Deck 17: Free Energy and Thermodynamics

Question 1

Which of the following processes has a ΔS > 0?

A)CH₃OH(l)→ CH₃OH(s)
B)N₂(g)+ 3 H₂(g)→ 2 NH₃(g)
C)CH₄(g)+ H₂O(g)→ CO(g)+ 3 H₂(g)
D)Na₂CO₃(s)+ H₂O(g)+ CO₂(g)→ 2 NaHCO₃(s)
E)All of the above processes have a ΔS > 0.

Answer 1

CH₄(g)+ H₂O(g)→ CO(g)+ 3 H₂(g)

Question 2

If ΔG < 0,which of the following statements is true?

A)The reaction is spontaneous.
B)The reaction is not spontaneous.
C)The reaction is at equilibrium.
D)Not enough information is given.

Answer 2

The reaction is spontaneous.

Question 3

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

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.

Answer 3

This reaction will be nonspontaneous only at high temperatures.

Question 4

Which of the following processes has a ΔS < 0?

A)Water freezes.
B)Isopropyl alcohol condenses.
C)methanol (g,at 555 K)→ methanol (g,at 400 K)
D)carbon dioxide(g)→ carbon dioxide(s)
E)All of the above processes have a ΔS < 0.

Question 5

Which of the following statements is true?

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 6

Consider the following reaction at constant P.Use the information here to determine the value of ΔS_surr 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

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

Question 7

If ΔG > 0,which of the following statements is true?

A)The reaction is spontaneous.
B)The reaction is not spontaneous.
C)The reaction is at equilibrium.
D)Not enough information is given.

Question 8

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

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.

Question 9

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

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

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

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.

Question 11

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

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.

Question 12

Which of the following relationships is correct at constant T and P?

A)ΔG is proportional to -ΔS_univ.
B)ΔG > 0 represents a spontaneous process.
C)ΔG > 0 represents an increase in kinetic energy.
D)ΔG < 0 represents a nonspontaneous process.
E)All of the above are correct.

Question 13

Consider the following reaction at constant P.Use the information here to determine the value of ΔS_surr at 398 K.Predict whether or not this reaction will be spontaneous at this temperature.
4 NH₃(g)+ 3 O₂(g)→ 2 N₂(g)+ 6 H₂O(g)ΔH = -1267 kJ

A)ΔS_surr = +12.67 kJ/K,reaction is not spontaneous
B)ΔS_surr = -12.67 kJ/K,reaction is spontaneous
C)ΔS_surr = +50.4 kJ/K,reaction is not spontaneous
D)ΔS_surr = +3.18 kJ/K,reaction is spontaneous
E)ΔS_surr = -3.18 kJ/K,it is not possible to predict the spontaneity of this reaction without more information.

Question 14

Which of the following processes has a ΔS > 0?

A)2 NH₃(g)+ CO₂(g)→ NH₂CONH₂(aq)+ H₂O(l)
B)Lithium fluoride forms from its elements.
C)2 HBr(g)→ H₂(g)+ Br₂(l)
D)Sodium chloride dissolves in pure water.
E)All of the above processes have a DS > 0.

Question 15

Identify the change in state that does not have an increase in entropy.

A)water freezing
B)water boiling
C)ice melting
D)dry ice subliming
E)water evaporating

Question 16

Identify the change in state where ΔS decreases.

A)solid to liquid
B)liquid to gas
C)solid to gas
D)gas to solid

Question 17

Which of the following statements is true?

A)There is a "heat tax" for every energy transaction.
B)A spontaneous reaction is always a fast reaction.
C)The entropy of a system always decreases for a spontaneous process.
D)Perpetual motion machines are a possibility in the near future.
E)None of the above are true.

Question 18

Consider the following reaction at constant P.Use the information here to determine the value of ΔS_surr at 298 K.Predict whether or not this reaction will be spontaneous at this temperature.
N₂(g)+ 2 O₂(g)→ 2 NO₂(g)ΔH = +66.4 kJ

A)ΔS_surr = +223 J/K,reaction is spontaneous
B)ΔS_surr = -223 J/K,reaction is not spontaneous
C)ΔS_surr = -66.4 J/K,reaction is spontaneous
D)ΔS_surr = +66.4 kJ/K,reaction is not spontaneous
E)ΔS_surr = -66.4 J/K,it is not possible to predict the spontaneity of this reaction without more information.

Question 19

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

A)6.762 × 10³ K
B)158.7 K
C)298 K
D)This reaction is nonspontaneous at all temperatures.
E)This reaction is spontaneous at all temperatures.

Question 20

Above what temperature does the following reaction become nonspontaneous?
FeO(s)+ CO(g)→ CO₂(g)+ Fe(s)ΔH = -11.0 kJ;ΔS = -17.4 J/K

A)632 K
B)298 K
C)191 K
D)This reaction is nonspontaneous at all temperatures.
E)This reaction is spontaneous at all temperatures.

Question 21

Place the following in order of increasing standard molar entropy.
H₂O(l)H₂O(g)H₂O(s)

A)H₂O(g)< H₂O(l)< H₂O(s)
B)H₂O(s)< H₂O(l)< H₂O(g)
C)H₂O(g)< H₂O(s)< H₂O(l)
D)H₂O(l)< H₂O(s)< H₂O(g)
E)H₂O(s)< H₂O(g)< H₂O(l)

Question 22

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

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

Question 23

Estimate ΔG°_rxn for the following reaction at 387 K.
HCN(g)+ 2 H₂(g)→ CH₃NH₂(g)ΔH° = -158.0 kJ;ΔS° = -219.9 J/K

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

Question 24

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

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

Question 25

Place the following in order of increasing molar entropy at 298 K.
NO CO SO

A)NO < CO < SO
B)SO < CO < NO
C)SO < NO < CO
D)CO < SO < NO
E)CO < NO < SO

Question 26

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

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

Question 27

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

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

Question 28

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

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

Question 29

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

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)

Question 30

Calculate ΔS°_rxn for the following reaction.The S° for each species is shown below the reaction.
N₂H₄(l)+ H₂(g)→ 2 NH₃(g)
S° (J/mol^∙K)121.2 130.7 192.8

A)+133.7 J/K
B)-59.1 J/K
C)+118.2 J/K
D)-202.3 J/K
E)+178.9 J/K

Question 31

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

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

Question 32

Which of the following statements is true?

A)Entropy is an extensive property.
B)Entropy is not temperature dependent.
C)Exothermic processes decrease the entropy of the surroundings.
D)ΔS_universe is always greater than zero for a nonspontaneous process.
E)None of the above are true.

Question 33

Below what temperature does the following reaction become nonspontaneous?
2 HNO₃(aq)+ NO(g)→ 3 NO₂(g)+ H₂O(l)
ΔH = +136.5 kJ;ΔS = +287.5 J/K

A)39.2 K
B)151 K
C)475 K
D)This reaction is nonspontaneous at all temperatures.
E)This reaction is spontaneous at all temperatures.

Question 34

Calculate ?S°_rxn for the following reaction.The S° for each species is shown below the reaction.
C₂H₂(g)+ H₂(g)? C₂H₄(g)
S°(J/mol?K)200.9 130.7 219.3

A)+112.3 J/K
B)+550.9 J/K
C)-112.3 J/K
D)+337.1 J/K
E)-550.9 J/K

Question 35

Identify the compound that is not an allotrope of carbon.

A)diamond
B)dry ice
C)graphite
D)charcoal
E)buckyball

Question 36

Place the following in order of decreasing molar entropy at 298 K.
H₂ Cl₂ F₂

A)H₂ > Cl₂ > F₂
B)Cl₂ > H₂ > F₂
C)F₂ > Cl₂ > H₂
D)H₂ > F₂ > Cl₂
E)Cl₂ > F₂ > H₂

Question 37

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

A)CO₂ < C₃H₈ < SO
B)C₃H₈ < CO₂ < SO
C)SO < CO₂ < C₃H₈
D)C₃H₈ < SO < CO₂
E)CO₂ < SO < C₃H₈

Question 38

Estimate ΔG°_rxn for the following reaction at 775 K.
2 Hg(g)+ O₂(g)→ 2 HgO(s)ΔH° = -304.2 kJ;ΔS° = -414.2 J/K

A)-625 kJ
B)-181 kJ
C)+17 kJ
D)+321 kJ
E)-110 kJ

Question 39

Give the name of the reaction that achieves the theoretical limits with respect to free energy in thermodynamics.

A)reversible reaction
B)forward reaction
C)reverse reaction
D)equilibrium reaction
E)STP reaction

Question 40

Calculate ΔS°_rxn for the following reaction.The S° for each species is shown below the reaction.
C₂H₂(g)+ 2 H₂(g)→ C₂H₆(g)
S°(J/mol^∙K)200.9 130.7 229.2

A)+303.3 J/K
B)+560.8 J/K
C)-102.4 J/K
D)-233.1 J/K
E)229.2 J/K

Question 41

Use Hess's law to calculate ΔG°_rxn using the following information.
CO(g)→ C(s)+ 1/2 O₂(g)ΔG°_rxn = ?
CO₂(g)→ C(s)+ O₂(g)ΔG°_rxn = +394.4 kJ
CO(g)+ 1/2 O₂(g)→ CO₂(g)ΔG°_rxn = -257.2 kJ

A)-60.0 kJ
B)+651.6 kJ
C)-265.8 kJ
D)+137.2 kJ
E)+523.0 kJ

Question 42

Choose the statement below that is true.

A)K > 1,ΔG°_rxn is positive
B)K < 1,ΔG°_rxn is negative
C)ΔG°_rxn = 0 at equilibrium
D)ΔG_rxn = 0 at equilibrium
E)None of the above statements are true.

Question 43

Calculate the ΔG°_rxn using the following information.
2 HNO₃(aq)+ NO(g)→ 3 NO₂(g)+ H₂O(l)ΔG°_rxn = ?
ΔH°_f (kJ/mol)-207.0 91.3 33.2 -285.8
S°(J/mol^∙K)46.0 210.8 240.1 70.0

A)-151 kJ
B)-85.5 kJ
C)+50.8 kJ
D)+222 kJ
E)-186 kJ

Question 44

Calculate ΔG_rxn at 298 K under the conditions shown below for the following reaction.
2 Hg(g)+ O₂(g)→ 2 HgO(s)ΔG° = -180.8 kJ
P(Hg)= 0.025 atm,P(O₂)= 0.037 atm

A)+207 kJ
B)-154.4 kJ
C)-26.5 kJ
D)-164 kJ
E)+60.7 kJ

Question 45

Calculate ΔG_rxn at 298 K under the conditions shown below for the following reaction.
SO₃(g)+ H₂O(g)→ H₂SO₄(l)ΔG°= -90.5 kJ
P(SO₃)= 0.20 atm,P(H₂O)= 0.88 atm

A)+15.9 kJ
B)-90.5 kJ
C)+51.4 kJ
D)-86.2 kJ
E)-30.4 kJ

Question 46

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

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

Question 47

Determine ΔG°_rxn using the following information.
CaCO₃(s)→ CaO(s)+ CO₂(g)ΔH° = +179.2 kJ;ΔS° = +160.2 J/K

A)-607.0 kJ
B)+112 .0 kJ
C)-89.3 kJ
D)+131.4 kJ
E)+228.1 kJ

Question 48

Calculate ΔG_rxn at 298 K under the conditions shown below for the following reaction.
CaCO₃(s)→ CaO(s)+ CO₂(g)ΔG° = +131.1 kJ
P(CO₂)= 0.033 atm

A)-49.3 kJ
B)-8.32 kJ
C)+122.6 kJ
D)+39.7 kJ
E)+43.3 kJ

Question 49

Determine ΔG°_rxn using the following information.
FeO(s)+ CO(g)→ Fe(s)+ CO₂(g)ΔH° = -11.0 kJ;ΔS° = -17.4 J/K

A)+191.0 kJ
B)-5.8 kJ
C)+1.6 kJ
D)-6.4 kJ
E)+89.5 kJ

Question 50

Calculate the ΔG°_rxn using the following information.
4 HNO₃(g)+ 5 N₂H₄(l)→ 7 N₂(g)+ 12 H₂O(l)ΔG°_rxn = ?
ΔH°_f (kJ/mol)-133.9 50.6 -285.8
S°(J/mol^∙K)266.9 121.2 191.6 70.0

A)+4.90 × 10³ kJ
B)+3.90 × 10³ kJ
C)-2.04 × 10³ kJ
D)-3.15 × 10³ kJ
E)-3.298 × 10³ kJ

Question 51

Use Hess's law to calculate ΔG°_rxn using the following information.
NO(g)+ O(g)→ NO₂(g)ΔG°_rxn = ?
2 O₃(g)→ 3 O₂(g)ΔG°_rxn = +489.6 kJ
O₂(g)→ 2 O(g)ΔG°_rxn = +463.4 kJ
NO(g)+ O₃(g)→ NO₂(g)+ O₂(g)ΔG°_rxn = -199.5 kJ

A)+753.5 kJ
B)+277.0 kJ
C)-676.0 kJ
D)-1152.5 kJ
E)-225.7 kJ

Question 52

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

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

Question 53

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

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

Question 54

Calculate ΔG_rxn at 298 K under the conditions shown below for the following reaction.
Fe₂O₃(s)+ 3 CO(g)→ 2 Fe(s)+ 3 CO₂(g)ΔG° = -28.0 kJ
P(CO)= 1.4 atm,P(CO₂)= 2.1 atm

A)+31.0 kJ
B)+2.99 kJ
C)-30.7 kJ
D)+17.5 kJ
E)-25.0 kJ

Question 55

Choose the statement below that is true.

A)If K < 1,the reaction is spontaneous in the reverse direction.
B)If K < 1,the reaction is spontaneous in the forward direction.
C)If K < 1,the reaction is at equilibrium.
D)Not enough information is given.

Question 56

Determine ΔG°_rxn using the following information.
H₂(g)+ CO(g)→ CH₂O(g)ΔH° = +1.9 kJ;ΔS° = -109.6 J/K

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

Question 57

Calculate the ΔG°_rxn using the following information.
2 H₂S(g)+ 3 O₂(g)→ 2 SO₂(g)+ 2 H₂O(g)ΔG°_rxn = ?
ΔH°_f (kJ/mol)-20.6 296.8 -241.8
S°(J/mol^∙K)205.8 205.248.2 188.8

A)+196.8 kJ
B)+108.2 kJ
C)-466.1 kJ
D)+676.2 kJ
E)-147.1 kJ

Question 58

Which of the following is not true for ΔG_rxn?

A)If ΔG°_rxn > 0,the reaction is spontaneous in the forward direction.
B)If Q = 1,then ΔG_rxn = ΔG°_rxn.
C)If ΔG°_rxn = 0,the reaction is spontaneous in the reverse direction.
D)If ΔG°_rxn > 0,the reaction is spontaneous in the reverse direction.
E)Under equilibrium conditions,ΔG_rxn = 0.

Question 59

Calculate ΔG_rxn at 298 K under the conditions shown below for the following reaction.
3 O₂(g)→ 2 O₃(g)ΔG° = +326 kJ
P(O₂)= 0.41 atm,P(O₃)= 5.2 atm

A)+341 kJ
B)+17.8 kJ
C)+332 kJ
D)-47.4 kJ
E)-109 kJ

Question 60

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

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

Question 61

Why can endothermic reactions be spontaneous?

Question 62

Why is heating your home with gas more efficient than heating it with electricity?

Question 63

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

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

Question 64

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

Question 65

Define the second law of thermodynamics.

Question 66

Match the following.
Q = K

A)ΔG < 0
B)standard state
C)ΔG > 0
D)ΔG < ΔG°
E)equilibrium
F)K = 0
G)ΔG > ΔG°

Question 67

Determine the equilibrium constant for the following reaction at 655 K.
HCN(g)+ 2 H₂(g)→ CH₃NH₂(g)ΔH° = -158 kJ;ΔS°= -219.9 J/K

A)3.99 × 10¹²
B)13.0
C)2.51 × 10^-13
D)3.26 × 10^-12
E)3.07 × 10¹¹

Question 68

Match the following.
Q < K

A)ΔG < 0
B)standard state
C)ΔG > 0
D)ΔG < ΔG°
E)equilibrium
F)K = 0
G)ΔG > ΔG°

Question 69

Why can't we say that a spontaneous reaction is a fast reaction?

Question 70

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

Question 71

Determine the equilibrium constant for the following reaction at 298 K.
Cl(g)+ O₃(g)→ ClO(g)+ O₂(g)ΔG° = -34.5 kJ

A)5.66 × 10⁵
B)0.986
C)8.96 × 10^-7
D)4.98 × 10^-4
E)1.12 × 10⁶

Question 72

What is "free" energy? Give a fictitious example.

Question 73

Match the following.
Q = 1

A)ΔG < 0
B)standard state
C)ΔG > 0
D)ΔG < ΔG°
E)equilibrium
F)K = 0
G)ΔG > ΔG°

Question 74

Match the following.
Q > 1

A)ΔG < 0
B)standard state
C)ΔG > 0
D)ΔG < ΔG°
E)equilibrium
F)K = 0
G)ΔG > ΔG°

Question 75

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

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 76

Match the following.
Q > K

A)ΔG < 0
B)standard state
C)ΔG > 0
D)ΔG < ΔG°
E)equilibrium
F)K = 0
G)ΔG > ΔG°

Question 77

Use the free energies of formation given below to calculate the equilibrium constant (K)for the following reaction at 298 K.
2 HNO₃(aq)+ NO(g)→ 3 NO₂(g)+ H₂O(l)K = ?
ΔG°_f (kJ/mol)-110.9 87.6 51.3 -237.1

A)8.71 × 10⁸
B)0.980
C)1.15 × 10^-9
D)1.02
E)5.11 × 10^-4

Question 78

Determine the equilibrium constant for the following reaction at 549 K.
CH₂O(g)+ 2 H₂(g)→ CH₄(g)+ H₂O(g)
ΔH° = -94.9 kJ;ΔS° = -224.2 J/K

A)481
B)1.07 × 10⁹
C)2.08 × 10^-3
D)9.35 × 10^-10
E)1.94 × 10^-12

Question 79

Match the following.
Q < 1

A)ΔG < 0
B)standard state
C)ΔG > 0
D)ΔG < ΔG°
E)equilibrium
F)K = 0
G)ΔG > ΔG°

Question 80

Determine the equilibrium constant for the following reaction at 298 K.
SO₃(g)+ H₂O(g)→ H₂SO₄(l)ΔG° = -90.5 kJ

A)1.37 × 10^-16
B)4.78 × 10¹¹
C)9.11 × 10^-8
D)7.31 × 10¹⁵
E)0.964