Question 1

Consider the equilibrium that exists between Fe2+ and Fe3+ ions in solution.The extra electron originally on one Fe2+ ion can be transferred to an Fe3+ ion.This amounts to no net reaction because iron(II)  becomes iron(III)  and iron(III)  becomes iron(II) .Which below about this equilibrium is true?

Accepted Answer

A)  There is no activation energy for this reaction.
B)  K = 1.
C)  K =0.
D)  There is no net reaction, so there is no value for K.
E)  The concentrations of iron(II)  and iron(III)  change because of the electron transfer.

Question 2

For a particular hypothetical reaction, 2A(aq)  +B(aq)   →\rightarrow→  C(aq) , the value of  Δ\DeltaΔ G °\degree° is 2.50 * 102 kJ/mol.What is the value of  Δ\DeltaΔ G for this reaction at 298 K when [A] = 0.600 M, [B]= 0.100 M, and [C]= 4.00 *10-3 M ?

Accepted Answer

A)  2.48 * 102 kJ/mol
B)  2.45 * 102 kJ/mol
C)  2.78* 103 kJ/mol
D)  2.50 *102 kJ/mol
E)  2.55* 102 kJ/mol

Question 3

The  Δ\DeltaΔ G  °\degree° f of atomic oxygen is 230.1 kJ/mol.Determine the equilibrium constant for the following reaction at standard thermodynamic conditions: O2 (g)  ⇄ 2 O(g)

Accepted Answer

A)  4.7 * 10-41
B)  2.3 * 10-61
C)  2.1 *10-81
D)  2.1*1040
E)  4.5* 1080

Question 4

The forward rate constant, kf, and reverse rate constant, kr, for a chemical reaction are not equal.Which statement below must be true?

Accepted Answer

A)  The reaction will be unable to achieve equilibrium.
B)  kf and kr will become equal as equilibrium is approached owing to concentration changes.
C)  kf and kr will become equal as equilibrium is approached owing to temperature changes.
D)  kf and kr will remain unequal, but the rates will become equal owing to concentration changes.
E)  kf and kr will remain unequal, but the rates will become equal owing to temperature changes.

Question 5

Under what conditions are the values of Kc and Kp for a given gas-phase equilibrium the same?

Accepted Answer

A)  There is no change in the moles of gas in the reaction.
B)  There is no change in the temperature during the reaction.
C)  The coefficients of the reactants and products are the same.
D)  The pressure remains constant.
E)  Either Kc or Kp = 1.

Question 6

Which of the following occurs when products are removed from a chemical reaction in solution or the gas phase at equilibrium?

Accepted Answer

A)  Q increases and the equilibrium shifts to produce more products.
B)  Q increases and the equilibrium shifts to produce more reactants.
C)  Q decreases and the equilibrium shifts to produce more products.
D)  Q decreases and the equilibrium shifts to produce more reactants.
E)  Q is unchanged by the addition of reactants.

Question 7

One mole of solid ammonium carbamate (NH4CO2NH2) decomposes to form gaseous ammonia NH3) and carbon dioxide.Write an expression for the equilibrium constant Kc) for this reaction.

Accepted Answer

K_c= [NH₃]²[CO₂]

Question 8

For an equilibrium reaction with K = 1.2 * 108, the forward rate constant was found to be 3.5*105.What is the value of the reverse rate constant?

Accepted Answer

A)  3.5 *105
B)  3.4*102
C)  4.2 * 1013
D)  6.0 * 10-
E)  2.9 * 10-3

Question 9

If the temperature of an endothermic reaction at equilibrium could be increased instantaneously, what would be the instantaneous effect on Q and K before equilibrium was again achieved?

Accepted Answer

A)  Q would increase and K would stay the same.
B)  Q would decrease and K would stay the same.
C)  Q would stay the same and K would increase.
D)  Q would stay the same and K would decrease.
E)  Both Q and K would stay the same.

Question 10

Which statement below, if any, is NOT a perturbation or stress to the equilibrium position of an endothermic chemical reaction that involves one or more gases?

Accepted Answer

A)  adding reactants to a gas or solution reaction
B)  removing products from a gas or solution reaction
C)  decreasing the temperature
D)  increasing pressure by adding an inert gas to a reaction in the gas phase
E)  All of the above are perturbations to chemical equilibrium.

Question 11

When plotting ln K vs.1/T, a linear relationship is obtained

Accepted Answer

A)  with a slope of - Δ\DeltaΔ H  °\degree° /R and an intercept of - Δ\DeltaΔ S  °\degree° /R.
B)  with a slope of - Δ\DeltaΔ H  °\degree° /R and an intercept of - Δ\DeltaΔ S  °\degree° /R 
C)  with a slope of - Δ\DeltaΔ H  °\degree° /R and an intercept of + Δ\DeltaΔ S  °\degree° /R..
D)  with a slope of + Δ\DeltaΔ H  °\degree° /R and an intercept of - Δ\DeltaΔ S  °\degree° /R.
E)  never, as logarithmic relationships are intrinsically nonlinear.  A

Question 12

If Q for a reaction is greater than K, the reaction will proceed in the _______ direction.If Q for a reaction is less than K, the reaction will proceed in the _______ direction.If Q for a reaction is equal to K, the reaction is _______ .

Accepted Answer

reverse; f...

Question 13

The following reactions at 1000.0 K have the following Kp values: H2 (g)  + CL2 (g)  ⇄ 2 HCl(g)  Kp = 3.8 * 104
H2 (g)  + Br2 (g)  ⇄ 2 HBr(g) )  Kp =5.1 *108
Br2 (g)  + CL2 (g)  ⇄ 2 Br Cl(g)  Kp = 0.20
What is Kp for the reaction HCl(g)  + HBr(g)  ⇄ BrCl(g)  + H2(g)  at 1000.0 K?

Accepted Answer

A)  5.1 *10-7
B)  1.0 *10-7
C)  5.2*10-15
D)  0.45
E)  1.0 *10-14

Question 14

Equilibrium constants for two reactions are known as follows: 
A + B ⇄ C $\quad$K1
D +E ⇄ 2 C $\quad$K2
What is the expression for the equilibrium constant for the reaction in which A and B form one mole each of D and E?

Accepted Answer

K =K₁²/K₂

Question 15

The reaction of hydrogen gas with chlorine gas, H2 (g)  + CL2 (g)  ⇄ 2 HCl(g) , has a Kp value of 0.500.If 0.250 atm of both H2 and Cl2 are placed in a closed vessel and allowed to come to equilibrium, what is the equilibrium partial pressure of HCl(g) ?

Accepted Answer

A)  0.250 atm
B)  0.104 atm
C)  0.0653 atm
D)  0.177 atm
E)  0.131 atm

Question 16

For the chemical equilibrium aA + bB ⇄ cC, the value of the equilibrium constant K is 10.What is the value of the equilibrium constant for the reaction cC ⇄ aA + bB?

Accepted Answer

A)  0.1
B)  10
C)  1
D)  100
E)  (-10)

Question 17

Consider the equilibrium CL2 (g)  + 2 NO(g)  ⇄ 2 NOCl(g) .When 2.000 M NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium concentration of Cl2 is 0.979 M.Calculate Kc.

Accepted Answer

A)  45.6
B)  15.2
C)  0.938
D)  2130
E)  4.70 * 10-4

Question 18

Consider a reaction at a point in which the difference in free energy between the reactants and products is twice the standard free energy change for the reaction.What expression would allow you to calculate the reaction quotient under these conditions, and what would be required for the reaction to be spontaneous?

Accepted Answer

Q = e^{+G /RT}

Question 19

Consider the equilibrium A +B ⇄ C.What is significant about the reaction quotient when [B] = [C]?

Accepted Answer

A)  only that [B] = [C]
B)  [A] = [B]= [C]
C)  [B] = [C] = K
D)  [A]=K
E)  The reaction must run in the forward direction.

Question 20

For the equilibrium CH4 (g)  +2 H2 S(g)  ⇆ CS2 (g)  +4 H2 (g) , the concentrations at equilibrium are [CH4] = 0.3322 M, [H2S] = 0.6644 M, [CS2] =0.0678 M, and [H2] =0.2712 M at 1400.0 K.Calculate Kc.

Accepted Answer

A)  0.167
B)  2.50 * 10-3
C)  4.00 * 102
D)  6.00
E)  0.694

Exam 14: Chemical Equilibrium Equal but Opposite Reaction Rates

Correct Answer
verified

For a particular hypothetical reaction, 2A(aq) +B(aq) $\rightarrow$ C(aq) , the value of $\Delta$ G $\degree$ is 2.50 * 10² kJ/mol.What is the value of $\Delta$ G for this reaction at 298 K when [A] = 0.600 M, [B]= 0.100 M, and [C]= 4.00 *10^-3 M ?

Correct Answer
verified

The $\Delta$ G $\degree$ _f of atomic oxygen is 230.1 kJ/mol.Determine the equilibrium constant for the following reaction at standard thermodynamic conditions: O₂ (g) ⇄ 2 O(g)

Correct Answer
verified

The forward rate constant, k_f, and reverse rate constant, k_r, for a chemical reaction are not equal.Which statement below must be true?

Correct Answer
verified

Under what conditions are the values of K_c and K_p for a given gas-phase equilibrium the same?

Correct Answer
verified

Which of the following occurs when products are removed from a chemical reaction in solution or the gas phase at equilibrium?

Correct Answer
verified

One mole of solid ammonium carbamate (NH₄CO₂NH₂) decomposes to form gaseous ammonia NH₃) and carbon dioxide.Write an expression for the equilibrium constant K_c) for this reaction.

Correct Answer
verified
K_c= [NH₃]²[CO₂]

For an equilibrium reaction with K = 1.2 * 10⁸, the forward rate constant was found to be 3.5*10⁵.What is the value of the reverse rate constant?

Correct Answer
verified

If the temperature of an endothermic reaction at equilibrium could be increased instantaneously, what would be the instantaneous effect on Q and K before equilibrium was again achieved?

Correct Answer
verified

Which statement below, if any, is NOT a perturbation or stress to the equilibrium position of an endothermic chemical reaction that involves one or more gases?

Correct Answer
verified

When plotting ln K vs.1/T, a linear relationship is obtained

Correct Answer
verified
A

If Q for a reaction is greater than K, the reaction will proceed in the ___ direction.If Q for a reaction is less than K, the reaction will proceed in the _ direction.If Q for a reaction is equal to K, the reaction is _____ .

Correct Answer
verified
reverse; f...
View Answer

The following reactions at 1000.0 K have the following K_p values: H₂ (g) + CL₂ (g) ⇄ 2 HCl(g) K_p = 3.8 * 10⁴ H₂ (g) + Br₂ (g) ⇄ 2 HBr(g) ) K_p =5.1 *10⁸ Br₂ (g) + CL₂ (g) ⇄ 2 Br Cl(g) K_p = 0.20 What is K_p for the reaction HCl(g) + HBr(g) ⇄ BrCl(g) + H₂(g) at 1000.0 K?

Correct Answer
verified

Equilibrium constants for two reactions are known as follows: A + B ⇄ C $\quad$ K₁ D +E ⇄ 2 C $\quad$ K₂ What is the expression for the equilibrium constant for the reaction in which A and B form one mole each of D and E?

Correct Answer
verified
K =K₁²/K₂

The reaction of hydrogen gas with chlorine gas, H₂ (g) + CL₂ (g) ⇄ 2 HCl(g) , has a K_p value of 0.500.If 0.250 atm of both H₂ and Cl₂ are placed in a closed vessel and allowed to come to equilibrium, what is the equilibrium partial pressure of HCl(g) ?

Correct Answer
verified

For the chemical equilibrium aA + bB ⇄ cC, the value of the equilibrium constant K is 10.What is the value of the equilibrium constant for the reaction cC ⇄ aA + bB?

Correct Answer
verified

Consider the equilibrium CL₂ (g) + 2 NO(g) ⇄ 2 NOCl(g) .When 2.000 M NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium concentration of Cl₂ is 0.979 M.Calculate K_c.

Correct Answer
verified

Correct Answer
verified
Q = e^{+G /RTView Answer}

Consider the equilibrium A +B ⇄ C.What is significant about the reaction quotient when [B] = [C]?

Correct Answer
verified

For the equilibrium CH₄ (g) +2 H₂ S(g) ⇆ CS₂ (g) +4 H₂ (g) , the concentrations at equilibrium are [CH₄] = 0.3322 M, [H₂S] = 0.6644 M, [CS₂] =0.0678 M, and [H₂] =0.2712 M at 1400.0 K.Calculate K_c.

Correct Answer
verified

Exam 14: Chemical Equilibrium Equal but Opposite Reaction Rates

Consider the equilibrium that exists between Fe2+ and Fe3+ ions in solution.The extra electron originally on one Fe2+ ion can be transferred to an Fe3+ ion.This amounts to no net reaction because iron(II) becomes iron(III) and iron(III) becomes iron(II) .Which below about this equilibrium is true?

Correct AnswerverifiedShow Answer

For a particular hypothetical reaction, 2A(aq) +B(aq) →\rightarrow→ C(aq) , the value of Δ\DeltaΔ G °\degree° is 2.50 * 102 kJ/mol.What is the value of Δ\DeltaΔ G for this reaction at 298 K when [A] = 0.600 M, [B]= 0.100 M, and [C]= 4.00 *10-3 M ?

Correct AnswerverifiedShow Answer

The Δ\DeltaΔ G °\degree° f of atomic oxygen is 230.1 kJ/mol.Determine the equilibrium constant for the following reaction at standard thermodynamic conditions: O2 (g) ⇄ 2 O(g)

Correct AnswerverifiedShow Answer

The forward rate constant, kf, and reverse rate constant, kr, for a chemical reaction are not equal.Which statement below must be true?

Correct AnswerverifiedShow Answer

Under what conditions are the values of Kc and Kp for a given gas-phase equilibrium the same?

Correct AnswerverifiedShow Answer

Which of the following occurs when products are removed from a chemical reaction in solution or the gas phase at equilibrium?

Correct AnswerverifiedShow Answer

One mole of solid ammonium carbamate (NH4CO2NH2) decomposes to form gaseous ammonia NH3) and carbon dioxide.Write an expression for the equilibrium constant Kc) for this reaction.

Correct AnswerverifiedKc= [NH3]2[CO2]

For an equilibrium reaction with K = 1.2 * 108, the forward rate constant was found to be 3.5*105.What is the value of the reverse rate constant?

Correct AnswerverifiedShow Answer

If the temperature of an endothermic reaction at equilibrium could be increased instantaneously, what would be the instantaneous effect on Q and K before equilibrium was again achieved?

Correct AnswerverifiedShow Answer

Which statement below, if any, is NOT a perturbation or stress to the equilibrium position of an endothermic chemical reaction that involves one or more gases?

Correct AnswerverifiedShow Answer

When plotting ln K vs.1/T, a linear relationship is obtained

Correct AnswerverifiedA

If Q for a reaction is greater than K, the reaction will proceed in the _______ direction.If Q for a reaction is less than K, the reaction will proceed in the _______ direction.If Q for a reaction is equal to K, the reaction is _______ .

Correct Answerverifiedreverse; f...View AnswerShow Answer

The following reactions at 1000.0 K have the following Kp values: H2 (g) + CL2 (g) ⇄ 2 HCl(g) Kp = 3.8 * 104 H2 (g) + Br2 (g) ⇄ 2 HBr(g) ) Kp =5.1 *108 Br2 (g) + CL2 (g) ⇄ 2 Br Cl(g) Kp = 0.20 What is Kp for the reaction HCl(g) + HBr(g) ⇄ BrCl(g) + H2(g) at 1000.0 K?

Correct AnswerverifiedShow Answer

Equilibrium constants for two reactions are known as follows: A + B ⇄ C \quad K1 D +E ⇄ 2 C \quad K2 What is the expression for the equilibrium constant for the reaction in which A and B form one mole each of D and E?

Correct AnswerverifiedK =K12/K2

The reaction of hydrogen gas with chlorine gas, H2 (g) + CL2 (g) ⇄ 2 HCl(g) , has a Kp value of 0.500.If 0.250 atm of both H2 and Cl2 are placed in a closed vessel and allowed to come to equilibrium, what is the equilibrium partial pressure of HCl(g) ?

Correct AnswerverifiedShow Answer

For the chemical equilibrium aA + bB ⇄ cC, the value of the equilibrium constant K is 10.What is the value of the equilibrium constant for the reaction cC ⇄ aA + bB?

Correct AnswerverifiedShow Answer

Consider the equilibrium CL2 (g) + 2 NO(g) ⇄ 2 NOCl(g) .When 2.000 M NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium concentration of Cl2 is 0.979 M.Calculate Kc.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedQ = e+G /RTView AnswerShow Answer

Consider the equilibrium A +B ⇄ C.What is significant about the reaction quotient when [B] = [C]?

Correct AnswerverifiedShow Answer

For the equilibrium CH4 (g) +2 H2 S(g) ⇆ CS2 (g) +4 H2 (g) , the concentrations at equilibrium are [CH4] = 0.3322 M, [H2S] = 0.6644 M, [CS2] =0.0678 M, and [H2] =0.2712 M at 1400.0 K.Calculate Kc.

Correct AnswerverifiedShow Answer

Correct Answer
verified

For a particular hypothetical reaction, 2A(aq) +B(aq) $\rightarrow$ C(aq) , the value of $\Delta$ G $\degree$ is 2.50 * 10² kJ/mol.What is the value of $\Delta$ G for this reaction at 298 K when [A] = 0.600 M, [B]= 0.100 M, and [C]= 4.00 *10^-3 M ?

Correct Answer
verified

The $\Delta$ G $\degree$ _f of atomic oxygen is 230.1 kJ/mol.Determine the equilibrium constant for the following reaction at standard thermodynamic conditions: O₂ (g) ⇄ 2 O(g)

Correct Answer
verified

The forward rate constant, k_f, and reverse rate constant, k_r, for a chemical reaction are not equal.Which statement below must be true?

Correct Answer
verified

Under what conditions are the values of K_c and K_p for a given gas-phase equilibrium the same?

Correct Answer
verified

Correct Answer
verified

One mole of solid ammonium carbamate (NH₄CO₂NH₂) decomposes to form gaseous ammonia NH₃) and carbon dioxide.Write an expression for the equilibrium constant K_c) for this reaction.

Correct Answer
verified
K_c= [NH₃]²[CO₂]

For an equilibrium reaction with K = 1.2 * 10⁸, the forward rate constant was found to be 3.5*10⁵.What is the value of the reverse rate constant?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
A

If Q for a reaction is greater than K, the reaction will proceed in the ___ direction.If Q for a reaction is less than K, the reaction will proceed in the _ direction.If Q for a reaction is equal to K, the reaction is _____ .

Correct Answer
verified
reverse; f...
View Answer

The following reactions at 1000.0 K have the following K_p values: H₂ (g) + CL₂ (g) ⇄ 2 HCl(g) K_p = 3.8 * 10⁴ H₂ (g) + Br₂ (g) ⇄ 2 HBr(g) ) K_p =5.1 *10⁸ Br₂ (g) + CL₂ (g) ⇄ 2 Br Cl(g) K_p = 0.20 What is K_p for the reaction HCl(g) + HBr(g) ⇄ BrCl(g) + H₂(g) at 1000.0 K?

Correct Answer
verified

Equilibrium constants for two reactions are known as follows: A + B ⇄ C $\quad$ K₁ D +E ⇄ 2 C $\quad$ K₂ What is the expression for the equilibrium constant for the reaction in which A and B form one mole each of D and E?

Correct Answer
verified
K =K₁²/K₂

The reaction of hydrogen gas with chlorine gas, H₂ (g) + CL₂ (g) ⇄ 2 HCl(g) , has a K_p value of 0.500.If 0.250 atm of both H₂ and Cl₂ are placed in a closed vessel and allowed to come to equilibrium, what is the equilibrium partial pressure of HCl(g) ?

Correct Answer
verified

Correct Answer
verified

Consider the equilibrium CL₂ (g) + 2 NO(g) ⇄ 2 NOCl(g) .When 2.000 M NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium concentration of Cl₂ is 0.979 M.Calculate K_c.

Correct Answer
verified

Correct Answer
verified
Q = e^{+G /RTView Answer}

Correct Answer
verified

For the equilibrium CH₄ (g) +2 H₂ S(g) ⇆ CS₂ (g) +4 H₂ (g) , the concentrations at equilibrium are [CH₄] = 0.3322 M, [H₂S] = 0.6644 M, [CS₂] =0.0678 M, and [H₂] =0.2712 M at 1400.0 K.Calculate K_c.

Correct Answer
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