Question 1

During a spontaneous chemical reaction, it is found that $\Delta$Ssys < 0. This means ________

Accepted Answer

A)  ($\Delta$surr sys.) 
B)  ($\Delta$Ssurr  $\Delta$Ssys.) 
C)  ($\Delta$Ssurr > 0 and its magnitude is sys.) 
D)  ($\Delta$Ssurr > 0 and its magnitude is > $\Delta$Ssys.) 
E)  an error has been made, because Ssys > 0 by necessity for a spontaneous process. 
A)  ($\Delta$surr sys.) 
B)  ($\Delta$Ssurr  $\Delta$Ssys.) 
C)  ($\Delta$Ssurr > 0 and its magnitude is sys.) 
D)  ($\Delta$Ssurr > 0 and its magnitude is > $\Delta$Ssys.) 
E)  an error has been made, because Ssys > 0 by necessity for a spontaneous process.

Question 2

Determine $\Delta$Grxn for C4H10(l) + $\frac { 13 } { 2 }$ O2(g) $\leftrightarrow$ 4CO2(g) + 5H2O(g) given the following information: $$\begin{array}{l}
\text { Substance }\
\begin{array} { c c c } 
&& \Delta G _ { \mathbf { f } } ^ { \circ } \
& & ( \mathbf { k J } / \mathbf { m o l } ) \
&& - 15.0 \
\mathrm { C } _ { 4 } \mathrm { H } _ { 10 } ( l ) & \
& \mathrm { CO } _ { 2 } ( g ) & - 394.4 \
& \mathrm { H } _ { 2 } \mathrm { O } ( g ) & - 228.57
\end{array}
\end{array}$$

Accepted Answer

A)  -2705 kJ 
B)  -608.0 kJ 
C)  -1,791 kJ 
D)  -3,457 kJ 
E)  +608.0 kJ 
A)  -2705 kJ 
B)  -608.0 kJ 
C)  -1,791 kJ 
D)  -3,457 kJ 
E)  +608.0 kJ

Question 3

The prediction of linearity in a van 't Hoff plot assumes ________

Accepted Answer

A)  that the reaction is run under ideal conditions. 
B)  that$\Delta$H$\degree$ and $\Delta$S$\degree$ are independent of temperature. 
C)  that $\Delta$G$\degree$ is independent of temperature. 
D)  that ln K is independent of temperature. 
E)  None of the above. 
A)  that the reaction is run under ideal conditions. 
B)  that$\Delta$H$\degree$ and $\Delta$S$\degree$ are independent of temperature. 
C)  that $\Delta$G$\degree$ is independent of temperature. 
D)  that ln K is independent of temperature. 
E)  None of the above.

Question 4

What is the value of the equilibrium constant at 500 K for a chemical equilibrium that has a $\Delta$H$\degree$ value of 250 kJ/mol and a$\Delta$S$\degree$value of 48 J/mol . K?

Accepted Answer

A)  4.22*1028 
B)  -3.01 * 104 
C)  -54.36 
D)  2.45 *10-24 
E)  7.58 
A)  4.22*1028 
B)  -3.01 * 104 
C)  -54.36 
D)  2.45 *10-24 
E)  7.58

Question 5

Suppose $\Delta$G° is 25.0 kJ/mol for a hypothetical reaction in which A converts into B. Under the reaction conditions, the free-energy change is larger, $\Delta$G = 30.0 kJ/mol. Which of the following statements describes this mixture of A and B?

Accepted Answer

A)  Only A is present. 
B)  Only B is present. 
C)  A and B have equal concentrations. 
D)  A is being converted into more B. 
E)  B is being converted back into A. 
A)  Only A is present. 
B)  Only B is present. 
C)  A and B have equal concentrations. 
D)  A is being converted into more B. 
E)  B is being converted back into A.

Question 6

Which of the following figures illustrates best the sequence of the free-energy values (shown with the star) for a chemical reaction at equilibrium to the removal of products, followed by the response of the equilibrium to this stress?

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 7

Which of the processes A-D will lead to a positive change in the entropy of the system? If all of these processes lead to a positive change in the entropy of the system, select E.

Accepted Answer

A)  Sodium chloride crystals form as saltwater evaporates. 
B)  Helium gas escapes from the hole in a balloon. 
C)  Stalactites form in a cave. 
D)  Water freezes in a freezer. 
E)  All of these lead to a positive change in entropy of the system, because they are all spontaneous. 
A)  Sodium chloride crystals form as saltwater evaporates. 
B)  Helium gas escapes from the hole in a balloon. 
C)  Stalactites form in a cave. 
D)  Water freezes in a freezer. 
E)  All of these lead to a positive change in entropy of the system, because they are all spontaneous.

Question 8

What is a microstate and how are microstates quantitatively related to entropy?

Accepted Answer

A microstate is a unique distr

Question 9

Which of the following processes are spontaneous?
I.Iron in the open air rusts.
II.Liquid water in a freezer turns to ice.
III.A spark ignites a mixture of propane and air.

Accepted Answer

A)  I only 
B)  I and II only 
C)  I and III only 
D)  II and III only 
E)  I, II, and III are all spontaneous. 
A)  I only 
B)  I and II only 
C)  I and III only 
D)  II and III only 
E)  I, II, and III are all spontaneous.

Question 10

What is the overall standard free-energy change for the following two reactions in terms of $\Delta$G1 and $\Delta$G2?
A + B $\rightarrow$ 2C $\Delta$G $\begin{array} { l } 
\circ\
\text { rxn }
\end{array}$ 
= $\Delta$G1
C + D $\rightarrow$ E $\Delta$G $\begin{array} { l } 
\circ\
\text { rxn }
\end{array}$ 
= $\Delta$G2

Accepted Answer

Because C is an inte

Question 11

Which of the following must be true for the microstates of a system?
I.The energy of each microstate equals the energy of the system.
II.The entropy of each microstate equals the entropy of the system.
III.The number of microstates equals the entropy of the system.

Accepted Answer

A)  I only 
B)  II only 
C)  III only 
D)  I and III only 
E)  I, II, and III are all true. 
A)  I only 
B)  II only 
C)  III only 
D)  I and III only 
E)  I, II, and III are all true.

Question 12

An ice cube at 0°C melts in a swimming pool at 20°C. What is the change in the entropy of the universe as a result? The ice cube was 1.00 inch on a side. Assume ice has a density of 0.917 g/cm3 and that the enthalpy of fusion of water is 6.01 kJ/mol.

Accepted Answer

A)  +1.3 J/K 
B)  -1.3 J/K 
C)  0.0 J/K 
D)  +18.4 J/K 
E)  +7.9 J/K 
A)  +1.3 J/K 
B)  -1.3 J/K 
C)  0.0 J/K 
D)  +18.4 J/K 
E)  +7.9 J/K

Question 13

Determine the change in the standard entropy of the universe for the given reaction from the given data.
H2(g) + $\frac { 1 } { 2 }$ 
O2(g) $\rightarrow$H2O(g) $ \begin{array}{ccr} 
Substance&&S^{\circ}(\mathbf{J} /(\mathbf{m o l} \cdot \mathbf{K}))\
&\Delta H_{\mathrm{f}}^{\circ}\
& (\mathbf{k J} / \mathbf{m o l}) & \ \mathrm{H}_{2}(g) & & 130.6 \ \mathrm{O}_{2}(g) & & 205.0 \ \mathrm{H}_{2} \mathrm{O}(g) & -241.8 & 188.7\end{array} $

Accepted Answer

Question 14

Which statement is true of the ideal gas constant, R, and the Boltzmann constant, kB?

Accepted Answer

A)  R/kB = Avogadro's number. 
B)  They both have units of J .mol-1 .K-1. 
C)  kBR = Avogadro's number. 
D)  kB/R = Avogadro's number. 
E)  8.3145 J is not equivalent to 0.082058 L . atm. 
A)  R/kB = Avogadro's number. 
B)  They both have units of J .mol-1 .K-1. 
C)  kBR = Avogadro's number. 
D)  kB/R = Avogadro's number. 
E)  8.3145 J is not equivalent to 0.082058 L . atm.

Question 15

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol-1. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

Accepted Answer

Question 16

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol-1. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

Accepted Answer

Question 17

A reaction is at equilibrium at a given temperature and constant pressure when ________

Accepted Answer

A)  ($\Delta$Srxn = 0.) 
B)  ($\Delta$S $\begin{array} { l } 
\circ\
\mathrm { rxn }
\end{array}$= 0) 
C)  ($\Delta$Grxn = 0.) 
D)  ($\Delta$G $\begin{array} { l } 
\circ\
\mathrm { rxn }
\end{array}$= 0)) 
E)  ($\Delta$Hrxn = 0.) 
A)  ($\Delta$Srxn = 0.) 
B)  ($\Delta$S $\begin{array} { l } 
\circ\
\mathrm { rxn }
\end{array}$= 0) 
C)  ($\Delta$Grxn = 0.) 
D)  ($\Delta$G $\begin{array} { l } 
\circ\
\mathrm { rxn }
\end{array}$= 0)) 
E)  ($\Delta$Hrxn = 0.)

Question 18

Which statement characterizes the following table?
Temperature Dependence of Reaction Spontaneity $$\begin{array} { | c | l | l | } 
\hline & { \Delta S  0 } \
\hline \Delta H  0 & \begin{array} { l } 
\text { Never spontaneous at any } \
\text { temperature. }
\end{array} & \begin{array} { l } 
\text { Spontaneous only at a sufficiently } \
\text { high temperature. }
\end{array} \
\hline
\end{array}$$

Accepted Answer

A)  All entries are correct. 
B)  All entries are incorrect. 
C)  One entry is incorrect. 
D)  Two entries are incorrect. 
E)  Three entries are incorrect. 
A)  All entries are correct. 
B)  All entries are incorrect. 
C)  One entry is incorrect. 
D)  Two entries are incorrect. 
E)  Three entries are incorrect.

Question 19

Which of the following graphs best depicts the entropy of a pure substance as the temperature is raised from its solid form through its liquid and gaseous forms?

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 20

Which statement characterizes the following table?
Temperature Dependence of Reaction Spontaneity $$\begin{array} { | c | l | l | } 
\hline &  { \Delta S  0 } \
\hline \Delta H  0 & \begin{array} { l } 
\text { Always spontaneous at any } \
\text { temperature. }
\end{array} & \begin{array} { l } 
\text { Spontaneous only at a sufficiently } \
\text { low temperature. }
\end{array} \
\hline
\end{array}$$

Accepted Answer

A)  All entries are correct. 
B)  All entries are incorrect. 
C)  One entry is incorrect. 
D)  Two entries are incorrect. 
E)  Three entries are incorrect. 
A)  All entries are correct. 
B)  All entries are incorrect. 
C)  One entry is incorrect. 
D)  Two entries are incorrect. 
E)  Three entries are incorrect.

During a spontaneous chemical reaction, it is found that $\Delta$ S_sys < 0. This means ________

Determine $\Delta$ G_rxn for C₄H₁₀(l) + $\frac { 13 } { 2 }$ O₂(g) $\leftrightarrow$ 4CO₂(g) + 5H₂O(g) given the following information: Substance \Delta (/) -15.0 (l) (g) -394.4 (g) -228.57

The prediction of linearity in a van 't Hoff plot assumes ________

What is the value of the equilibrium constant at 500 K for a chemical equilibrium that has a $\Delta$ H $\degree$ value of 250 kJ/mol and a $\Delta$ S $\degree$ value of 48 J/mol . K?

Suppose $\Delta$ G° is 25.0 kJ/mol for a hypothetical reaction in which A converts into B. Under the reaction conditions, the free-energy change is larger, $\Delta$ G = 30.0 kJ/mol. Which of the following statements describes this mixture of A and B?

Which of the following figures illustrates best the sequence of the free-energy values (shown with the star) for a chemical reaction at equilibrium to the removal of products, followed by the response of the equilibrium to this stress?

Which of the processes A-D will lead to a positive change in the entropy of the system? If all of these processes lead to a positive change in the entropy of the system, select E.

What is a microstate and how are microstates quantitatively related to entropy?

Which of the following processes are spontaneous? I.Iron in the open air rusts. II.Liquid water in a freezer turns to ice. III.A spark ignites a mixture of propane and air.

What is the overall standard free-energy change for the following two reactions in terms of $\Delta$ G₁and $\Delta$ G₂? A + B $\rightarrow$ 2C $\Delta$ G \circ rxn = $\Delta$ G₁ C + D $\rightarrow$ E $\Delta$ G \circ rxn = $\Delta$ G₂

Which of the following must be true for the microstates of a system? I.The energy of each microstate equals the energy of the system. II.The entropy of each microstate equals the entropy of the system. III.The number of microstates equals the entropy of the system.

An ice cube at 0°C melts in a swimming pool at 20°C. What is the change in the entropy of the universe as a result? The ice cube was 1.00 inch on a side. Assume ice has a density of 0.917 g/cm³ and that the enthalpy of fusion of water is 6.01 kJ/mol.

Determine the change in the standard entropy of the universe for the given reaction from the given data. H₂(g) + $\frac { 1 } { 2 }$ O₂(g) $\rightarrow$ H₂O(g) Substance (/(\cdot)) \Delta (/) (g) 130.6 (g) 205.0 (g) -241.8 188.7

Which statement is true of the ideal gas constant, R, and the Boltzmann constant, k_B?

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol^-¹. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol^-¹. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

A reaction is at equilibrium at a given temperature and constant pressure when ________

Which of the following graphs best depicts the entropy of a pure substance as the temperature is raised from its solid form through its liquid and gaseous forms?

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

Solutions: Properties and Behavior

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

Electrochemistry: the Quest for Clean Energy

Biochemistry: the Compounds of Life

Nuclear Chemistry: Applications to Energy and Medicine

Life and the Periodic Table

Filters

Exam 18: Thermodynamics: Spontaneous and Nonspontaneous Reactions and Processes

During a spontaneous chemical reaction, it is found that Δ\DeltaΔ Ssys < 0. This means ________

Determine Δ\DeltaΔ Grxn for C4H10(l) + 132\frac { 13 } { 2 }213​ O2(g) ↔\leftrightarrow↔ 4CO2(g) + 5H2O(g) given the following information: Substance \Delta (/) -15.0 (l) (g) -394.4 (g) -228.57

The prediction of linearity in a van 't Hoff plot assumes ________

What is the value of the equilibrium constant at 500 K for a chemical equilibrium that has a Δ\DeltaΔ H °\degree° value of 250 kJ/mol and a Δ\DeltaΔ S °\degree° value of 48 J/mol . K?

Suppose Δ\DeltaΔ G° is 25.0 kJ/mol for a hypothetical reaction in which A converts into B. Under the reaction conditions, the free-energy change is larger, Δ\DeltaΔ G = 30.0 kJ/mol. Which of the following statements describes this mixture of A and B?

Which of the following figures illustrates best the sequence of the free-energy values (shown with the star) for a chemical reaction at equilibrium to the removal of products, followed by the response of the equilibrium to this stress?

Which of the processes A-D will lead to a positive change in the entropy of the system? If all of these processes lead to a positive change in the entropy of the system, select E.

What is a microstate and how are microstates quantitatively related to entropy?

Which of the following processes are spontaneous? I.Iron in the open air rusts. II.Liquid water in a freezer turns to ice. III.A spark ignites a mixture of propane and air.

What is the overall standard free-energy change for the following two reactions in terms of Δ\DeltaΔ G1 and Δ\DeltaΔ G2? A + B →\rightarrow→ 2C Δ\DeltaΔ G \circ rxn = Δ\DeltaΔ G1 C + D →\rightarrow→ E Δ\DeltaΔ G \circ rxn = Δ\DeltaΔ G2

Which of the following must be true for the microstates of a system? I.The energy of each microstate equals the energy of the system. II.The entropy of each microstate equals the entropy of the system. III.The number of microstates equals the entropy of the system.

An ice cube at 0°C melts in a swimming pool at 20°C. What is the change in the entropy of the universe as a result? The ice cube was 1.00 inch on a side. Assume ice has a density of 0.917 g/cm3 and that the enthalpy of fusion of water is 6.01 kJ/mol.

Determine the change in the standard entropy of the universe for the given reaction from the given data. H2(g) + 12\frac { 1 } { 2 }21​ O2(g) →\rightarrow→ H2O(g) Substance (/(\cdot)) \Delta (/) (g) 130.6 (g) 205.0 (g) -241.8 188.7

Which statement is true of the ideal gas constant, R, and the Boltzmann constant, kB?

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol-1. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol-1. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

A reaction is at equilibrium at a given temperature and constant pressure when ________

Which of the following graphs best depicts the entropy of a pure substance as the temperature is raised from its solid form through its liquid and gaseous forms?

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

Solutions: Properties and Behavior

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

Electrochemistry: the Quest for Clean Energy

Biochemistry: the Compounds of Life

Nuclear Chemistry: Applications to Energy and Medicine

Life and the Periodic Table

Filters

During a spontaneous chemical reaction, it is found that $\Delta$ S_sys < 0. This means ________

Determine $\Delta$ G_rxn for C₄H₁₀(l) + $\frac { 13 } { 2 }$ O₂(g) $\leftrightarrow$ 4CO₂(g) + 5H₂O(g) given the following information: Substance \Delta (/) -15.0 (l) (g) -394.4 (g) -228.57

What is the value of the equilibrium constant at 500 K for a chemical equilibrium that has a $\Delta$ H $\degree$ value of 250 kJ/mol and a $\Delta$ S $\degree$ value of 48 J/mol . K?

Suppose $\Delta$ G° is 25.0 kJ/mol for a hypothetical reaction in which A converts into B. Under the reaction conditions, the free-energy change is larger, $\Delta$ G = 30.0 kJ/mol. Which of the following statements describes this mixture of A and B?

What is the overall standard free-energy change for the following two reactions in terms of $\Delta$ G₁and $\Delta$ G₂? A + B $\rightarrow$ 2C $\Delta$ G \circ rxn = $\Delta$ G₁ C + D $\rightarrow$ E $\Delta$ G \circ rxn = $\Delta$ G₂

An ice cube at 0°C melts in a swimming pool at 20°C. What is the change in the entropy of the universe as a result? The ice cube was 1.00 inch on a side. Assume ice has a density of 0.917 g/cm³ and that the enthalpy of fusion of water is 6.01 kJ/mol.

Determine the change in the standard entropy of the universe for the given reaction from the given data. H₂(g) + $\frac { 1 } { 2 }$ O₂(g) $\rightarrow$ H₂O(g) Substance (/(\cdot)) \Delta (/) (g) 130.6 (g) 205.0 (g) -241.8 188.7

Which statement is true of the ideal gas constant, R, and the Boltzmann constant, k_B?

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol^-¹. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.

The standard molar enthalpy of fusion for xenon is 2.30 kJ mol^-¹. Calculate the standard molar entropy for the freezing of liquid xenon given that its normal freezing point is -112°C.