Question 1

Place the following in order of decreasing standard molar entropy. NaCl(s)Na3PO4(aq)NaCl(aq)

Accepted Answer

A)  NaCl(s) > NaCl(aq) > Na3PO4(aq) 
B)  NaCl(aq) > NaCl(s) > Na3PO4(aq) 
C)  Na3PO4(aq) > NaCl(aq) > NaCl(s) 
D)  NaCl(s) > Na3PO4(aq) > NaCl(aq) 
E)  NaCl(aq) > Na3PO4(aq) > NaCl(s)  C

Question 2

Match the following.

-Q = K

Accepted Answer

A)  K = 0
B)  ?rG > 0
C)  ( Δ\DeltaΔ rG 
D)  ?rG rG°
E)  equilibriumF) ?rG > ?rG°G) standard state  E

Question 3

Which of the following is TRUE if ln K is positive?

Accepted Answer

A)  ΔrG° is positive and the reaction is spontaneous in the forward direction.
B)  ΔrG° is negative and the reaction is spontaneous in the forward direction.
C)  ΔrG° is negative and the reaction is spontaneous in the reverse direction.
D)  ΔrG° is positive and the reaction is spontaneous in the reverse direction.
E)  ΔrG° is zero and the reaction is at equilibrium. B

Question 4

What is the sign of ΔSuniv for a biological system?

Accepted Answer

A)  positive
B)  negative
C)  zero
D)  It depends on the biological system.

Question 5

Match the following.

-Q > K

Accepted Answer

A)  K = 0
B)  ?rG > 0
C)  ( Δ\DeltaΔ rG 
D)  ?rG rG°
E)  equilibriumF) ?rG > ?rG°G) standard state

Question 6

Place the following in order of increasing molar entropy at 298 K. Ne Xe He Ar Kr

Accepted Answer

A)  He 
B)  Xe 
C)  Ar 
D)  Ar 
E)  He < Ne < Ar < Kr < Xe

Question 7

Determine the equilibrium constant for the following reaction at 498 K: 2 Hg(g)+ O2(g)→ 2HgO(s)ΔrH° = -304.2 kJ mol-1; ΔrS° = -414.2 J K-1 mol-1

Accepted Answer

A)  1.87 × 1010
B)  8.10 × 1031
C)  2.31 × 10-22
D)  5.34 × 10-11
E)  4.33 × 1021

Question 8

Determine ΔrG° at 298 K using the following information: H2(g)+ CO(g)→ CH2O(g) ΔrH°= +1.9 kJ mol-1; ΔrS°= -109.6 J K-1 mol-1

Accepted Answer

A)  +57.7 kJ mol-1
B)  -30.8 kJ mol-1
C)  +34.6 kJ mol-1
D)  -41.5 kJ mol-1
E)  +17.3 kJ mol-1

Question 9

Estimate ΔrG° for the following reaction at 387 K. HCN(g)+ 2H2(g)→ CH3NH2(g)ΔrH°= -158.0 kJ mol-1; ΔrS°= -219.9 J K-1 mol-1

Accepted Answer

A)  +243 kJ mol-1
B)  -72.9 kJ mol-1
C)  +84.9 kJ mol-1
D)  -92.5 kJ mol-1
E)  -188 kJ mol-1

Question 10

In the Haber process, ammonia is synthesized from nitrogen and hydrogen: N2(g)+ 3H2(g)→ 2NH3(g)
ΔrG° at 298 K for this reaction is -33.3 kJ mol-1. The value of ΔrG at 298 K for a reaction mixture that consists of 1.9 atm N2, 1.6 atm H2, and 0.65 atm NH3 is ________ kJ mol-1.

Accepted Answer

A)  -1.8
B)  -3.86 × 103
C)  -7.25 × 103
D)  -104.5
E)  -40.5

Question 11

Calculate ΔrG° at 298 K using the following information: 2H2S(g)+ 3O2(g)→ 2SO2(g)+ 2H2O(g)ΔrG° = ?
ΔfG°(kJ mol-1)-33.4 -300.1 -228.6

Accepted Answer

A)  +112.4 kJ mol-1
B)  -495.3 kJ mol-1
C)  -528.7 kJ mol-1
D)  +66.8 kJ mol-1
E)  -990.6 kJ mol-1

Question 12

Above what temperature does the following reaction become nonspontaneous? 2H2S(g)+ 3O2(g)→ 2SO2(g)+ 2H2O(g)ΔrH = -1036 kJ; ΔrS = -153.2 J K-1 mol-1

Accepted Answer

A)  6.762 × 103 K
B)  158.7 K
C)  298 K
D)  67.62 K
E)  1.587 × 103 K

Question 13

Calculate ΔrG° at 298 K using the following information: 2H2S(g)+ 3O2(g)→ 2SO2(g)+ 2H2O(g)ΔrG° = ?
ΔfH° (kJ mol-1)-20.6 -296.8 -241.8
S°(J K-1 mol-1)205.8 205.2 248.2 188.8

Accepted Answer

A)  -990.3 kJ mol-1
B)  +108.2 kJ mol-1
C)  -466.1 kJ mol-1
D)  +676.2 kJ mol-1
E)  -147.1 kJ mol-1

Question 14

Why is the quantity of energy required to recharge a battery greater than the quantity of work done?

Accepted Answer

The answer of Why is the quantity of energy required...

Question 15

Calculate ΔρS° for the following reaction. The S° for each species is shown below the reaction. P4(g)+ 10Cl2(g)→ 4PCl5(g)
S°(J K-1 mol-1)280.0 223.1 364.6

Accepted Answer

A)  -138.5 J K-1 mol-1
B)  -1052.6 J K-1 mol-1
C)  +171.3 J K-1 mol-1
D)  -583.6 J K-1 mol-1
E)  +2334.6 J K-1 mol-1

Question 16

Place the following in order of increasing molar entropy at 298 K. CO2 C3H8 SO

Accepted Answer

A)  CO2 3H8 
B)  C3H8 2 
C)  SO 2 3H8
D)  C3H8 2
E)  CO2 3H8

Question 17

Given the following equation, N2O(g)+ NO2(g)→ 3 NO(g)ΔrG° = -23.0 kJ mol-1
Calculate ΔrG° for the following reaction:
9NO(g)→ 3N2O(g)+ 3NO2(g)

Accepted Answer

A)  -23.0 kJ mol-1
B)  69.0 kJ mol-1
C)  -69.0 kJ mol-1
D)  -7.67 kJ mol-1
E)  23.0 kJ mol-1

Question 18

Consider a reaction that has a negative ΔrH and a negative ΔrS. Which of the following statements is TRUE?

Accepted Answer

A)  This reaction will be spontaneous only at low temperatures.
B)  This reaction will be spontaneous at all temperatures.
C)  This reaction will be nonspontaneous at all temperatures.
D)  This reaction will be nonspontaneous only at low temperatures.
E)  This reaction will be spontaneous only at absolute zero (0 Kelvin) .

Question 19

Calculate ΔrG° at 298 K using the following information: 4HNO3(g)+ 5N2H4(l)→ 7N2(g)+ 12H2O(l)ΔrG° = ?
ΔfH° (kJ mol-1)-133.9 50.6 -285.8
S°(J K-1 mol-1)266.9 121.2 191.6 70.0

Accepted Answer

A)  +4.90 × 103 kJ mol-1
B)  +3.90 × 103 kJ mol-1
C)  -2.04 × 103 kJ mol-1
D)  -3.15 × 103 kJ mol-1
E)  -3.30 × 103 kJ mol-1

Question 20

Calculate ΔrS° for the following reaction. The S° for each species is shown below the reaction. 4NH3(g)+ 5O2(g)→ 4NO(g)+ 6H2O(g)
S°(J K-1 mol-1)192.8 205.2 210.8 188.8

Accepted Answer

A)  +287.4 J K-1 mol-1
B)  -401.2 J K-1 mol-1
C)  +160.0 J K-1 mol-1
D)  -336.6 J K-1 mol-1
E)  +178.8 J K-1 mol-1

Exam 17: Gibbs Energy and Thermodynamics

Place the following in order of decreasing standard molar entropy. NaCl(s) Na₃PO₄(aq) NaCl(aq)

Match the following. -Q = K

Which of the following is TRUE if ln K is positive?

What is the sign of ΔS_univ for a biological system?

Match the following. -Q > K

Place the following in order of increasing molar entropy at 298 K. Ne Xe He Ar Kr

Determine the equilibrium constant for the following reaction at 498 K: 2 Hg(g) + O₂(g) → 2HgO(s) Δ_rH° = -304.2 kJ mol^-1; Δ_rS° = -414.2 J K^-1 mol^-1

Determine Δ_rG° at 298 K using the following information: H₂(g) + CO(g) → CH₂O(g) Δ_rH°= +1.9 kJ mol^-1; Δ_rS°= -109.6 J K^-1mol^-1

Estimate Δ_rG° for the following reaction at 387 K. HCN(g) + 2H₂(g) → CH₃NH₂(g) Δ_rH°= -158.0 kJ mol^-1; Δ_rS°= -219.9 J K^-1 mol^-1

In the Haber process, ammonia is synthesized from nitrogen and hydrogen: N₂(g) + 3H₂(g) → 2NH₃(g) Δ_rG° at 298 K for this reaction is -33.3 kJ mol^-1. The value of Δ_rG at 298 K for a reaction mixture that consists of 1.9 atm N₂, 1.6 atm H₂, and 0.65 atm NH₃ is ________ kJ mol^-1.

Calculate Δ_rG° at 298 K using the following information: 2H₂S(g) + 3O₂(g) → 2SO₂(g) + 2H₂O(g) Δ_rG°= ? Δ_fG°(kJ mol^-1) -33.4 -300.1 -228.6

Above what temperature does the following reaction become nonspontaneous? 2H₂S(g) + 3O₂(g) → 2SO₂(g) + 2H₂O(g) Δ_rH = -1036 kJ; Δ_rS = -153.2 J K^-1 mol^-1

Calculate Δ_rG° at 298 K using the following information: 2H₂S(g) + 3O₂(g) → 2SO₂(g) + 2H₂O(g) Δ_rG°= ? Δ_fH° (kJ mol^-1) -20.6 -296.8 -241.8 S°(J K^-1 mol^-1) 205.8 205.2 248.2 188.8

Why is the quantity of energy required to recharge a battery greater than the quantity of work done?

Calculate ΔρS° for the following reaction. The S° for each species is shown below the reaction. P₄(g) + 10Cl₂(g) → 4PCl₅(g) S°(J K^-1 mol^-1) 280.0 223.1 364.6

Place the following in order of increasing molar entropy at 298 K. CO₂ C₃H₈ SO

Given the following equation, N₂O(g) + NO₂(g) → 3 NO(g) Δ_rG° = -23.0 kJ mol^-1 Calculate Δ_rG° for the following reaction: 9NO(g) → 3N₂O(g) + 3NO₂(g)

Consider a reaction that has a negative Δ_rH and a negative Δ_rS. Which of the following statements is TRUE?

Calculate Δ_rG° at 298 K using the following information: 4HNO₃(g) + 5N₂H₄(l) → 7N₂(g) + 12H₂O(l) Δ_rG°= ? Δ_fH° (kJ mol^-1) -133.9 50.6 -285.8 S°(J K^-1 mol^-1) 266.9 121.2 191.6 70.0

Calculate Δ_rS° for the following reaction. The S° for each species is shown below the reaction. 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g) S°(J K^-1 mol^-1) 192.8 205.2 210.8 188.8

Exam 17: Gibbs Energy and Thermodynamics

Place the following in order of decreasing standard molar entropy. NaCl(s) Na3PO4(aq) NaCl(aq)

Match the following. -Q = K

Which of the following is TRUE if ln K is positive?

What is the sign of ΔSuniv for a biological system?

Match the following. -Q > K

Place the following in order of increasing molar entropy at 298 K. Ne Xe He Ar Kr

Determine the equilibrium constant for the following reaction at 498 K: 2 Hg(g) + O2(g) → 2HgO(s) ΔrH° = -304.2 kJ mol-1; ΔrS° = -414.2 J K-1 mol-1

Determine ΔrG° at 298 K using the following information: H2(g) + CO(g) → CH2O(g) ΔrH°= +1.9 kJ mol-1; ΔrS°= -109.6 J K-1 mol-1

Estimate ΔrG° for the following reaction at 387 K. HCN(g) + 2H2(g) → CH3NH2(g) ΔrH°= -158.0 kJ mol-1; ΔrS°= -219.9 J K-1 mol-1

In the Haber process, ammonia is synthesized from nitrogen and hydrogen: N2(g) + 3H2(g) → 2NH3(g) ΔrG° at 298 K for this reaction is -33.3 kJ mol-1. The value of ΔrG at 298 K for a reaction mixture that consists of 1.9 atm N2, 1.6 atm H2, and 0.65 atm NH3 is ________ kJ mol-1.

Calculate ΔrG° at 298 K using the following information: 2H2S(g) + 3O2(g) → 2SO2(g) + 2H2O(g) ΔrG° = ? ΔfG°(kJ mol-1) -33.4 -300.1 -228.6

Above what temperature does the following reaction become nonspontaneous? 2H2S(g) + 3O2(g) → 2SO2(g) + 2H2O(g) ΔrH = -1036 kJ; ΔrS = -153.2 J K-1 mol-1

Calculate ΔrG° at 298 K using the following information: 2H2S(g) + 3O2(g) → 2SO2(g) + 2H2O(g) ΔrG° = ? ΔfH° (kJ mol-1) -20.6 -296.8 -241.8 S°(J K-1 mol-1) 205.8 205.2 248.2 188.8

Why is the quantity of energy required to recharge a battery greater than the quantity of work done?

Calculate ΔρS° for the following reaction. The S° for each species is shown below the reaction. P4(g) + 10Cl2(g) → 4PCl5(g) S°(J K-1 mol-1) 280.0 223.1 364.6

Place the following in order of increasing molar entropy at 298 K. CO2 C3H8 SO

Given the following equation, N2O(g) + NO2(g) → 3 NO(g) ΔrG° = -23.0 kJ mol-1 Calculate ΔrG° for the following reaction: 9NO(g) → 3N2O(g) + 3NO2(g)

Consider a reaction that has a negative ΔrH and a negative ΔrS. Which of the following statements is TRUE?

Calculate ΔrG° at 298 K using the following information: 4HNO3(g) + 5N2H4(l) → 7N2(g) + 12H2O(l) ΔrG° = ? ΔfH° (kJ mol-1) -133.9 50.6 -285.8 S°(J K-1 mol-1) 266.9 121.2 191.6 70.0

Calculate ΔrS° for the following reaction. The S° for each species is shown below the reaction. 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(g) S°(J K-1 mol-1) 192.8 205.2 210.8 188.8

Place the following in order of decreasing standard molar entropy. NaCl(s) Na₃PO₄(aq) NaCl(aq)

What is the sign of ΔS_univ for a biological system?

Determine the equilibrium constant for the following reaction at 498 K: 2 Hg(g) + O₂(g) → 2HgO(s) Δ_rH° = -304.2 kJ mol^-1; Δ_rS° = -414.2 J K^-1 mol^-1

Determine Δ_rG° at 298 K using the following information: H₂(g) + CO(g) → CH₂O(g) Δ_rH°= +1.9 kJ mol^-1; Δ_rS°= -109.6 J K^-1mol^-1

Estimate Δ_rG° for the following reaction at 387 K. HCN(g) + 2H₂(g) → CH₃NH₂(g) Δ_rH°= -158.0 kJ mol^-1; Δ_rS°= -219.9 J K^-1 mol^-1

In the Haber process, ammonia is synthesized from nitrogen and hydrogen: N₂(g) + 3H₂(g) → 2NH₃(g) Δ_rG° at 298 K for this reaction is -33.3 kJ mol^-1. The value of Δ_rG at 298 K for a reaction mixture that consists of 1.9 atm N₂, 1.6 atm H₂, and 0.65 atm NH₃ is ________ kJ mol^-1.

Calculate Δ_rG° at 298 K using the following information: 2H₂S(g) + 3O₂(g) → 2SO₂(g) + 2H₂O(g) Δ_rG°= ? Δ_fG°(kJ mol^-1) -33.4 -300.1 -228.6

Above what temperature does the following reaction become nonspontaneous? 2H₂S(g) + 3O₂(g) → 2SO₂(g) + 2H₂O(g) Δ_rH = -1036 kJ; Δ_rS = -153.2 J K^-1 mol^-1

Calculate Δ_rG° at 298 K using the following information: 2H₂S(g) + 3O₂(g) → 2SO₂(g) + 2H₂O(g) Δ_rG°= ? Δ_fH° (kJ mol^-1) -20.6 -296.8 -241.8 S°(J K^-1 mol^-1) 205.8 205.2 248.2 188.8

Calculate ΔρS° for the following reaction. The S° for each species is shown below the reaction. P₄(g) + 10Cl₂(g) → 4PCl₅(g) S°(J K^-1 mol^-1) 280.0 223.1 364.6

Place the following in order of increasing molar entropy at 298 K. CO₂ C₃H₈ SO

Given the following equation, N₂O(g) + NO₂(g) → 3 NO(g) Δ_rG° = -23.0 kJ mol^-1 Calculate Δ_rG° for the following reaction: 9NO(g) → 3N₂O(g) + 3NO₂(g)

Consider a reaction that has a negative Δ_rH and a negative Δ_rS. Which of the following statements is TRUE?

Calculate Δ_rG° at 298 K using the following information: 4HNO₃(g) + 5N₂H₄(l) → 7N₂(g) + 12H₂O(l) Δ_rG°= ? Δ_fH° (kJ mol^-1) -133.9 50.6 -285.8 S°(J K^-1 mol^-1) 266.9 121.2 191.6 70.0

Calculate Δ_rS° for the following reaction. The S° for each species is shown below the reaction. 4NH₃(g) + 5O₂(g) → 4NO(g) + 6H₂O(g) S°(J K^-1 mol^-1) 192.8 205.2 210.8 188.8