Question 1

Determine the molarity of an aspirin solution that produces an osmotic pressure of 0.0555 atm at 25°C (i = 1).

Accepted Answer

The answer of Determine the molarity of an aspirin solution...

Question 2

Which one of the ionic compounds below would you expect to have the largest (most negative) lattice energy?

Accepted Answer

A)  MgF2 
B)  MgCl2 
C)  MgBr2 
D)  MgI2 
E)  CaI2 
A)  MgF2 
B)  MgCl2 
C)  MgBr2 
D)  MgI2 
E)  CaI2

Question 3

A 15.0 mg sample of a protein was dissolved in water to produce 5.00 mL of solution at 25.1°C. The osmotic pressure of this solution was measured and found to be 6.50 torr. What is the molar mass of this protein?

Accepted Answer

A)  427 g/mol 
B)  941 g/mol 
C)  8,580 g/mol 
D)  4,270 g/mol 
E)  561 g/mol 
A)  427 g/mol 
B)  941 g/mol 
C)  8,580 g/mol 
D)  4,270 g/mol 
E)  561 g/mol

Question 4

What would be the freezing point of a 1 m solution of HCl in water (Kf = 1.86°C)?

Accepted Answer

A)  0.0°C 
B)  -1.86°C 
C)  -3.72°C 
D)  1.86°C 
E)  -0.93°C 
A)  0.0°C 
B)  -1.86°C 
C)  -3.72°C 
D)  1.86°C 
E)  -0.93°C

Question 5

The term colligative refers to properties that ________

Accepted Answer

depend on the number of partic

Question 6

Which statement A-D about ionic solids is not correct?

Accepted Answer

A)  The enthalpy of hydration includes two terms: one for ion-dipole interactions and one for dipole-dipole interactions. 
B)  The melting point of an ionic solid increases as the lattice energy increases. 
C)  The enthalpy of solution consists of three terms: one for the lattice energy, one for ion-dipole interactions, and one for dipole-dipole interactions. 
D)  The lattice energy depends inversely on the product of ionic charges, directly on the distance between the ions, and on the structure of the solid. 
E)  Statements A-D are all correct. 
A)  The enthalpy of hydration includes two terms: one for ion-dipole interactions and one for dipole-dipole interactions. 
B)  The melting point of an ionic solid increases as the lattice energy increases. 
C)  The enthalpy of solution consists of three terms: one for the lattice energy, one for ion-dipole interactions, and one for dipole-dipole interactions. 
D)  The lattice energy depends inversely on the product of ionic charges, directly on the distance between the ions, and on the structure of the solid. 
E)  Statements A-D are all correct.

Question 7

In the diagram below, one beaker contains pure water and the other contains an equal volume of seawater. Seawater has various salts dissolved in it. The beakers are sitting in a totally enclosed chamber, and the outside temperature and pressure are held constant. Identify the statements below about this situation that are not correct.   I. Water will be transferred from the pure water beaker to the seawater beaker.
II) The vapor pressure of the seawater is higher than the vapor pressure of the pure water.
III) Pure water evaporates at a faster rate than seawater.
IV) Water in the gas phase condenses into the seawater beaker at a faster rate than into the pure water beaker.

Accepted Answer

A)  I, III, and IV 
B)  II, III, and IV 
C)  II and III 
D)  II and IV 
E)  II only 
A)  I, III, and IV 
B)  II, III, and IV 
C)  II and III 
D)  II and IV 
E)  II only

Question 8

The solubility of any gas in a liquid can always be increased by ________

Accepted Answer

A)  increasing the temperature. 
B)  using a solvent that can form hydrogen bonds. 
C)  using a solvent that is nonpolar. 
D)  decreasing the pressure of the gas above the solvent. 
E)  increasing the pressure of the gas above the solvent. 
A)  increasing the temperature. 
B)  using a solvent that can form hydrogen bonds. 
C)  using a solvent that is nonpolar. 
D)  decreasing the pressure of the gas above the solvent. 
E)  increasing the pressure of the gas above the solvent.

Question 9

Which statement A-D about ionic solids is not correct?

Accepted Answer

A)  The enthalpy of hydration includes two terms: one for ion-dipole interactions and one for dipole-dipole interactions. 
B)  The melting point of an ionic solid increases as the lattice energy increases. 
C)  The enthalpy of solution consists of two terms: the lattice energy and the enthalpy of hydration. 
D)  The lattice energy depends directly on the product of ionic charges, inversely on the distance between the ions, and on the structure of the solid. 
E)  Statements A-D are all correct. 
A)  The enthalpy of hydration includes two terms: one for ion-dipole interactions and one for dipole-dipole interactions. 
B)  The melting point of an ionic solid increases as the lattice energy increases. 
C)  The enthalpy of solution consists of two terms: the lattice energy and the enthalpy of hydration. 
D)  The lattice energy depends directly on the product of ionic charges, inversely on the distance between the ions, and on the structure of the solid. 
E)  Statements A-D are all correct.

Question 10

Which solution, if either, would create the higher osmotic pressure (compared to pure water): one prepared from 1.0 g of NaCl in 10 mL of water or 1.0 g of CsBr in 10 mL of water?

Accepted Answer

A)  They would have the same osmotic pressures. 
B)  NaCl would give the higher pressure. 
C)  CsBr would give the higher pressure. 
D)  It is impossible to tell. 
E)  These compounds are salts and do not produce an osmotic pressure. 
A)  They would have the same osmotic pressures. 
B)  NaCl would give the higher pressure. 
C)  CsBr would give the higher pressure. 
D)  It is impossible to tell. 
E)  These compounds are salts and do not produce an osmotic pressure.

Question 11

Use the following data to calculate the lattice energy of lithium oxide, Li2O. $$\begin{array} { l c } 
{ \text { Quantity } } & \text { Magnitude } ( \mathrm { kJ } / \mathbf { m o l } ) \
\text { Ionization energy of } \mathrm { Li } ( g ) & 519 \
\text { Electron affinity of } \mathrm { O } ( g ) \text { for } 2 \mathrm { e } & 603 \
\text { Vaporization energy of } \mathrm { Li } ( s ) & 147 \
\text { Bond energy of } \mathrm { O } _ { 2 } ( g ) & 499 \
\text { Reaction enthalpy: } 2 \mathrm { Li } ( s ) + \frac { 1 } { 2 } \mathrm { O } _ { 2 } ( g ) \rightarrow \mathrm { Li } _ { 2 } \mathrm { O } ( s ) & - 20
\end{array}$$

Accepted Answer

A)  -2,586 kJ/mol 
B)  -2,972 kJ/mol 
C)  -3,081 kJ/mol 
D)  -2,205 kJ/mol 
E)  -2,831 kJ/mol 
A)  -2,586 kJ/mol 
B)  -2,972 kJ/mol 
C)  -3,081 kJ/mol 
D)  -2,205 kJ/mol 
E)  -2,831 kJ/mol

Question 12

Ethylene glycol is used commonly as an antifreeze in automobile radiators. Automobile temperatures in the U.S. are commonly measured in degrees Fahrenheit. A 50:50 mixture of ethylene glycol and water by volume protects down to about -30°F. What is the boiling point in °F of this 50:50 mixture? (C2H6O2, 62.07 g/mol, 1.1132 g/mL, Kb = 0.94°F/m).

Accepted Answer

Question 13

Which of the following requires the smallest energy to separate the ions?

Accepted Answer

A)  CaF2 
B)  KF 
C)  NaF 
D)  MgF2 
E)  LiF 
A)  CaF2 
B)  KF 
C)  NaF 
D)  MgF2 
E)  LiF

Question 14

A bottle is half-filled with a mixture of 25% liquid heptane and 75% liquid octane (mole fractions) at 25°C. What is the mole ratio of heptane to octane in the space above the liquid compared to in the liquid? The vapor pressures are 31 torr for pure heptane and 11 torr for pure octane.

Accepted Answer

mole ratio heptane/o

Question 15

A newspaper article suggested using a fertilizer such as ammonium sulfate or ammonium nitrate to lower the melting point of ice on sidewalks because many of the deicing salts can damage lawns and sidewalks. Which of the following compounds would give the largest freezing point depression when 100 g of the compound are dissolved in 1 kg of solvent?

Accepted Answer

A)  NH4NO3 (80.1 g/mol) 
B)  (NH4)2SO4 (132.1 g/mol) 
C)  MgSO4 (120.4 g/mol) 
D)  CaCl2 (111.0 g/mol) 
E)  MgCl2 (95.2 g/mol) 
A)  NH4NO3 (80.1 g/mol) 
B)  (NH4)2SO4 (132.1 g/mol) 
C)  MgSO4 (120.4 g/mol) 
D)  CaCl2 (111.0 g/mol) 
E)  MgCl2 (95.2 g/mol)

Question 16

Henry's law constant (mol/L · atm) for oxygen dissolving in blood is 3.74 *10-2 mol/L · atm at body temperature, 37°C. Calculate the molar concentration of oxygen in blood for an alpine climber where the atmospheric pressure is 0.45 atm. The mole fraction of oxygen in air is 0.209.

Accepted Answer

A)  7.8 *10-3 M 
B)  3.5 *10-3 M 
C)  2.3 *10-2 M 
D)  1.3 *10-2 M 
E)  0.11 M 
A)  7.8 *10-3 M 
B)  3.5 *10-3 M 
C)  2.3 *10-2 M 
D)  1.3 *10-2 M 
E)  0.11 M

Question 17

Describe how the data obtained by a measurement of osmotic pressure can be used to determine the molar mass of a compound.

Accepted Answer

The concentration (molarity) of particle

Question 18

Isopropyl alcohol has a boiling point of 82.3°C. Solutions of isopropyl alcohol in water have normal boiling points less than 100°C. Is this observation consistent with the following equation? Explain.
$\Delta$Tb = iKbm

Accepted Answer

A)  No, boiling point elevation only pertains to ionic solutes. 
B)  No, boiling point elevation only pertains to nonvolatile solutes. 
C)  Yes, boiling point depression occurs for all solutions. 
D)  Yes, the boiling point depression constant for isopropyl alcohol is large. 
E)  No, isopropyl alcohol can hydrogen bond with water. 
A)  No, boiling point elevation only pertains to ionic solutes. 
B)  No, boiling point elevation only pertains to nonvolatile solutes. 
C)  Yes, boiling point depression occurs for all solutions. 
D)  Yes, the boiling point depression constant for isopropyl alcohol is large. 
E)  No, isopropyl alcohol can hydrogen bond with water.

Question 19

The normal temperature range of the liquid phase of pure water is 0°C to 100°C. Which of the following solutions will have the largest temperature range for the liquid state?

Accepted Answer

A)  1 M aqueous ethanol solution 
B)  1 M aqueous potassium bromide solution 
C)  1 M aqueous acetic acid solution 
D)  1 M aqueous magnesium bromide solution 
E)  1 M aqueous magnesium sulfate 
A)  1 M aqueous ethanol solution 
B)  1 M aqueous potassium bromide solution 
C)  1 M aqueous acetic acid solution 
D)  1 M aqueous magnesium bromide solution 
E)  1 M aqueous magnesium sulfate

Question 20

In the process of dialysis, a special semipermeable membrane allows both small molecules and water to pass through, but not large protein molecules. These membranes are used to separate these small molecules and ions from much larger proteins. If a mixture of proteins and small molecules were separated from pure water by a dialysis membrane as shown in the figure, which way would the molecules flow?

Accepted Answer

A)  Both water and small molecules would pass through into the pure water. 
B)  Only the proteins would pass through into the pure water. 
C)  Water would enter the solution while small molecules would pass through into the pure water. 
D)  Only small molecules would pass through the membrane; water and proteins would not. 
E)  Only water would pass through the membrane into the solution. 
A)  Both water and small molecules would pass through into the pure water. 
B)  Only the proteins would pass through into the pure water. 
C)  Water would enter the solution while small molecules would pass through into the pure water. 
D)  Only small molecules would pass through the membrane; water and proteins would not. 
E)  Only water would pass through the membrane into the solution.

Determine the molarity of an aspirin solution that produces an osmotic pressure of 0.0555 atm at 25°C (i = 1).

Which one of the ionic compounds below would you expect to have the largest (most negative) lattice energy?

A 15.0 mg sample of a protein was dissolved in water to produce 5.00 mL of solution at 25.1°C. The osmotic pressure of this solution was measured and found to be 6.50 torr. What is the molar mass of this protein?

What would be the freezing point of a 1 m solution of HCl in water (K_f= 1.86°C)?

The term colligative refers to properties that ________

Which statement A-D about ionic solids is not correct?

The solubility of any gas in a liquid can always be increased by ________

Which statement A-D about ionic solids is not correct?

Which solution, if either, would create the higher osmotic pressure (compared to pure water): one prepared from 1.0 g of NaCl in 10 mL of water or 1.0 g of CsBr in 10 mL of water?

Use the following data to calculate the lattice energy of lithium oxide, Li₂O. Quantity Magnitude (/) Ionization energy of (g) 519 Electron affinity of (g) for 2 603 Vaporization energy of (s) 147 Bond energy of (g) 499 Reaction enthalpy: 2(s)+(g)\rightarrow(s) -20

Which of the following requires the smallest energy to separate the ions?

A bottle is half-filled with a mixture of 25% liquid heptane and 75% liquid octane (mole fractions) at 25°C. What is the mole ratio of heptane to octane in the space above the liquid compared to in the liquid? The vapor pressures are 31 torr for pure heptane and 11 torr for pure octane.

Henry's law constant (mol/L · atm) for oxygen dissolving in blood is 3.74 *10^-² mol/L · atm at body temperature, 37°C. Calculate the molar concentration of oxygen in blood for an alpine climber where the atmospheric pressure is 0.45 atm. The mole fraction of oxygen in air is 0.209.

Describe how the data obtained by a measurement of osmotic pressure can be used to determine the molar mass of a compound.

Isopropyl alcohol has a boiling point of 82.3°C. Solutions of isopropyl alcohol in water have normal boiling points less than 100°C. Is this observation consistent with the following equation? Explain. $\Delta$ T_b = iK_bm

The normal temperature range of the liquid phase of pure water is 0°C to 100°C. Which of the following solutions will have the largest temperature range for the liquid state?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Stoichiometry: Mass, Formulas, and Reactions

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: the Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Chemical Bonds: What Makes a Gas a Greenhouse Gas

Molecular Geometry: Shape Determines Function

Intermolecular Forces: The Uniqueness of Water

Solids: Structures and Applications

Organic Chemistry: Fuels, Pharmaceuticals, Materials, and Life

Chemical Kinetics: Reactions in the Air We Breathe

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acid-Base and Solubility Equilibria: Reactions in Soil and Water

Metal Ions: Colorful and Essential

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Electrochemistry: the Quest for Clean Energy

Biochemistry: the Compounds of Life

Nuclear Chemistry: Applications to Energy and Medicine

Life and the Periodic Table

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Exam 11: Solutions: Properties and Behavior

Determine the molarity of an aspirin solution that produces an osmotic pressure of 0.0555 atm at 25°C (i = 1).

Which one of the ionic compounds below would you expect to have the largest (most negative) lattice energy?

A 15.0 mg sample of a protein was dissolved in water to produce 5.00 mL of solution at 25.1°C. The osmotic pressure of this solution was measured and found to be 6.50 torr. What is the molar mass of this protein?

What would be the freezing point of a 1 m solution of HCl in water (Kf = 1.86°C)?

The term colligative refers to properties that ________

Which statement A-D about ionic solids is not correct?

The solubility of any gas in a liquid can always be increased by ________

Which statement A-D about ionic solids is not correct?

Which solution, if either, would create the higher osmotic pressure (compared to pure water): one prepared from 1.0 g of NaCl in 10 mL of water or 1.0 g of CsBr in 10 mL of water?

Use the following data to calculate the lattice energy of lithium oxide, Li2O. Quantity Magnitude (/) Ionization energy of (g) 519 Electron affinity of (g) for 2 603 Vaporization energy of (s) 147 Bond energy of (g) 499 Reaction enthalpy: 2(s)+(g)\rightarrow(s) -20

Which of the following requires the smallest energy to separate the ions?

A bottle is half-filled with a mixture of 25% liquid heptane and 75% liquid octane (mole fractions) at 25°C. What is the mole ratio of heptane to octane in the space above the liquid compared to in the liquid? The vapor pressures are 31 torr for pure heptane and 11 torr for pure octane.

Henry's law constant (mol/L · atm) for oxygen dissolving in blood is 3.74 *10-2 mol/L · atm at body temperature, 37°C. Calculate the molar concentration of oxygen in blood for an alpine climber where the atmospheric pressure is 0.45 atm. The mole fraction of oxygen in air is 0.209.

Describe how the data obtained by a measurement of osmotic pressure can be used to determine the molar mass of a compound.

Isopropyl alcohol has a boiling point of 82.3°C. Solutions of isopropyl alcohol in water have normal boiling points less than 100°C. Is this observation consistent with the following equation? Explain. Δ\DeltaΔ Tb = iKbm

The normal temperature range of the liquid phase of pure water is 0°C to 100°C. Which of the following solutions will have the largest temperature range for the liquid state?

Matter and Energy: The Origin of the Universe

Atoms, Ions, and Molecules: Matter Starts Here

Stoichiometry: Mass, Formulas, and Reactions

Solution Chemistry: The Hydrosphere

Thermochemistry: Energy Changes in Reactions

Properties of Gases: the Air We Breathe

A Quantum Model of Atoms: Waves and Particles

Chemical Bonds: What Makes a Gas a Greenhouse Gas

Molecular Geometry: Shape Determines Function

Intermolecular Forces: The Uniqueness of Water

Solids: Structures and Applications

Organic Chemistry: Fuels, Pharmaceuticals, Materials, and Life

Chemical Kinetics: Reactions in the Air We Breathe

Chemical Equilibrium: How Much Product Does a Reaction Really Make

Acid-Base and Solubility Equilibria: Reactions in Soil and Water

Metal Ions: Colorful and Essential

Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

Electrochemistry: the Quest for Clean Energy

Biochemistry: the Compounds of Life

Nuclear Chemistry: Applications to Energy and Medicine

Life and the Periodic Table

Filters

What would be the freezing point of a 1 m solution of HCl in water (K_f= 1.86°C)?

Use the following data to calculate the lattice energy of lithium oxide, Li₂O. Quantity Magnitude (/) Ionization energy of (g) 519 Electron affinity of (g) for 2 603 Vaporization energy of (s) 147 Bond energy of (g) 499 Reaction enthalpy: 2(s)+(g)\rightarrow(s) -20

Henry's law constant (mol/L · atm) for oxygen dissolving in blood is 3.74 *10^-² mol/L · atm at body temperature, 37°C. Calculate the molar concentration of oxygen in blood for an alpine climber where the atmospheric pressure is 0.45 atm. The mole fraction of oxygen in air is 0.209.

Isopropyl alcohol has a boiling point of 82.3°C. Solutions of isopropyl alcohol in water have normal boiling points less than 100°C. Is this observation consistent with the following equation? Explain. $\Delta$ T_b = iK_bm