Question 1

What is ?rG°?

Accepted Answer

A) 1338 kJ 
B) 918 kJ 
C) -130 kJ 
D) -918 kJ 
E) 130 kJ 
A) 1338 kJ 
B) 918 kJ 
C) -130 kJ 
D) -918 kJ 
E) 130 kJ

Question 2

For a reaction Keq = 1.2 × 10-6 at T = 200 K.What is ΔrG° for the reaction?

Accepted Answer

A) -22.7 kJ/mol 
B) 53.6 kJ/mol 
C) 22.7 kJ/mol 
D) -53.6 kJ/mol 
E) 170 kJ/mol 
A) -22.7 kJ/mol 
B) 53.6 kJ/mol 
C) 22.7 kJ/mol 
D) -53.6 kJ/mol 
E) 170 kJ/mol

Question 3

Consider the reaction:
 
What is ΔrG° for this reaction at 591 K? Is the reaction spontaneous at 591 K?

Accepted Answer

A) -196 kJ/mol,no 
B) 196 kJ/mol,yes 
C) 196 kJ/mol,no 
D) 239 kJ/mol,yes 
E) -239 kJ/mol,no 
A) -196 kJ/mol,no 
B) 196 kJ/mol,yes 
C) 196 kJ/mol,no 
D) 239 kJ/mol,yes 
E) -239 kJ/mol,no

Question 4

For the reaction,N2O4(g)→ 2 NO2(g)
S° (J/mol K)304.2 240.0
What is DrS°?

Accepted Answer

A) 544.2 J/mol ∙ K 
B) -64.2 J/mol ∙ K 
C) 175.8 J/mol ∙ K 
D) -175.8 J/mol ∙ K 
E) 64.2 J/mol ∙ K 
A) 544.2 J/mol ∙ K 
B) -64.2 J/mol ∙ K 
C) 175.8 J/mol ∙ K 
D) -175.8 J/mol ∙ K 
E) 64.2 J/mol ∙ K

Question 5

Consider the reaction:
N2(g)+ 3 X2(g)→ 2 NX3(g)
△fH° (kJ/mol)0.0 0.0 43
S° (J/(mol K))192 210 172
What is Keq for this reaction at 591 K?

Accepted Answer

A) 2.3 × 1017  
B) 4.3 × 10-18  
C) 1.04 
D) 0.96 
E) 132 
A) 2.3 × 1017  
B) 4.3 × 10-18  
C) 1.04 
D) 0.96 
E) 132

Question 6

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl4(l)at 35.0 °C to gaseous CCl4 at 76.8 °C (the normal boiling point for CCl4).The specific heat of CCl4(l)is 0.857 Jg-1°C-1 Its heat of fusion is   And its heat of vaporization is

Accepted Answer

A) 0.896 kJ 
B) 1.43 kJ 
C) 5.74 kJ 
D) 6.28 kJ 
A) 0.896 kJ 
B) 1.43 kJ 
C) 5.74 kJ 
D) 6.28 kJ

Question 7

Consider the following reaction.
 
What is ΔrG° for this reaction in kJ?

Accepted Answer

A) -804 
B) -476 
C) -386 
D) -413 
E) -799 
A) -804 
B) -476 
C) -386 
D) -413 
E) -799

Question 8

Consider the reaction of 25.0 mL of 0.20 M AgNO3(aq)with 25.0 mL of 0.20 M NaBr(aq)to form AgBr(s)at 25 °C.What is ΔG for this reaction? The Ksp of AgBr is 5.0 × 10-13 at 25 °C.

Accepted Answer

A) -58.8 kJ/mol 
B) -70.2 kJ/mol 
C) +58.8 kJ/mol 
D) +70.2 kJ/mol 
E) -28.3 kJ/mol 
A) -58.8 kJ/mol 
B) -70.2 kJ/mol 
C) +58.8 kJ/mol 
D) +70.2 kJ/mol 
E) -28.3 kJ/mol

Question 9

Which of the following quantities is practically independent of temperature?
I.ΔH
II.ΔS
III.ΔG

Accepted Answer

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

Question 10

Which of the following statements are true?
I.Liquids have more entropy than their solids.
II.Solutions have more entropy than the solids dissolved.
III.Gases and their liquids have equal entropy.
IV.Gases have less entropy than their solids.
V.Entropy of a substance increases as its temperature increases.

Accepted Answer

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

Question 11

Phosphorus and chlorine gases combine to produce phosphorus trichloride: 
  (g)+   (g)→   (g)
ΔrG° at 298 K for this reaction is -642.9 kJ mol-1.The value of ΔrG at 298 K for a reaction mixture that consists of     And   Is ________ kJ mol-1.

Accepted Answer

A) -44.2 
B) -3.88 ×   
C) -7.28 × 103 
D) -708.4 
E) -649.5 
A) -44.2 
B) -3.88 ×   
C) -7.28 × 103 
D) -708.4 
E) -649.5

Question 12

If the vapor pressure of water in an open system at 25 °C is 23.8 mmHg,what is ΔrG for the reaction below at 25 °C?
H2O(l)→ H2O(g,23.8 mmHg)

Accepted Answer

A) 0 kJ/mol 
B) -8.58 kJ/mol 
C) +8.58 kJ/mol 
D) -0.720 kJ/mol 
E) +0.720 kJ/mol 
A) 0 kJ/mol 
B) -8.58 kJ/mol 
C) +8.58 kJ/mol 
D) -0.720 kJ/mol 
E) +0.720 kJ/mol

Question 13

Ethyl chloride,C2H5Cl,is used as a local anesthetic.It works by cooling tissue as it vaporizes;its heat of vaporization is 26.4 kJ mol-1.How much heat could be removed by 20.0 g of ethyl chloride?

Accepted Answer

A) 8.19 kJ 
B) 341 kJ 
C) 528 kJ 
D) 3410 kJ 
A) 8.19 kJ 
B) 341 kJ 
C) 528 kJ 
D) 3410 kJ

Question 14

The value of ΔfG at 100.0 °C for the formation of calcium chloride from its constituent elements, Ca(s)+   (g)→   (s)
Is ________ kJ mol-1.At 25.0 °C for this reaction,ΔfH° is -795.8 kJ mol-1l,ΔfG ° is -748.1 kJ mol-1,and   Is

Accepted Answer

A) -855.4 
B) -736.2 
C) 5.88 ×   
D) -779.8 
E) 1.52 ×   
A) -855.4 
B) -736.2 
C) 5.88 ×   
D) -779.8 
E) 1.52 ×

Question 15

In a reversible reaction,a forward spontaneous reaction corresponds to a negative ΔG.

Accepted Answer

A) True 
 B)False

Question 16

Which one of the following would be expected to have the lowest standard molar entropy,S°,at 25 °C?

Accepted Answer

A) C10H22(s) 
B) C10H22(l) 
C) C14H30(s) 
D) C14     OH(l) 
A) C10H22(s) 
B) C10H22(l) 
C) C14H30(s) 
D) C14     OH(l)

Question 17

The fluorocarbon       Has a normal boiling point of 47.6 °C.The specific heats of   And       (g)are 0.91 J g-1 °C-1 and 0.67 J g-1 °C-1,respectively.The heat of vaporization of the compound is 27.49 kJ mol-1.The heat required to convert 50.0 g of the compound from the liquid at   To the gas at 80.0 °C is ________ kJ.

Accepted Answer

A) 8.19 
B) 1454 
C) 30.51 
D) 3031 
E) 10.36 
A) 8.19 
B) 1454 
C) 30.51 
D) 3031 
E) 10.36

Question 18

Which of the following relations is true for the molar entropy of sublimation of a substance?

Accepted Answer

A) ΔsubS = ΔfusS + ΔvapS 
B) ΔsubS vapS 
C) ΔsubS = ΔfusS - ΔvapS 
D) ΔsubS fusS + ΔvapS) 
E) ΔsubS > (ΔfusS + ΔvapS) 
A) ΔsubS = ΔfusS + ΔvapS 
B) ΔsubS vapS 
C) ΔsubS = ΔfusS - ΔvapS 
D) ΔsubS fusS + ΔvapS) 
E) ΔsubS > (ΔfusS + ΔvapS)

Question 19

An increase or a decrease in the number of microstates parallels an increase or
decrease in the number of microscopic particles and the space available to them.

Accepted Answer

A) True 
 B)False

Question 20

Predict whether ΔS is positive or negative for the following process:
H2O(g)→ H2O(s)

Accepted Answer

A) negative 
B) positive 
C) ΔS doesn't change. 
D) There is not enough information to determine. 
A) negative 
B) positive 
C) ΔS doesn't change. 
D) There is not enough information to determine.

Exam 13: Spontaneous Change: Entropy and Gibbs Energy

What is ?rG°?

For a reaction Keq = 1.2 × 10-6 at T = 200 K.What is ΔrG° for the reaction?

Consider the reaction: What is ΔrG° for this reaction at 591 K? Is the reaction spontaneous at 591 K?

For the reaction,N2O4(g)→ 2 NO2(g) S° (J/mol K)304.2 240.0 What is DrS°?

Consider the reaction: N2(g)+ 3 X2(g)→ 2 NX3(g) △fH° (kJ/mol)0.0 0.0 43 S° (J/(mol K))192 210 172 What is Keq for this reaction at 591 K?

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl4(l)at 35.0 °C to gaseous CCl4 at 76.8 °C (the normal boiling point for CCl4).The specific heat of CCl4(l)is 0.857 Jg-1°C-1 Its heat of fusion is And its heat of vaporization is

Consider the following reaction. What is ΔrG° for this reaction in kJ?

Consider the reaction of 25.0 mL of 0.20 M AgNO3(aq)with 25.0 mL of 0.20 M NaBr(aq)to form AgBr(s)at 25 °C.What is ΔG for this reaction? The Ksp of AgBr is 5.0 × 10-13 at 25 °C.

Which of the following quantities is practically independent of temperature? I.ΔH II.ΔS III.ΔG

Phosphorus and chlorine gases combine to produce phosphorus trichloride: (g)+ (g)→ (g) ΔrG° at 298 K for this reaction is -642.9 kJ mol-1.The value of ΔrG at 298 K for a reaction mixture that consists of And Is ________ kJ mol-1.

If the vapor pressure of water in an open system at 25 °C is 23.8 mmHg,what is ΔrG for the reaction below at 25 °C? H2O(l)→ H2O(g,23.8 mmHg)

Ethyl chloride,C2H5Cl,is used as a local anesthetic.It works by cooling tissue as it vaporizes;its heat of vaporization is 26.4 kJ mol-1.How much heat could be removed by 20.0 g of ethyl chloride?

The value of ΔfG at 100.0 °C for the formation of calcium chloride from its constituent elements, Ca(s)+ (g)→ (s) Is ________ kJ mol-1.At 25.0 °C for this reaction,ΔfH° is -795.8 kJ mol-1l,ΔfG ° is -748.1 kJ mol-1,and Is

In a reversible reaction,a forward spontaneous reaction corresponds to a negative ΔG.

Which one of the following would be expected to have the lowest standard molar entropy,S°,at 25 °C?

Which of the following relations is true for the molar entropy of sublimation of a substance?

An increase or a decrease in the number of microstates parallels an increase or decrease in the number of microscopic particles and the space available to them.

Predict whether ΔS is positive or negative for the following process: H2O(g)→ H2O(s)

Matter: Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Valence Bond and Molecular Orbital Theories

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acidbase Equilibria

Solubility and Complex-Ion Equilibria

Electrochemistry

Chemical Kinetics

Chemistry of the Main-Group Elements I: Groups 1,2,13,and 14

Chemistry of the Main-Group Elements Ii: Groups 18,17,16,15,and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

What is ?_rG°?

For a reaction K_eq = 1.2 × 10^-6 at T = 200 K.What is Δ_rG° for the reaction?

Consider the reaction: What is Δ_rG° for this reaction at 591 K? Is the reaction spontaneous at 591 K?

For the reaction,N₂O₄(g)→ 2 NO₂(g) S° (J/mol K)304.2 240.0 What is D_rS°?

Consider the reaction: N₂(g)+ 3 X₂(g)→ 2 NX₃(g) △_fH° (kJ/mol)0.0 0.0 43 S° (J/(mol K))192 210 172 What is K_eq for this reaction at 591 K?

Calculate the total quantity of heat required to convert 25.0 g of liquid CCl₄(l)at 35.0 °C to gaseous CCl₄ at 76.8 °C (the normal boiling point for CCl₄).The specific heat of CCl₄(l)is 0.857 Jg^-1°C^-1 Its heat of fusion is And its heat of vaporization is

Consider the following reaction. What is Δ_rG° for this reaction in kJ?

Consider the reaction of 25.0 mL of 0.20 M AgNO₃(aq)with 25.0 mL of 0.20 M NaBr(aq)to form AgBr(s)at 25 °C.What is ΔG for this reaction? The K_sp of AgBr is 5.0 × 10^-13 at 25 °C.

Phosphorus and chlorine gases combine to produce phosphorus trichloride: (g)+ (g)→ (g) Δ_rG° at 298 K for this reaction is -642.9 kJ mol^-1.The value of Δ_rG at 298 K for a reaction mixture that consists of And Is ________ kJ mol^-1.

If the vapor pressure of water in an open system at 25 °C is 23.8 mmHg,what is Δ_rG for the reaction below at 25 °C? H₂O(l)→ H₂O(g,23.8 mmHg)

Ethyl chloride,C₂H₅Cl,is used as a local anesthetic.It works by cooling tissue as it vaporizes;its heat of vaporization is 26.4 kJ mol^-1.How much heat could be removed by 20.0 g of ethyl chloride?

The value of Δ_fG at 100.0 °C for the formation of calcium chloride from its constituent elements, Ca(s)+ (g)→ (s) Is ________ kJ mol^-1.At 25.0 °C for this reaction,Δ_fH° is -795.8 kJ mol^-1l,Δ_fG ° is -748.1 kJ mol^-1,and Is

Predict whether ΔS is positive or negative for the following process: H₂O(g)→ H₂O(s)