Question 1

Which one of the following changes of state increases the entropy of the system?

Accepted Answer

A)  Condensation
B)  Cooling a gas
C)  Freezing
D)  Crystallization
E)  SublimationF) C) and E)
G) A) and B)

Question 2

Which of the following is always true for an endothermic process?

Accepted Answer

A)  q sys > 0, Δ S surr 
B)  q sys surr > 0
C)  q sys surr 
D)  q sys > 0, Δ S surr > 0
E)  w < 0F) B) and D)
G) C) and D)

Question 3

You are given pure samples of pentane, CH3CH2CH2CH2CH3(l) , and 1,3-pentadiene, CH2=CHCH=CHCH3(l) . What prediction would you make concerning their standard molar entropies at 298 K?

Accepted Answer

A)  S° pentane > S° 1, 3-pentadiene
B)  S° pentane 1, 3-pentadiene
C)  S° pentane ≈ S° 1, 3-pentadiene
D)  S° pentane = S° 1, 3-pentadiene + 2 S°H 2
E)  More information is needed to make reasonable predictions.F) D) and E)
G) B) and E)

Question 4

Calculate ΔG° for the reaction SiCl4(g)  + 2Mg(s)  → 2MgCl2(s)  + Si(s) 
4(g)  + 2Mg(s)  → 2MgCl2(s)  + Si(s)    A) 566.60 kJ B) 50.38 kJ C) 25.19 kJ D) −25.19 kJ E) −566.60 kJ" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  566.60 kJ
B)  50.38 kJ
C)  25.19 kJ
D)  −25.19 kJ
E)  −566.60 kJF) B) and D)
G) B) and E)

Question 5

Iron(III)  oxide can be reduced by carbon monoxide. Fe2O3(s)  + 3CO(g)  ⇄ 2Fe(s)  + 3CO2(g) 
Use the following thermodynamic data at 298 K to determine the equilibrium constant at this temperature.
2O3(s)  + 3CO(g)  ⇄ 2Fe(s)  + 3CO2(g)  Use the following thermodynamic data at 298 K to determine the equilibrium constant at this temperature.   A) 7.0 × 10 −6 B) 1.3 × 10 −3 C) 2.2 × 10 4 D) 1.4 × 10 5 E) > 2.0 × 10 5" class="answers-bank-image d-inline" rel="preload" >

Accepted Answer

A)  7.0 × 10 −6
B)  1.3 × 10 −3
C)  2.2 × 10 4
D)  1.4 × 10 5
E)  > 2.0 × 10 5F) A) and E)
G) D) and E)

Exam 20: Thermodynamics: Entropy, Free Energy, and Reaction Direction

Iron(III) oxide can be reduced by carbon monoxide. Fe₂O₃(s) + 3CO(g) ⇄ 2Fe(s) + 3CO₂(g) Use the following thermodynamic data at 298 K to determine the equilibrium constant at this temperature.

Correct Answer
verified

Calculate ΔG° for the reaction SiCl₄(g) + 2Mg(s) → 2MgCl₂(s) + Si(s)

Correct Answer
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Which one of the following changes of state increases the entropy of the system?

Correct Answer
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You are given pure samples of pentane, CH₃CH₂CH₂CH₂CH₃(l) , and 1,3-pentadiene, CH₂=CHCH=CHCH₃(l) . What prediction would you make concerning their standard molar entropies at 298 K?

Correct Answer
verified

Which of the following is always true for an endothermic process?

Correct Answer
verified

Exam 20: Thermodynamics: Entropy, Free Energy, and Reaction Direction

Iron(III) oxide can be reduced by carbon monoxide. Fe2O3(s) + 3CO(g) ⇄ 2Fe(s) + 3CO2(g) Use the following thermodynamic data at 298 K to determine the equilibrium constant at this temperature.

Correct AnswerverifiedShow Answer

Calculate ΔG° for the reaction SiCl4(g) + 2Mg(s) → 2MgCl2(s) + Si(s)

Correct AnswerverifiedShow Answer

Which one of the following changes of state increases the entropy of the system?

Correct AnswerverifiedShow Answer

You are given pure samples of pentane, CH3CH2CH2CH2CH3(l) , and 1,3-pentadiene, CH2=CHCH=CHCH3(l) . What prediction would you make concerning their standard molar entropies at 298 K?

Correct AnswerverifiedShow Answer

Which of the following is always true for an endothermic process?

Correct AnswerverifiedShow Answer

Iron(III) oxide can be reduced by carbon monoxide. Fe₂O₃(s) + 3CO(g) ⇄ 2Fe(s) + 3CO₂(g) Use the following thermodynamic data at 298 K to determine the equilibrium constant at this temperature.

Correct Answer
verified

Calculate ΔG° for the reaction SiCl₄(g) + 2Mg(s) → 2MgCl₂(s) + Si(s)

Correct Answer
verified

Correct Answer
verified

You are given pure samples of pentane, CH₃CH₂CH₂CH₂CH₃(l) , and 1,3-pentadiene, CH₂=CHCH=CHCH₃(l) . What prediction would you make concerning their standard molar entropies at 298 K?

Correct Answer
verified

Correct Answer
verified