Question 1

The entropy of a NaCl crystal is __________

Accepted Answer

A)  an intensive property and a state function. 
B)  an intensive property and a path function. 
C)  an extensive property and a state function. 
D)  an extensive property and a path function. 
E)  not appropriately described in terms of an intensive property, an extensive property, a state function, or a path function. 
A)  an intensive property and a state function. 
B)  an intensive property and a path function. 
C)  an extensive property and a state function. 
D)  an extensive property and a path function. 
E)  not appropriately described in terms of an intensive property, an extensive property, a state function, or a path function.

Question 2

At what temperature does the Fe(s) F3S3S3W1F1F1F10 Fe(g) phase transition occur? F1F1F1S1F1F1F10H = 415.5 kJ/mol; F1F1F1S1F1F1F10S = 153.4 J/mol · K.

Accepted Answer

A)  2162°F 
B)  2435°F 
C)  4352°F 
D)  4416°F 
E)  2709°F 
A)  2162°F 
B)  2435°F 
C)  4352°F 
D)  4416°F 
E)  2709°F

Question 3

Name and state the first three laws of thermodynamics.

Accepted Answer

First law: the energy of the u

Question 4

Heat transfer from the system to the surroundings has a large effect on F1F1F1S1F1F1F10Ssurr ___________

Accepted Answer

A)  when the temperature of the surroundings is low. 
B)  when the temperature of the surroundings is high. 
C)  when the temperature of the system is low. 
D)  when the temperature of the system is high. 
E)  at any temperature as the amount of heat transferred is independent of temperature. 
A)  when the temperature of the surroundings is low. 
B)  when the temperature of the surroundings is high. 
C)  when the temperature of the system is low. 
D)  when the temperature of the system is high. 
E)  at any temperature as the amount of heat transferred is independent of temperature.

Question 5

According to the second law of thermodynamics, the change in the entropy of the universe (F1F1F1S1F1F1F10Suniv) during a spontaneous reaction is __________

Accepted Answer

A)  zero. 
B)  negative. 
C)  positive. 
D)  less than the change in entropy of the system (F1F1F1S1F1F1F10Ssys). 
E)  greater than the change in entropy of the system (F1F1F1S1F1F1F10Ssys). 
A)  zero. 
B)  negative. 
C)  positive. 
D)  less than the change in entropy of the system (F1F1F1S1F1F1F10Ssys). 
E)  greater than the change in entropy of the system (F1F1F1S1F1F1F10Ssys).

Question 6

If 1 mol of ice melts at its melting point of 273 K, the entropy change for the ice is 22.0 J/K. If the ice melts in someone's hand at 34°C, what is the change in the entropy of the universe? Assume a final temperature for the water of 0°C. The enthalpy of fusion for ice is 6.01 kJ/mol.

Accepted Answer

A)  +19.6 J/K 
B)  -19.6 J/K 
C)  +2.4 J/K 
D)  -2.4 J/K 
E)  +41.5 J/K 
A)  +19.6 J/K 
B)  -19.6 J/K 
C)  +2.4 J/K 
D)  -2.4 J/K 
E)  +41.5 J/K

Question 7

The standard entropy of diamond is 2.4 J/mol · K. Calculate the entropy per carbon atom in diamond and the number of microstates for each atom. Discuss the number of microstates in terms of the molecular motions accessible to each carbon atom.

Accepted Answer

S_atom = 2.4 J/mol · K/6.022 F1F1F1S1F1F1F10

Question 8

Give an example of a spontaneous and a nonspontaneous chemical process and the sign of the entropy change for the universe for each.

Accepted Answer

The burning of alkane gases and the free

Question 9

The equilibrium vapor pressure for benzene is 94.4 mm Hg. When liquid benzene is in equilibrium with its vapor, we must have __________

Accepted Answer

A) "F1F1F1S1F1F1F10G" = 0 and "F1F1F1S1F1F1F10G°" = 0 B) "F1F1F1S1F1F1F10G" = 0 and "F1F1F1S1F1F1F10G°" > 0 C) "F1F1F1S1F1F1F10G" = 0 and "F1F1F1S1F1F1F10G°" 0 and "F1F1F1S1F1F1F10G°" = 0 E) "F1F1F1S1F1F1F10G" < 0 and "F1F1F1S1F1F1F10G°" = 0 A) "F1F1F1S1F1F1F10G" = 0 and "F1F1F1S1F1F1F10G°" = 0 B) "F1F1F1S1F1F1F10G" = 0 and "F1F1F1S1F1F1F10G°" > 0 C) "F1F1F1S1F1F1F10G" = 0 and "F1F1F1S1F1F1F10G°" 0 and "F1F1F1S1F1F1F10G°" = 0 E) "F1F1F1S1F1F1F10G" < 0 and "F1F1F1S1F1F1F10G°" = 0

Question 10

Which of the following must be true for a spontaneous exothermic process?

Accepted Answer

A)  only that F1F1F1S1F1F1F10Ssys sys > 0 
C)  both F1F1F1S1F1F1F10Ssys sys surr 
D)  both F1F1F1S1F1F1F10Ssys sys > the magnitude of F1F1F1S1F1F1F10Ssurr 
E)  either F1F1F1S1F1F1F10Ssys > 0 or F1F1F1S1F1F1F10Ssys sys surr 
A)  only that F1F1F1S1F1F1F10Ssys sys > 0 
C)  both F1F1F1S1F1F1F10Ssys sys surr 
D)  both F1F1F1S1F1F1F10Ssys sys > the magnitude of F1F1F1S1F1F1F10Ssurr 
E)  either F1F1F1S1F1F1F10Ssys > 0 or F1F1F1S1F1F1F10Ssys sys surr

Question 11

Indicate which of the following has the lowest standard molar entropy (S°).

Accepted Answer

A)  CH4(g) 
B)  CH3CH2OH(   ) 
C)  H2O(s) 
D)  Na(s) 
E)  He(g) 
A)  CH4(g) 
B)  CH3CH2OH(   ) 
C)  H2O(s) 
D)  Na(s) 
E)  He(g)

Question 12

The entropy change in a system (F1F1F1S1F1F1F10Ssys) during a spontaneous process must be __________

Accepted Answer

A)  greater than zero. 
B)  less than zero. 
C)  equal to zero. 
D)  greater than or equal to zero. 
E)  greater than, less than, or equal to zero. 
A)  greater than zero. 
B)  less than zero. 
C)  equal to zero. 
D)  greater than or equal to zero. 
E)  greater than, less than, or equal to zero.

Question 13

Indicate which of the following has the highest entropy at 298 K.

Accepted Answer

A)  0.5 g of HCN 
B)  1 mol of HCN 
C)  2 kg of HCN 
D)  2 mol of HCN 
E)  All of the above have the same entropy at 298 K. 
A)  0.5 g of HCN 
B)  1 mol of HCN 
C)  2 kg of HCN 
D)  2 mol of HCN 
E)  All of the above have the same entropy at 298 K.

Question 14

What is the entropy change to the surroundings when 1 mol of ice melts in someone's hand if the hand temperature is 32°C? Assume a final temperature for the water of 0°C. The heat of fusion of ice is 6.01 kJ/mol.

Accepted Answer

A)  -188 J/K 
B)  -22.0 J/K 
C)  -19.7 J/K 
D)  +19.7 J/K 
E)  +188 J/K 
A)  -188 J/K 
B)  -22.0 J/K 
C)  -19.7 J/K 
D)  +19.7 J/K 
E)  +188 J/K

Question 15

Considering the tabulated values for the thermodynamic properties of oxygen gas, why is the standard entropy nonzero but the standard enthalpy and free energy of formation are zero?

Accepted Answer

The standard entropy is the entropy of O

Question 16

The standard molar entropy of lead(II) bromide (PbBr2) is 161 J/mol · K. What is the entropy of 2.45 g of PbBr2?

Accepted Answer

A)  +1.07 J/K 
B)  -1.07 J/K 
C)  +161 J/K 
D)  -161 J/K 
E)  0 J/K 
A)  +1.07 J/K 
B)  -1.07 J/K 
C)  +161 J/K 
D)  -161 J/K 
E)  0 J/K

Question 17

Determine F1F1F1S1F1F1F10Grxn for C4H10(   ) +   O2(g) F3S3S3W1F1F1F10 4CO2(g) + 5H2O(g) given the following. Substance
F1F1F1S1F1F1F10G    (J/mol · K)
C4H10(   )
-15)0
CO2(g)
-394.4
H2O(g)
-228.57

Accepted Answer

A)  -2705 kJ/mol 
B)  -608.0 kJ/mol 
C)  -1791 kJ/mol 
D)  -3457 kJ/mol 
E)  +608.0 kJ/mol 
A)  -2705 kJ/mol 
B)  -608.0 kJ/mol 
C)  -1791 kJ/mol 
D)  -3457 kJ/mol 
E)  +608.0 kJ/mol

Question 18

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 19

Benzene is a liquid under standard conditions. The standard free-energy change for the evaporation of liquid benzene to form benzene vapor is +5.2 kJ/mol. If liquid benzene is placed in an open container under standard conditions, __________

Accepted Answer

A)  it will not evaporate. 
B)  it will partially evaporate with the equilibrium vapor pressure being less than 1 bar. 
C)  it will partially evaporate with the equilibrium vapor pressure being equal to 1 bar. 
D)  it will partially evaporate with the equilibrium vapor pressure being greater than 1 bar. 
E)  it will completely evaporate. 
A)  it will not evaporate. 
B)  it will partially evaporate with the equilibrium vapor pressure being less than 1 bar. 
C)  it will partially evaporate with the equilibrium vapor pressure being equal to 1 bar. 
D)  it will partially evaporate with the equilibrium vapor pressure being greater than 1 bar. 
E)  it will completely evaporate.

Question 20

Which of the following is in the correct order of standard state entropy?
(I)Diamond 3 2

Accepted Answer

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

Exam 14: Thermodynamics: Spontaneous Processes, Entropy, and Free Energy

The entropy of a NaCl crystal is __________

At what temperature does the Fe(s)  Fe(g) phase transition occur? H = 415.5 kJ/mol; S = 153.4 J/mol · K.

Name and state the first three laws of thermodynamics.

Heat transfer from the system to the surroundings has a large effect on Ssurr ___________

According to the second law of thermodynamics, the change in the entropy of the universe (Suniv) during a spontaneous reaction is __________

If 1 mol of ice melts at its melting point of 273 K, the entropy change for the ice is 22.0 J/K. If the ice melts in someone's hand at 34°C, what is the change in the entropy of the universe? Assume a final temperature for the water of 0°C. The enthalpy of fusion for ice is 6.01 kJ/mol.

The standard entropy of diamond is 2.4 J/mol · K. Calculate the entropy per carbon atom in diamond and the number of microstates for each atom. Discuss the number of microstates in terms of the molecular motions accessible to each carbon atom.

Give an example of a spontaneous and a nonspontaneous chemical process and the sign of the entropy change for the universe for each.

The equilibrium vapor pressure for benzene is 94.4 mm Hg. When liquid benzene is in equilibrium with its vapor, we must have __________

Which of the following must be true for a spontaneous exothermic process?

Indicate which of the following has the lowest standard molar entropy (S°).

The entropy change in a system (Ssys) during a spontaneous process must be __________

Indicate which of the following has the highest entropy at 298 K.

What is the entropy change to the surroundings when 1 mol of ice melts in someone's hand if the hand temperature is 32°C? Assume a final temperature for the water of 0°C. The heat of fusion of ice is 6.01 kJ/mol.

Considering the tabulated values for the thermodynamic properties of oxygen gas, why is the standard entropy nonzero but the standard enthalpy and free energy of formation are zero?

The standard molar entropy of lead(II) bromide (PbBr2) is 161 J/mol · K. What is the entropy of 2.45 g of PbBr2?

Determine Grxn for C4H10( ) + O2(g)  4CO2(g) + 5H2O(g) given the following. Substance G (J/mol · K) C4H10( ) -15)0 CO2(g) -394.4 H2O(g) -228.57

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.

Benzene is a liquid under standard conditions. The standard free-energy change for the evaporation of liquid benzene to form benzene vapor is +5.2 kJ/mol. If liquid benzene is placed in an open container under standard conditions, __________

Which of the following is in the correct order of standard state entropy? (I)Diamond < graphite (II)Liquid water < solid water (III)NH3 < H2

Matter, Energy, and the Origins of the Universe

Atoms, Ions, and Compounds

Chemical Reactions and Earths Composition

Solution Chemistry and the Hydrosphere

Thermochemistry

Properties of Gases: the Air We Breathe

Electrons in Atoms and Periodic Properties

Chemical Bonding and Climate Change

Molecular Geometry and Bonding Theories

Forces Between Ions and Molecules

Solutions and Their Colligative Properties

The Chemistry of Solids

Organic Chemistry: Fuels, Pharmaceuticals, and Materials

Chemical Kinetics

Chemical Equilibrium

Equilibrium in the Aqueous Phase

The Colorful Chemistry of Metals

Electrochemistry and the Quest for Clean Energy

Biochemistry: the Compounds of Life

Nuclear Chemistry

Life and the Periodic Table

Filters

At what temperature does the Fe(s)  Fe(g) phase transition occur? H= 415.5 kJ/mol; S = 153.4 J/mol · K.

Heat transfer from the system to the surroundings has a large effect on S_surr ___________

According to the second law of thermodynamics, the change in the entropy of the universe (S_univ) during a spontaneous reaction is __________

The entropy change in a system (S_sys) during a spontaneous process must be __________

The standard molar entropy of lead(II) bromide (PbBr₂) is 161 J/mol · K. What is the entropy of 2.45 g of PbBr₂?

Determine G_rxn for C₄H₁₀( ) + O₂(g)  4CO₂(g) + 5H₂O(g) given the following. Substance G (J/mol · K) C₄H₁₀( ) -15)0 CO₂(g) -394.4 H₂O(g) -228.57

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.

Which of the following is in the correct order of standard state entropy? (I)Diamond < graphite (II)Liquid water < solid water (III)NH₃ < H₂