Question 1

The quantity of energy gained by a system equals the quantity of energy gained by its surroundings.

Accepted Answer

A) True 
 B)False  False

Question 2

When a system is at equilibrium,________.

Accepted Answer

A) the reverse process is spontaneous but the forward process is not 
B) the forward and the reverse processes are both spontaneous 
C) the forward process is spontaneous but the reverse process is not 
D) the process is not spontaneous in either direction 
E) both forward and reverse processes have stopped 
A) the reverse process is spontaneous but the forward process is not 
B) the forward and the reverse processes are both spontaneous 
C) the forward process is spontaneous but the reverse process is not 
D) the process is not spontaneous in either direction 
E) both forward and reverse processes have stopped D

Question 3

For an isothermal process,ΔS = ________.

Accepted Answer

A) q 
B)    /T 
C) qrev 
D) T   
E) q + w 
A) q 
B)    /T 
C) qrev 
D) T   
E) q + w B

Question 4

The standard Gibbs free energy of formation of ________ is zero. 
(a) H2O (l)
(b)O(g)
(c) CL2(g)

Accepted Answer

A) (a)only 
B) (b)only 
C) (c)only 
D) (b)and (c) 
E) (a), (b), and (c) 
A) (a)only 
B) (b)only 
C) (c)only 
D) (b)and (c) 
E) (a), (b), and (c)

Question 5

In the Haber process,ammonia gas is synthesized from nitrogen gas and hydrogen gas.ΔG° at 298 K for this reaction is -33.3 kJ/mol.The value of ΔG at 298 K for a reaction mixture that consists of 1.9 atm nitrogen gas,2.3 atm hydrogen gas,and 0.85 atm ammonia gas is ________.

Accepted Answer

A) -1.0 
B) -4.09 ×   
C) -8.62 × 103 
D) -118.0 
E) -41.9 
A) -1.0 
B) -4.09 ×   
C) -8.62 × 103 
D) -118.0 
E) -41.9

Question 6

ΔS is positive for the reaction ________.

Accepted Answer

A) CaO (s)+ CO2 (g)→ CaCO3 (s) 
B) N2 (g)+ 3H2 (g)→ 2NH3 (g) 
C) 2SO3 (g)→ 2SO2 (g)+ O2 (g) 
D) Ag+ (aq)+ Cl- (aq)→ AgCl (s) 
E) H2O (l)→ H2O (s) 
A) CaO (s)+ CO2 (g)→ CaCO3 (s) 
B) N2 (g)+ 3H2 (g)→ 2NH3 (g) 
C) 2SO3 (g)→ 2SO2 (g)+ O2 (g) 
D) Ag+ (aq)+ Cl- (aq)→ AgCl (s) 
E) H2O (l)→ H2O (s)

Question 7

For an isothermal process,the entropy change of the surroundings is given by the equation:

Accepted Answer

A) ΔS = qsys T 
B) ΔS = -qsys T 
C) ΔS = q lnT 
D) ΔS = -q lnT 
E) ΔS = -qsys / T 
A) ΔS = qsys T 
B) ΔS = -qsys T 
C) ΔS = q lnT 
D) ΔS = -q lnT 
E) ΔS = -qsys / T

Question 8

The value of ΔG° at 25 °C for the formation of POCl3 from its constituent elements, P2 (g)+ O2 (g)+ 3Cl2 (g)→ 2POCl3 (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 9

Calculate ΔG∘ (in kJ/mol)for the following reaction at 1 atm and 25 °C:
C2H6 (g)+ O2 (g)→ CO2 (g)+ H2O (l)(unbalanced)
ΔHf∘ C2H6 (g)= -84.7 kJ/mol; S∘ C2H6 (g)= 229.5 J/K ∙ mol;
ΔHf∘ CO2 (g)= -393.5 kJ/mol; S∘ CO2 (g)= 213.6 J/K ∙ mol;
ΔHf∘ H2O (l)= -285.8 kJ/mol; S∘H2O (l)= 69.9 J/K ∙ mol;
S∘O2 (g)= 205.0 J/K ∙ mol

Accepted Answer

Question 10

The value of ΔH° for the formation of calcium chloride from its constituent elements, Ca (s)+ Cl2 (g)→ CaCl2 (s)
Is ________ kJ/mol.

Accepted Answer

A) 0.00 
B) -397.9 
C) +397.9 
D) -795.8 
E) +795.8 
A) 0.00 
B) -397.9 
C) +397.9 
D) -795.8 
E) +795.8

Question 11

The normal boiling point of methanol is   and the molar enthalpy of vaporization if 71.8 kJ/mol.The value of ΔS when 1.75 mol of   vaporizes at 64.7 °C is

Accepted Answer

A) 0.372 
B) 372 
C) 1.94 ×   
D) 4.24 ×   
E) 1.94 
A) 0.372 
B) 372 
C) 1.94 ×   
D) 4.24 ×   
E) 1.94

Question 12

The value of ΔG° at 181.0 °C for the formation of calcium chloride from calcium metal and chlorine gas is ________ kJ/mol.At 25.0 °C for this reaction,ΔH° is -795.8 kJ/mol,ΔG° is -748.1 kJ/mol,and   is

Accepted Answer

A) 7.18 ×   
B) -868.4 
C) -766.9 
D) -723.2 
E) 2.81 ×   
A) 7.18 ×   
B) -868.4 
C) -766.9 
D) -723.2 
E) 2.81 ×

Question 13

The value of ΔS° for the decomposition of phosphorous trichloride into its constituent elements, 2PCl3 (g)→ P2 (g)+ 3Cl2( g)
Is ________ J/K ∙ mol.

Accepted Answer

A) -311.7 
B) +311.7 
C) +263.6 
D) +129.4 
E) -129.4 
A) -311.7 
B) +311.7 
C) +263.6 
D) +129.4 
E) -129.4

Question 14

The value of ΔH° for the decomposition of gaseous sulfur trioxide to its component elements, 
2SO3 (g)→ 2S (s,rhombic)+ 3O2 (g)
Is ________ kJ/mol.

Accepted Answer

A) +790.4 
B) -790.4 
C) +395.2 
D) -395.2 
E) +105.1 
A) +790.4 
B) -790.4 
C) +395.2 
D) -395.2 
E) +105.1

Question 15

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

Accepted Answer

A) +269.9 
B) -269.9 
C) +0.00 
D) -11.6 
E) +11.6 
A) +269.9 
B) -269.9 
C) +0.00 
D) -11.6 
E) +11.6

Question 16

For the reaction C(s)+   O(g)→ CO(g)+   (g)
ΔH° = 133.3 kJ/mol and ΔS° = 121.6 J/K ∙ mol at 298 K.At temperatures greater than ________ °C this reaction is spontaneous under standard conditions.

Accepted Answer

A) 273 
B) 325 
C) 552 
D) 823 
E) 1096 
A) 273 
B) 325 
C) 552 
D) 823 
E) 1096

Question 17

Phosphorous and chlorine gases combine to produce phosphorous trichloride.ΔG° at 298 K for this reaction is -642.9 kJ/mol.The value of ΔG at 298 K for a reaction mixture that consists of     and   is ________.

Accepted Answer

A) -650.1 
B) -34.9 
C) -714.1 
D) -4.46 ×   
E) -7.86 × 103 
A) -650.1 
B) -34.9 
C) -714.1 
D) -4.46 ×   
E) -7.86 × 103

Question 18

The value of ΔH° for the decomposition of phosphorous trichloride into its constituent elements, 2PCl3 (g)→ P2 (g)+ 3Cl2 (g)
Is ________ kJ/mol.

Accepted Answer

A) +576.2 
B) -288.1 
C) +720.5 
D) +288.1 
E) -720.5 
A) +576.2 
B) -288.1 
C) +720.5 
D) +288.1 
E) -720.5

Question 19

The value of ΔG° at 373 K for the oxidation of solid elemental sulfur to gaseous sulfur dioxide is ________ kJ/mol.At 298 K,ΔH° for this reaction is -269.9 kJ/mol,and ΔS° is +11.6 J/K.

Accepted Answer

A) -300.4 
B) -274.2 
C) -4,597 
D) +300.4 
E) +4,597 
A) -300.4 
B) -274.2 
C) -4,597 
D) +300.4 
E) +4,597

Question 20

Calculate ΔG° (in kJ/mol)for the following reaction at 1 atm and 25 °C:
C2H6 (g)+ O2 (g)→ CO2 (g)+ H2O (l)(unbalanced)
ΔGf° C2H6 (g)= -32.89 kJ/mol; ΔGf° CO2 (g)= -394.4 kJ/mol; ΔGf° H2O (l)= -237.13 kJ/mol

Accepted Answer

Exam 19: Chemical Thermodynamics

The quantity of energy gained by a system equals the quantity of energy gained by its surroundings.

When a system is at equilibrium,________.

For an isothermal process,ΔS = ________.

The standard Gibbs free energy of formation of ________ is zero. (a) H2O (l) (b)O(g) (c) CL2(g)

In the Haber process,ammonia gas is synthesized from nitrogen gas and hydrogen gas.ΔG° at 298 K for this reaction is -33.3 kJ/mol.The value of ΔG at 298 K for a reaction mixture that consists of 1.9 atm nitrogen gas,2.3 atm hydrogen gas,and 0.85 atm ammonia gas is ________.

ΔS is positive for the reaction ________.

For an isothermal process,the entropy change of the surroundings is given by the equation:

The value of ΔG° at 25 °C 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 formation of calcium chloride from its constituent elements, Ca (s)+ Cl2 (g)→ CaCl2 (s) Is ________ kJ/mol.

The normal boiling point of methanol is and the molar enthalpy of vaporization if 71.8 kJ/mol.The value of ΔS when 1.75 mol of vaporizes at 64.7 °C is

The value of ΔG° at 181.0 °C for the formation of calcium chloride from calcium metal and chlorine gas is ________ kJ/mol.At 25.0 °C for this reaction,ΔH° is -795.8 kJ/mol,ΔG° is -748.1 kJ/mol,and is

The value of ΔS° for the decomposition of phosphorous trichloride into its constituent elements, 2PCl3 (g)→ P2 (g)+ 3Cl2( g) Is ________ J/K ∙ mol.

The value of ΔH° for the decomposition of gaseous sulfur trioxide to its component elements, 2SO3 (g)→ 2S (s,rhombic)+ 3O2 (g) Is ________ kJ/mol.

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

For the reaction C(s)+ O(g)→ CO(g)+ (g) ΔH° = 133.3 kJ/mol and ΔS° = 121.6 J/K ∙ mol at 298 K.At temperatures greater than ________ °C this reaction is spontaneous under standard conditions.

Phosphorous and chlorine gases combine to produce phosphorous trichloride.ΔG° at 298 K for this reaction is -642.9 kJ/mol.The value of ΔG at 298 K for a reaction mixture that consists of and is ________.

The value of ΔH° for the decomposition of phosphorous trichloride into its constituent elements, 2PCl3 (g)→ P2 (g)+ 3Cl2 (g) Is ________ kJ/mol.

The value of ΔG° at 373 K for the oxidation of solid elemental sulfur to gaseous sulfur dioxide is ________ kJ/mol.At 298 K,ΔH° for this reaction is -269.9 kJ/mol,and ΔS° is +11.6 J/K.

Calculate ΔG° (in kJ/mol)for the following reaction at 1 atm and 25 °C: C2H6 (g)+ O2 (g)→ CO2 (g)+ H2O (l)(unbalanced) ΔGf° C2H6 (g)= -32.89 kJ/mol; ΔGf° CO2 (g)= -394.4 kJ/mol; ΔGf° H2O (l)= -237.13 kJ/mol

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 standard Gibbs free energy of formation of ________ is zero. (a) H₂O (l) (b)O(g) (c) CL₂(g)

The value of ΔG° at 25 °C 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 formation of calcium chloride from its constituent elements, Ca (s)+ Cl₂ (g)→ CaCl₂ (s) Is ________ kJ/mol.

The value of ΔS° for the decomposition of phosphorous trichloride into its constituent elements, 2PCl₃(g)→ P₂(g)+ 3Cl₂( g) Is ________ J/K ∙ mol.

The value of ΔH° for the decomposition of gaseous sulfur trioxide to its component elements, 2SO₃ (g)→ 2S (s,rhombic)+ 3O₂ (g) Is ________ kJ/mol.

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

The value of ΔH° for the decomposition of phosphorous trichloride into its constituent elements, 2PCl₃ (g)→ P₂ (g)+ 3Cl₂ (g) Is ________ kJ/mol.

Calculate ΔG°(in kJ/mol)for the following reaction at 1 atm and 25 °C: C₂H₆ (g)+ O₂ (g)→ CO₂ (g)+ H₂O (l)(unbalanced) ΔG_f° C₂H₆ (g)= -32.89 kJ/mol; ΔG_f°CO₂ (g)= -394.4 kJ/mol; ΔG_f° H₂O (l)= -237.13 kJ/mol