-solute interactions
ΔHS1U1B1solute-solventS1U1B0 = enthalpy change involving solute-solvent interactions
ΔHS1U1B1solvent-solventS1U1B0 = enthalpy change involving solvent-solvent interactions  
-Which arrow represents ΔHsoln?

Accepted Answer

A) arrow (a) 
B) arrow (b) 
C) arrow (c) 
D) arrow (d) 
A) arrow (a) 
B) arrow (b) 
C) arrow (c) 
D) arrow (d)

Question 11

Drawing (1)shows the equilibrium vapor pressure of a pure liquid.Which drawing (2)-(5)represents the equilibrium vapor pressure when a nonvolatile solute is dissolved in the liquid?

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 12

A 0.51 m aqueous solution of an unknown solute has a boiling point elevation of 0.62°C.The boiling point elevation of a 0.51 m solution of a nonionizing molecular solute in water is 0.26°C.How many moles of particles are formed per mole of solute when the unknown solute is dissolved in water?

Accepted Answer

A) 1)4 
B) 2)0 
C) 2)4 
D) 3)0 
A) 1)4 
B) 2)0 
C) 2)4 
D) 3)0

Question 13

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 14

Iodine,I2(s),is more soluble in dichloromethane,CH2Cl2(l),than in water because

Accepted Answer

A) both iodine and dichloromethane have strong ion-dipole interactions. 
B) the dipole-dipole forces in dichloromethane are much stronger than the dispersion forces in iodine. 
C) the intermolecular forces are similar in both iodine and dichloromethane. 
D) iodine is polar and dichloromethane has a large number of hydrogen bonds. 
A) both iodine and dichloromethane have strong ion-dipole interactions. 
B) the dipole-dipole forces in dichloromethane are much stronger than the dispersion forces in iodine. 
C) the intermolecular forces are similar in both iodine and dichloromethane. 
D) iodine is polar and dichloromethane has a large number of hydrogen bonds.

Question 15

A solution is prepared by dissolving 17.75 g sulfuric acid,H2SO4,in enough water to make 100.0 mL of solution.If the density of the solution is 1.1094 g/mL,what is the mole fraction H2SO4 in the solution?

Accepted Answer

A) 0)0181 
B) 0)0338 
C) 0)0350 
D) 19.0 
A) 0)0181 
B) 0)0338 
C) 0)0350 
D) 19.0

Question 16

At 20°C and 0.28 atm pressure Xenon has a solubility in water of 1.4 mmol/L.What is the Henry's Law-constant in mol/ L·atm at 20°C?

Accepted Answer

The answer of At 20°C and 0.28 atm pressure Xenon...

Question 17

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 18

What is the mole fraction of ethanol in a solution made by dissolving 14.6 g of ethanol,C2H5OH,in 53.6 g of water?

Accepted Answer

A) 0)0964 
B) 0)106 
C) 0)214 
D) 0)272 
A) 0)0964 
B) 0)106 
C) 0)214 
D) 0)272

Question 19

How many grams of sucrose,C12H22O11,must be added to 500.g of water at 100°C to change the vapor pressure to 752 mm Hg?

Accepted Answer

A) 0)295 g 
B) 5)32 g 
C) 10.6 g 
D) 101 g 
A) 0)295 g 
B) 5)32 g 
C) 10.6 g 
D) 101 g

Question 20

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

Exam 11: Solutions and Their Properties

A solution is 2.25% by weight NaHCO3.How many grams of NaHCO3 are in 150.0 g of solution?

One reason ionic compounds do not dissolve well in nonpolar solvents is that

At 25 oC the vapor pressures of benzene and toluene are 96.0 mm Hg and 30.5 mm Hg,respectively.When a 1:1 molar mixture of benzene and toluene is fractionally distilled,the first fraction will have a mole fraction of benzene that is ________ (equal to,greater than,less than)0.50.

-What is the approximate vapor composition above a boiling solution that is 0.70 XA and 0.30 XB?

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

Molarity is defined as ________,whereas molality is defined as ________.

How much water must be added to 42.0 g of CaCl2 to produce a solution that is 35.0 wt% CaCl2?

A solution is prepared by dissolving 17.75 g sulfuric acid,H2SO4,in enough water to make 100.0 mL of solution.If the density of the solution is 1.1094 g/mL,what is the molality?

At 80°C,pure liquid A has a vapor pressure of 700 mm Hg and pure liquid B has a vapor pressure of 940 mm Hg.What is XA for a solution of A and B with a normal boiling point of

Drawing (1)shows the equilibrium vapor pressure of a pure liquid.Which drawing (2)-(5)represents the equilibrium vapor pressure when a nonvolatile solute is dissolved in the liquid?

A 0.51 m aqueous solution of an unknown solute has a boiling point elevation of 0.62°C.The boiling point elevation of a 0.51 m solution of a nonionizing molecular solute in water is 0.26°C.How many moles of particles are formed per mole of solute when the unknown solute is dissolved in 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.

Iodine,I2(s),is more soluble in dichloromethane,CH2Cl2(l),than in water because

A solution is prepared by dissolving 17.75 g sulfuric acid,H2SO4,in enough water to make 100.0 mL of solution.If the density of the solution is 1.1094 g/mL,what is the mole fraction H2SO4 in the solution?

At 20°C and 0.28 atm pressure Xenon has a solubility in water of 1.4 mmol/L.What is the Henry's Law-constant in mol/ L·atm at 20°C?

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?

What is the mole fraction of ethanol in a solution made by dissolving 14.6 g of ethanol,C2H5OH,in 53.6 g of water?

How many grams of sucrose,C12H22O11,must be added to 500.g of water at 100°C to change the vapor pressure to 752 mm Hg?

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.

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds 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

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

Filters

A solution is 2.25% by weight NaHCO₃.How many grams of NaHCO₃ are in 150.0 g of solution?

At 25 ^oC the vapor pressures of benzene and toluene are 96.0 mm Hg and 30.5 mm Hg,respectively.When a 1:1 molar mixture of benzene and toluene is fractionally distilled,the first fraction will have a mole fraction of benzene that is ________ (equal to,greater than,less than)0.50.

-What is the approximate vapor composition above a boiling solution that is 0.70 X_A and 0.30 X_B?

Molarity is defined as ,whereas molality is defined as .

How much water must be added to 42.0 g of CaCl₂ to produce a solution that is 35.0 wt% CaCl₂?

A solution is prepared by dissolving 17.75 g sulfuric acid,H₂SO₄,in enough water to make 100.0 mL of solution.If the density of the solution is 1.1094 g/mL,what is the molality?

At 80°C,pure liquid A has a vapor pressure of 700 mm Hg and pure liquid B has a vapor pressure of 940 mm Hg.What is X_A for a solution of A and B with a normal boiling point of

Iodine,I₂(s),is more soluble in dichloromethane,CH₂Cl₂(l),than in water because

A solution is prepared by dissolving 17.75 g sulfuric acid,H₂SO₄,in enough water to make 100.0 mL of solution.If the density of the solution is 1.1094 g/mL,what is the mole fraction H₂SO₄ in the solution?

What is the mole fraction of ethanol in a solution made by dissolving 14.6 g of ethanol,C₂H₅OH,in 53.6 g of water?

How many grams of sucrose,C₁₂H₂₂O₁₁,must be added to 500.g of water at 100°C to change the vapor pressure to 752 mm Hg?

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.