Question 1

The value of ΔS° for the decomposition of calcium chloride into its constituent elements, CaCl2 (s)→ Ca (s)+ Cl2 (g)
Is ________ J/K ∙ mol.

Accepted Answer

A) -104.6 
B) +104.6 
C) +369.0 
D) -159.8 
E) +159.8 
A) -104.6 
B) +104.6 
C) +369.0 
D) -159.8 
E) +159.8

Question 2

A reversible process is one that ________.

Accepted Answer

A) can be reversed with no net change in either system or surroundings 
B) happens spontaneously 
C) is spontaneous in both directions 
D) must be carried out at low temperature 
E) must be carried out at high temperature 
A) can be reversed with no net change in either system or surroundings 
B) happens spontaneously 
C) is spontaneous in both directions 
D) must be carried out at low temperature 
E) must be carried out at high temperature

Question 3

The normal boiling point of water is 100.0 °C and its molar enthalpy of vaporization is 40.67 kJ/mol.What is the change in entropy in the system in J/K when 24.7 grams of steam at 1 atm condenses to a liquid at the normal boiling point?

Accepted Answer

A) 88.8 
B) -88.8 
C) -150 
D) 373 
E) -40.7 
A) 88.8 
B) -88.8 
C) -150 
D) 373 
E) -40.7

Question 4

The value of ΔH° for the formation of POCl3 from its constituent elements, P2 (g)+ O2 (g)+ 3Cl2 (g)→ 2POCl3 (g)
Is ________ kJ/mol.

Accepted Answer

A) -1228.7 
B) -397.7 
C) -686.5 
D) +1228.7 
E) +686.5 
A) -1228.7 
B) -397.7 
C) -686.5 
D) +1228.7 
E) +686.5

Question 5

ΔS is positive for the reaction ________.

Accepted Answer

A) Pb(NO3)2 (aq)+ 2KI(aq)→ PbI2 (s)+ 2KNO3 (aq) 
B) 2H2O (g)→ 2H2 (g)+ O2 (g) 
C) H2O (g)→ H2O (s) 
D) NO (g)+ O2 (g)→ NO2 (g) 
E) Ag+ (aq)+ Cl- (aq)→ AgCl (s) 
A) Pb(NO3)2 (aq)+ 2KI(aq)→ PbI2 (s)+ 2KNO3 (aq) 
B) 2H2O (g)→ 2H2 (g)+ O2 (g) 
C) H2O (g)→ H2O (s) 
D) NO (g)+ O2 (g)→ NO2 (g) 
E) Ag+ (aq)+ Cl- (aq)→ AgCl (s)

Question 6

What is the equilibrium constant for a reaction at 25 °C.The value of ΔG° is -57.5 kJ/mol.

Accepted Answer

A) 8.4 × 10101 
B) 10 
C) 1.0 
D) 1.2 × 1010 
E) more information is needed 
A) 8.4 × 10101 
B) 10 
C) 1.0 
D) 1.2 × 1010 
E) more information is needed

Question 7

The value of ΔH° for the decomposition of POCl3 into its constituent elements, 2POCl3 (g)→ P2 (g)+ O2 (g)+ 3Cl2 (g)
Is ________ kJ/mol.

Accepted Answer

A) -1228.7 
B) +1228.7 
C) -940.1 
D) +940.1 
E) 0.00 
A) -1228.7 
B) +1228.7 
C) -940.1 
D) +940.1 
E) 0.00

Question 8

Which of the following has the largest entropy?

Accepted Answer

A) HI (g) 
B) HBr (g) 
C) HCl (g) 
D) HCl (s) 
E) HCl (l) 
A) HI (g) 
B) HBr (g) 
C) HCl (g) 
D) HCl (s) 
E) HCl (l)

Question 9

At what temperature (in K)will a reaction become spontaneous?
 ΔH is 115.0 kJ/mol and ΔS is 75.00 J/K ∙ mol.

Accepted Answer

The answer of At what temperature (in K)will a reaction...

Question 10

The value of ΔG° at 25 °C for the decomposition of POCl3 into its constituent elements, 2POCl3 (g)→ P2 (g)+ O2 (g)+ 3Cl2 (g)
Is ________ kJ/mol.

Accepted Answer

A) -1108.7 
B) +1108.7 
C) -606.2 
D) +606.2 
E) -1,005 
A) -1108.7 
B) +1108.7 
C) -606.2 
D) +606.2 
E) -1,005

Question 11

The value of ΔG° for a reaction conducted at 25 °C is 3.05 kJ/mol.The equilibrium constant for a reaction is ________ at this temperature.

Accepted Answer

A) 0.292 
B) -4.20 
C) 0.320 
D) -1.13 
E) More information is needed. 
A) 0.292 
B) -4.20 
C) 0.320 
D) -1.13 
E) More information is needed.

Question 12

Consider the reaction: Ag+ (aq)+ Cl- (aq)→ AgCl (s)
Given the following table of thermodynamic data,   determine the temperature (in °C)above which the reaction is nonspontaneous under standard conditions.

Accepted Answer

A) 1230 
B) 150 
C) 432 
D) 133 
E) 1640 
A) 1230 
B) 150 
C) 432 
D) 133 
E) 1640

Question 13

The equilibrium constant for the following reaction is 3.0 ×   at 25 °C.   (g)+ 3   (g)   2N   (g) The value of ΔG° for this reaction is ________ kJ/mol.

Accepted Answer

A) 22 
B) -4.1 
C) 4.1 
D) -48 
E) -22 
A) 22 
B) -4.1 
C) 4.1 
D) -48 
E) -22

Question 14

Which one of the following processes produces a decrease in the entropy of the system?

Accepted Answer

A) freezing of Fe(l)into Fe(s) 
B) evaporation of liquid ethanol into gaseous ethanol 
C) dissolution of LiOH(s)in water 
D) melting ice to form water 
E) mixing of two gases into one container 
A) freezing of Fe(l)into Fe(s) 
B) evaporation of liquid ethanol into gaseous ethanol 
C) dissolution of LiOH(s)in water 
D) melting ice to form water 
E) mixing of two gases into one container

Question 15

Consider the reaction: FeO (s)+ Fe (s)+ O2 (g)→ Fe2O3 (s)
Given the following table of thermodynamic data,   determine the temperature (in °C)at which the reaction is nonspontaneous.

Accepted Answer

A) below 618.1 
B) above 2438 
C) above 756.3 
D) below 2438 
E) This reaction is spontaneous at all temperatures. 
A) below 618.1 
B) above 2438 
C) above 756.3 
D) below 2438 
E) This reaction is spontaneous at all temperatures.

Question 16

The value of ΔH° for the decomposition of gaseous sulfur dioxide to solid elemental sulfur and gaseous oxygen, SO2 (g)→ S (s,rhombic)+ O2 (g)
Is ________ kJ/mol.

Accepted Answer

A) 0.0 
B) +135.0 
C) -135.90 
D) -269.9 
E) +269.9 
A) 0.0 
B) +135.0 
C) -135.90 
D) -269.9 
E) +269.9

Question 17

Which of the following statements is true?

Accepted Answer

A) Processes that are spontaneous in one direction are spontaneous in the opposite direction. 
B) Processes are spontaneous because they occur at an observable rate. 
C) Spontaneity can depend on the temperature. 
D) All of the statements are true. 
A) Processes that are spontaneous in one direction are spontaneous in the opposite direction. 
B) Processes are spontaneous because they occur at an observable rate. 
C) Spontaneity can depend on the temperature. 
D) All of the statements are true.

Question 18

Which of the following has the largest entropy?

Accepted Answer

A) B2F4 (g) 
B) BF3 (g) 
C) B2H6 (g) 
D) BCl3 (l) 
E) B2O3 (s) 
A) B2F4 (g) 
B) BF3 (g) 
C) B2H6 (g) 
D) BCl3 (l) 
E) B2O3 (s)

Question 19

With thermodynamics,one cannot determine ________.

Accepted Answer

A) the speed of a reaction 
B) the direction of a spontaneous reaction 
C) the extent of a reaction 
D) the value of the equilibrium constant 
E) the temperature at which a reaction will be spontaneous 
A) the speed of a reaction 
B) the direction of a spontaneous reaction 
C) the extent of a reaction 
D) the value of the equilibrium constant 
E) the temperature at which a reaction will be spontaneous

Question 20

The value of ΔG° at 261.0 °C for the formation of phosphorous trichloride from its constituent elements,   (g)+   (g)→   (g) is ________ kJ/mol.At 25.0 °C for this reaction,ΔH° is -720.5 kJ/mol,ΔG° is   and   is

Accepted Answer

A) -579.6 
B) 6.81 ×   
C) 1.40 × 105 
D) -651.7 
E) -861.4 
A) -579.6 
B) 6.81 ×   
C) 1.40 × 105 
D) -651.7 
E) -861.4

Exam 19: Chemical Thermodynamics

The value of ΔS° for the decomposition of calcium chloride into its constituent elements, CaCl2 (s)→ Ca (s)+ Cl2 (g) Is ________ J/K ∙ mol.

A reversible process is one that ________.

The normal boiling point of water is 100.0 °C and its molar enthalpy of vaporization is 40.67 kJ/mol.What is the change in entropy in the system in J/K when 24.7 grams of steam at 1 atm condenses to a liquid at the normal boiling point?

The value of ΔH° for the formation of POCl3 from its constituent elements, P2 (g)+ O2 (g)+ 3Cl2 (g)→ 2POCl3 (g) Is ________ kJ/mol.

ΔS is positive for the reaction ________.

What is the equilibrium constant for a reaction at 25 °C.The value of ΔG° is -57.5 kJ/mol.

The value of ΔH° for the decomposition of POCl3 into its constituent elements, 2POCl3 (g)→ P2 (g)+ O2 (g)+ 3Cl2 (g) Is ________ kJ/mol.

Which of the following has the largest entropy?

At what temperature (in K)will a reaction become spontaneous? ΔH is 115.0 kJ/mol and ΔS is 75.00 J/K ∙ mol.

The value of ΔG° at 25 °C for the decomposition of POCl3 into its constituent elements, 2POCl3 (g)→ P2 (g)+ O2 (g)+ 3Cl2 (g) Is ________ kJ/mol.

The value of ΔG° for a reaction conducted at 25 °C is 3.05 kJ/mol.The equilibrium constant for a reaction is ________ at this temperature.

Consider the reaction: Ag+ (aq)+ Cl- (aq)→ AgCl (s) Given the following table of thermodynamic data, determine the temperature (in °C)above which the reaction is nonspontaneous under standard conditions.

The equilibrium constant for the following reaction is 3.0 × at 25 °C. (g)+ 3 (g) 2N (g) The value of ΔG° for this reaction is ________ kJ/mol.

Which one of the following processes produces a decrease in the entropy of the system?

Consider the reaction: FeO (s)+ Fe (s)+ O2 (g)→ Fe2O3 (s) Given the following table of thermodynamic data, determine the temperature (in °C)at which the reaction is nonspontaneous.

The value of ΔH° for the decomposition of gaseous sulfur dioxide to solid elemental sulfur and gaseous oxygen, SO2 (g)→ S (s,rhombic)+ O2 (g) Is ________ kJ/mol.

Which of the following statements is true?

Which of the following has the largest entropy?

With thermodynamics,one cannot determine ________.

The value of ΔG° at 261.0 °C for the formation of phosphorous trichloride from its constituent elements, (g)+ (g)→ (g) is ________ kJ/mol.At 25.0 °C for this reaction,ΔH° is -720.5 kJ/mol,ΔG° is and is

Introduction: Matter, energy, and Measurement

Atoms, molecules, and Ions

Chemical Reactions and Reaction Stoichiometry

Reactions in Aqueous Solution

Thermochemistry

Electronic Structure of Atoms

Periodic Properties of the Elements

Basic Concepts of Chemical Bonding

Molecular Geometry and Bonding Theories

Gases

Liquids and Intermolecular Forces

Solids and Modern Materials

Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acid-Base Equilibria

Additional Aspects of Aqueous Equilibria

Chemistry of the Environment

Electrochemistry

Nuclear Chemistry

Chemistry of the Nonmetals

Transition Metals and Coordination Chemistry

The Chemistry of Life: Organic and Biological Chemistry

Filters

The value of ΔS° for the decomposition of calcium chloride into its constituent elements, CaCl₂(s)→ Ca (s)+ Cl₂ (g) Is ________ J/K ∙ mol.

The value of ΔH° for the formation of POCl₃ from its constituent elements, P₂ (g)+ O₂ (g)+ 3Cl₂ (g)→ 2POCl₃ (g) Is ________ kJ/mol.

The value of ΔH° for the decomposition of POCl₃ into its constituent elements, 2POCl₃ (g)→ P₂ (g)+ O₂ (g)+ 3Cl₂ (g) Is ________ kJ/mol.

The value of ΔG° at 25 °C for the decomposition of POCl₃ into its constituent elements, 2POCl₃ (g)→ P₂ (g)+ O₂ (g)+ 3Cl₂ (g) Is ________ kJ/mol.

Consider the reaction: Ag⁺ (aq)+ Cl^- (aq)→ AgCl (s) Given the following table of thermodynamic data, determine the temperature (in °C)above which the reaction is nonspontaneous under standard conditions.

Consider the reaction: FeO (s)+ Fe (s)+ O₂(g)→ Fe₂O₃ (s) Given the following table of thermodynamic data, determine the temperature (in °C)at which the reaction is nonspontaneous.

The value of ΔH° for the decomposition of gaseous sulfur dioxide to solid elemental sulfur and gaseous oxygen, SO₂ (g)→ S (s,rhombic)+ O₂ (g) Is ________ kJ/mol.