Question 1

Calculate the ΔG°rxn using the following information.
4 HNO3(g)+ 5 N2H4(l)→ 7 N2(g)+ 12 H2O(l)ΔG°rxn = ?
ΔG°f (kJ/mol)-73.5 149.3 -237.1

Accepted Answer

A) -3.298 × 103 kJ 
B) -312.9 kJ 
C) +2.845 × 103 kJ 
D) +110.7 kJ 
E) -954.7 kJ

Question 2

Calculate the ΔG°rxn using the following information.
2 H2S(g)+ 3 O2(g)→ 2 SO2(g)+ 2 H2O(g)ΔG°rxn = ?
ΔG°f (kJ/mol)-33.4 -3300.1 -228.6

Accepted Answer

A) +112.4 kJ 
B) -495.3 kJ 
C) -528.7 kJ 
D) +66.8 kJ 
E) -6990.6 kJ

Question 3

Which of the following reactions will have the largest equilibrium constant (K)at 298 K?

Accepted Answer

A) CaCO3(s)→ CaO(s)+ CO2(g)ΔG° = +131.1 kJ 
B) 2 Hg(g)+ O2(g)→ 2 HgO(s)ΔG° = -180.8 kJ 
C) 3 O2(g)→ 2 O3(g)ΔG° = +326 kJ 
D) Fe2O3(s)+ 3 CO(g)→ 2 Fe(s)+ 3 CO2(g)ΔG° = -28.0 kJ 
E) It is not possible to determine without more information.

Question 4

Match the following.
-Q < 1

Accepted Answer

A) ΔG  0 
D) ΔG  ΔG°

Question 5

Place the following in order of decreasing molar entropy at 298 K.
HCl N2H4 Ar

Accepted Answer

A) Ar > N2H4 > HCl 
B) Ar > HCl > N2H4 
C) N2H4 > Ar > HCl 
D) N2H4 > HCl > Ar 
E) HCl > N2H4 > Ar

Question 6

Estimate ΔG°rxn for the following reaction at 449.0 K.
CH2O(g)+ 2 H2(g)→ CH4(g)+ H2O(g)
ΔH° = -94.9 kJ;ΔS° = -224.2 J/K

Accepted Answer

A) +5.8 kJ 
B) +12.9 kJ 
C) -101 kJ 
D) +2.4 kJ 
E) -4.2 kJ

Question 7

How many microstates are possible in a collection of 2 particles that are present in 2 connected flasks?

Accepted Answer

The answer of How many microstates are possible in a...

Question 8

For a given reaction,ΔH = +35.5 kJ/mol and ΔS = +83.6 J/K-mol.The reaction is spontaneous ________.Assume that ΔH and ΔS do not vary with temperature.

Accepted Answer

A) at T  425 K 
C) at all temperatures 
D) at T > 298 K 
E) at T < 298 K

Question 9

Which of the following processes shows a decrease in entropy of the system?

Accepted Answer

A) 2 NO(g)+ O2(g)→ 2 NO2(g) 
B) COCl2(g)→ CO(g)+ Cl2(g) 
C) CH3OH(l)→ CO(g)+ 2H2(g) 
D) NaClO3(s)→ Na+(aq)+ ClO3-(aq) 
E) None of the above will show a decrease in entropy.

Question 10

Calculate the ΔG°rxn using the following information.
2 HNO3(aq)+ NO(g)→ 3 NO2(g)+ H2O(l)ΔG°rxn = ?
ΔG°f (kJ/mol)-110.9 87.6 51.3 -237.1

Accepted Answer

A) -162.5 kJ 
B) +51.0 kJ 
C) -54.5 kJ 
D) +171.1 kJ 
E) -87.6 kJ

Question 11

Give the standard states for a gas,liquid,solid,and solution.

Accepted Answer

The answer of Give the standard states for a gas,liquid,solid,and...

Question 12

The following reaction at 25°C produces 74.6 kJ of heat and 24.1 kJ of heat is lost to the surroundings.How much energy is available to do work?
C(s)+ 2H2(g)→ CH4(g)

Accepted Answer

A) 98.7 kJ 
B) 24.1 kJ 
C) 50.5 kJ 
D) 74.6 kJ

Question 13

Consider the following reaction at constant P.Use the information here to determine the value of ΔSsurr at 355 K.Predict whether or not this reaction will be spontaneous at this temperature.
2 NO(g)+ O2(g)→ 2 NO2(g)ΔH = -114 kJ

Accepted Answer

A) ΔSsurr = +114 kJ/K,reaction is spontaneous 
B) ΔSsurr = +114 kJ/K,reaction is not spontaneous 
C) ΔSsurr = +321 J/K,reaction is spontaneous 
D) ΔSsurr = -321 J/K,reaction is not spontaneous 
E) ΔSsurr = +321 J/K,it is not possible to predict the spontaneity of this reaction without more information.

Question 14

Determine the equilibrium constant for the following reaction at 498 K.
2 Hg(g)+ O2(g)→ 2 HgO(s)ΔH° = -304.2 kJ;ΔS° = -414.2 J/K

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 15

Place the following in order of decreasing standard molar entropy.
N2O4(g)NO(g)NO2(g)

Accepted Answer

A) N2O4 > NO2 > NO 
B) NO > NO2 > N2O4 
C) N2O4 > NO > NO2 
D) NO > N2O4 > NO2 
E) NO2 > NO > N2O4

Question 16

For a given reaction,ΔH = -19.9 kJ/mol and ΔS = -55.5 J/K-mol.The reaction will have ΔG = 0 at ________ K.Assume that ΔH and ΔS do not vary with temperature.

Accepted Answer

A) 359 
B) 2789 
C) 298 
D) 2.79 
E) 0.359

Question 17

Match the following.
-Q > 1

Accepted Answer

A) ΔG  0 
D) ΔG  ΔG°

Question 18

Use Hess's law to calculate ΔG°rxn using the following information.
ClO(g)+ O3(g)→ Cl(g)+ 2 O2(g)ΔG°rxn = ?
2 O3(g)→ 3 O2(g)ΔG°rxn = +489.6 kJ
Cl(g)+ O3(g)→ ClO(g)+ O2(g)ΔG°rxn = -34.5 kJ

Accepted Answer

A) -472.4 kJ 
B) -210.3 kJ 
C) +455.1 kJ 
D) +262.1 kJ 
E) +524.1 kJ

Question 19

Which of the following statements is true?

Accepted Answer

A) Entropy is not a state function. 
B) Endothermic processes decrease the entropy of the surroundings,at constant T and P. 
C) Endothermic processes are never spontaneous. 
D) Exothermic processes are always spontaneous. 
E) None of the above are true.

Question 20

Consider a reaction that has a positive ΔH and a positive ΔS.Which of the following statements is true?

Accepted Answer

A) This reaction will be spontaneous only at high 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 high temperatures. 
E) It is not possible to determine without more information.

Exam 17: Free Energy and Thermodynamics

Calculate the ΔG°_rxn using the following information. 4 HNO₃(g) + 5 N₂H₄(l) → 7 N₂(g) + 12 H₂O(l) ΔG°_rxn= ? ΔG°_f (kJ/mol) -73.5 149.3 -237.1

Calculate the ΔG°_rxn using the following information. 2 H₂S(g) + 3 O₂(g) → 2 SO₂(g) + 2 H₂O(g) ΔG°_rxn= ? ΔG°_f (kJ/mol) -33.4 -3300.1 -228.6

Which of the following reactions will have the largest equilibrium constant (K) at 298 K?

Match the following. -Q < 1

Place the following in order of decreasing molar entropy at 298 K. HCl N₂H₄ Ar

Estimate ΔG°_rxn for the following reaction at 449.0 K. CH₂O(g) + 2 H₂(g) → CH₄(g) + H₂O(g) ΔH° = -94.9 kJ;ΔS° = -224.2 J/K

How many microstates are possible in a collection of 2 particles that are present in 2 connected flasks?

For a given reaction,ΔH = +35.5 kJ/mol and ΔS = +83.6 J/K-mol.The reaction is spontaneous ________.Assume that ΔH and ΔS do not vary with temperature.

Which of the following processes shows a decrease in entropy of the system?

Calculate the ΔG°_rxn using the following information. 2 HNO₃(aq) + NO(g) → 3 NO₂(g) + H₂O(l) ΔG°_rxn= ? ΔG°_f (kJ/mol) -110.9 87.6 51.3 -237.1

Give the standard states for a gas,liquid,solid,and solution.

The following reaction at 25°C produces 74.6 kJ of heat and 24.1 kJ of heat is lost to the surroundings.How much energy is available to do work? C(s) + 2H₂(g) → CH₄(g)

Consider the following reaction at constant P.Use the information here to determine the value of ΔS_surrat 355 K.Predict whether or not this reaction will be spontaneous at this temperature. 2 NO(g) + O₂(g) → 2 NO₂(g) ΔH = -114 kJ

Determine the equilibrium constant for the following reaction at 498 K. 2 Hg(g) + O₂(g) → 2 HgO(s) ΔH° = -304.2 kJ;ΔS° = -414.2 J/K

Place the following in order of decreasing standard molar entropy. N₂O₄(g) NO(g) NO₂(g)

For a given reaction,ΔH = -19.9 kJ/mol and ΔS = -55.5 J/K-mol.The reaction will have ΔG = 0 at ________ K.Assume that ΔH and ΔS do not vary with temperature.

Match the following. -Q > 1

Use Hess's law to calculate ΔG°_rxn using the following information. ClO(g) + O₃(g) → Cl(g) + 2 O₂(g) ΔG°_rxn= ? 2 O₃(g) → 3 O₂(g) ΔG°_rxn= +489.6 kJ Cl(g) + O₃(g) → ClO(g) + O₂(g) ΔG°_rxn= -34.5 kJ

Which of the following statements is true?

Consider a reaction that has a positive ΔH and a positive ΔS.Which of the following statements is true?

Exam 17: Free Energy and Thermodynamics

Calculate the ΔG°rxn using the following information. 4 HNO3(g) + 5 N2H4(l) → 7 N2(g) + 12 H2O(l) ΔG°rxn = ? ΔG°f (kJ/mol) -73.5 149.3 -237.1

Calculate the ΔG°rxn using the following information. 2 H2S(g) + 3 O2(g) → 2 SO2(g) + 2 H2O(g) ΔG°rxn = ? ΔG°f (kJ/mol) -33.4 -3300.1 -228.6

Which of the following reactions will have the largest equilibrium constant (K) at 298 K?

Match the following. -Q < 1

Place the following in order of decreasing molar entropy at 298 K. HCl N2H4 Ar

Estimate ΔG°rxn for the following reaction at 449.0 K. CH2O(g) + 2 H2(g) → CH4(g) + H2O(g) ΔH° = -94.9 kJ;ΔS° = -224.2 J/K

How many microstates are possible in a collection of 2 particles that are present in 2 connected flasks?

For a given reaction,ΔH = +35.5 kJ/mol and ΔS = +83.6 J/K-mol.The reaction is spontaneous ________.Assume that ΔH and ΔS do not vary with temperature.

Which of the following processes shows a decrease in entropy of the system?

Calculate the ΔG°rxn using the following information. 2 HNO3(aq) + NO(g) → 3 NO2(g) + H2O(l) ΔG°rxn = ? ΔG°f (kJ/mol) -110.9 87.6 51.3 -237.1

Give the standard states for a gas,liquid,solid,and solution.

The following reaction at 25°C produces 74.6 kJ of heat and 24.1 kJ of heat is lost to the surroundings.How much energy is available to do work? C(s) + 2H2(g) → CH4(g)

Consider the following reaction at constant P.Use the information here to determine the value of ΔSsurr at 355 K.Predict whether or not this reaction will be spontaneous at this temperature. 2 NO(g) + O2(g) → 2 NO2(g) ΔH = -114 kJ

Determine the equilibrium constant for the following reaction at 498 K. 2 Hg(g) + O2(g) → 2 HgO(s) ΔH° = -304.2 kJ;ΔS° = -414.2 J/K

Place the following in order of decreasing standard molar entropy. N2O4(g) NO(g) NO2(g)

For a given reaction,ΔH = -19.9 kJ/mol and ΔS = -55.5 J/K-mol.The reaction will have ΔG = 0 at ________ K.Assume that ΔH and ΔS do not vary with temperature.

Match the following. -Q > 1

Use Hess's law to calculate ΔG°rxn using the following information. ClO(g) + O3(g) → Cl(g) + 2 O2(g) ΔG°rxn = ? 2 O3(g) → 3 O2(g) ΔG°rxn = +489.6 kJ Cl(g) + O3(g) → ClO(g) + O2(g) ΔG°rxn = -34.5 kJ

Which of the following statements is true?

Consider a reaction that has a positive ΔH and a positive ΔS.Which of the following statements is true?

Calculate the ΔG°_rxn using the following information. 4 HNO₃(g) + 5 N₂H₄(l) → 7 N₂(g) + 12 H₂O(l) ΔG°_rxn= ? ΔG°_f (kJ/mol) -73.5 149.3 -237.1

Calculate the ΔG°_rxn using the following information. 2 H₂S(g) + 3 O₂(g) → 2 SO₂(g) + 2 H₂O(g) ΔG°_rxn= ? ΔG°_f (kJ/mol) -33.4 -3300.1 -228.6

Place the following in order of decreasing molar entropy at 298 K. HCl N₂H₄ Ar

Estimate ΔG°_rxn for the following reaction at 449.0 K. CH₂O(g) + 2 H₂(g) → CH₄(g) + H₂O(g) ΔH° = -94.9 kJ;ΔS° = -224.2 J/K

Calculate the ΔG°_rxn using the following information. 2 HNO₃(aq) + NO(g) → 3 NO₂(g) + H₂O(l) ΔG°_rxn= ? ΔG°_f (kJ/mol) -110.9 87.6 51.3 -237.1

The following reaction at 25°C produces 74.6 kJ of heat and 24.1 kJ of heat is lost to the surroundings.How much energy is available to do work? C(s) + 2H₂(g) → CH₄(g)

Consider the following reaction at constant P.Use the information here to determine the value of ΔS_surrat 355 K.Predict whether or not this reaction will be spontaneous at this temperature. 2 NO(g) + O₂(g) → 2 NO₂(g) ΔH = -114 kJ

Determine the equilibrium constant for the following reaction at 498 K. 2 Hg(g) + O₂(g) → 2 HgO(s) ΔH° = -304.2 kJ;ΔS° = -414.2 J/K

Place the following in order of decreasing standard molar entropy. N₂O₄(g) NO(g) NO₂(g)

Use Hess's law to calculate ΔG°_rxn using the following information. ClO(g) + O₃(g) → Cl(g) + 2 O₂(g) ΔG°_rxn= ? 2 O₃(g) → 3 O₂(g) ΔG°_rxn= +489.6 kJ Cl(g) + O₃(g) → ClO(g) + O₂(g) ΔG°_rxn= -34.5 kJ