Question 1

For the phase transition H2O2 (l)  ⇄ H2O2 (g)  at 298 K,  Δ\DeltaΔ G  °\degree°  = 14.8 kJ/mol.Calculate  Δ\DeltaΔ G when the partial pressure of hydrogen peroxide in a closed container is 1.00 torr.Will liquid H 2O2 spontaneously evaporate, or will vapor phase H2O2 spontaneously condense?

Accepted Answer

A)  ( Δ\DeltaΔ G =16.4 kJ/mol; liquid H2O2 will evaporate.) 
B)  ( Δ\DeltaΔ G =1.6 kJ/mol; liquid H2O2 will evaporate.) 
C)  ( Δ\DeltaΔ G = 14.8 kJ/mol; vapor-phase H2O2 will condense.) 
D)  ( Δ\DeltaΔ G = 8.17 kJ/mol; vapor-phase H2O2 will condense.) 
E)  ( Δ\DeltaΔ G = 0 kJ/mol; the system is at equilibrium.)  F) A) and E)
G) C) and D)

Question 2

Which statement below concerning a chemical reaction at equilibrium is true?

Accepted Answer

A)  Only the forward reaction stops.
B)  Only the reverse reaction stops.
C)  Both the forward and reverse reactions stop.
D)  The rate constants for the forward and reverse reactions are equal.
E)  The rates of the forward and reverse reactions are equal.F) D) and E)
G) A) and B)

Question 3

The equilibrium constants for the two reactions are known: 
M m++ 4 L- ⇄ [ML4]m-4  \quad Kf
HL ⇄ H+ +L-  \quad Ka
What is the equilibrium constant, Koverall, for the reaction, M m++ 4 HL ⇄ [ML4 ]m + 4 +4H+?

Accepted Answer

A)  KfKa
B)  Kf+ 4Ka
C)  Kf + Ka4
D)  KfKa4
E)  KfKa1/4 F) B) and E)
G) A) and E)

Question 4

A chemist is planning to study a chemical equilibrium for which no measured explicit thermodynamic values are available.However, the reaction involves common chemical species.What information could a chemist use to make predictions about the equilibrium?

Accepted Answer

A)  equilibrium constants for the equilibrium reactions that can be combined to make the new equilibrium
B)  ( Δ\DeltaΔ G °\degree° f values for the reactants and products of the new reaction) 
C)  ( Δ\DeltaΔ Hf and S °\degree°  values for the reactants and products of the new reaction) 
D)  only b and c
E)  All of these are correct. F) B) and C)
G) A) and C)

Question 5

A student can accept that  Δ\DeltaΔ G= -RT ln K but cannot reconcile the relationship between  Δ\DeltaΔ S °\degree°  and ln K.Choose the equation that shows this relationship.

Accepted Answer

A)  ( Δ\DeltaΔ S °\degree°  = R ln K -  Δ\DeltaΔ H °\degree° /T) 
B)  ( Δ\DeltaΔ S °\degree°  = +ln(K/R)  + Δ\DeltaΔ H °\degree° /T) 
C)  ( Δ\DeltaΔ S °\degree° = +R ln(K/T)  +  Δ\DeltaΔ H °\degree° ) 
D)  ( Δ\DeltaΔ S °\degree°  =+R ln K + Δ\DeltaΔ H °\degree° /T) 
E)  ( Δ\DeltaΔ S °\degree° = -R ln K+ Δ\DeltaΔ H °\degree° /T)  F) C) and E)
G) B) and E)

Question 6

For a chemical reaction at equilibrium, which action(s)  below will change the value of the equilibrium constant K? I.Changing the temperature
II) Changing the total concentration of reactants and products
III) Changing the reaction coefficients

Accepted Answer

A)  I only
B)  II only
C)  III only
D)  I and II only
E)  I and III onlyF) B) and C)
G) D) and E)

Question 7

What happens to the equilibrium between NO2(g)  and N2O4(g)  in inert argon when the volume is increased and additional argon is added to maintain a constant total pressure?

Accepted Answer

A)  The ratio of NO2 to N2O4 increases solely because of the increase in volume.
B)  The ratio of NO2 to N2O4 increases solely because of the addition of argon.
C)  The ratio of NO2 to N2O4 decreases solely because of the increase in volume.
D)  The ratio of NO2 to N2O4 decreases solely because of the addition of argon.
E)  The ratio of NO2 to N2O4 remains the same, as the effects of the two processes cancel.F) A) and B)
G) A) and C)

Question 8

For the reaction 2 H2 S(g)  ⇆ 2 H2 (g)  + S2 (g) , Kp =1.5 * 10-5 at 800.0 °\degree° 
C.If the initial partial pressures of H2 and S2 in a closed container are 4.00 atm and 2.00 atm, respectively, what is the approximate equilibrium partial pressure of H2S?

Accepted Answer

A)  0.0783 atm
B)  0.0493 atm
C)  0.0247 atm
D)  3.95 atm
E)  3.92 atm F) C) and D)
G) None of the above

Question 9

Calculate $\Delta$H$\degree$ for the reaction $ \mathrm{PCl}_{5}(g) \leftrightarrows \mathrm{PCl}_{3}(g)+\mathrm{Cl}_{2}(g) $ given the following data:

Accepted Answer

The answer of Calculate $\Delta$H$\degree$ for the reaction \( \mathrm{PCl}_{5}(g)...

Question 10

For the equilibrium 2 NOBr(g)  ⇄ 2 NO(g)  + Br2 (g) , Kc = 1.56 * 10-3 at 300 K.Suppose 0.400 M NOBr is placed in a reaction vessel at 300 K.At a given point, the concentration of Br2 is 0.0134 M.Which statement below is true?

Accepted Answer

A) Q <\lt< K, so the reaction will continue to make more products. B) Q >\gt> K, so the reaction will consume products to make more reactants. C) Q = K, so the system is at equilibrium. D) The value of K will decrease until it is equal to Q. E) The value of K will increase until it is equal to Q. F) D) and E) G) A) and B)

Question 11

Consider the following equilibrium: CO(g)  +3 H2 (g)  ⇄ CH4 (g)  +H2O(g) .If Kp = 1.61 *10-5 at 1400.0 K, calculate Kc.

Accepted Answer

A)  1.40 * 10-7
B)  1.85 * 10-3
C)  541
D)  0.212
E)  1.22 * 10-9F) C) and D)
G) B) and D)

Question 12

An equilibrium that strongly favors products has

Accepted Answer

A)  a value of K  ≪\ll≪  1.
B)  a value of K   ≫\gg≫  1.
C)  a value of Q  ≫\gg≫ 1.
D)  a value of Q   ≪\ll≪   1.
E)  K = Q. F) All of the above
G) A) and D)

Question 13

If the reaction quotient Q has a smaller value than the related equilibrium constant K,

Accepted Answer

A)  the reaction is at equilibrium.
B)  the reaction will continue to make more products.
C)  the reaction will consume products and make reactants.
D)  the reaction will release heat to achieve equilibrium.
E)  the value of K will decrease until it is equal to Q.F) A) and E)
G) B) and C)

Question 14

Which of the following is/are equal once equilibrium is established?

Accepted Answer

A)  the concentrations of reactant and products
B)  the rates of the forward and reverse reactions
C)  the time that a particular atom or molecule spends as a reactant and product
D)  the rate constants of the forward and reverse reactions
E)  All of the above are equal.F) C) and D)
G) B) and E)

Question 15

When can an x be ignored in solving an equilibrium expression derived from a RICE table?

Accepted Answer

A)  whenever it simplifies the calculation
B)  whenever it is very much smaller than the term it is added to or subtracted from
C)  whenever the equilibrium concentration for that species is relatively very small
D)  whenever it is raised to any power higher than 1
E)  neverF) A) and C)
G) B) and D)

Question 16

If the reaction quotient Q has a larger value than the related equilibrium constant K,

Accepted Answer

A)  the reaction is at equilibrium.
B)  the reaction will continue to make more products.
C)  the reaction will consume products and make reactants.
D)  the reaction will release heat to achieve equilibrium.
E)  the value of K will increase until it is equal to Q.F) All of the above
G) C) and D)

Question 17

Cylinders of NO gas may contain small quantities of oxygen as impurities, leading to the formation of NO2 in equilibrium with the NO and oxygen.Is this contamination by NO2 dependent on pressure in the tank?

Accepted Answer

A)  Yes, there will be more NO2 at higher pressures.
B)  Yes, there will be less NO2 at higher pressures.
C)  No, the amount of NO2 has nothing to do with pressure.
D)  No, the amount of NO2 depends on the partial pressure, not the total pressure.
E)  There is no way to tell without additional information.F) A) and E)
G) A) and B)

Question 18

In the atmosphere, nitrogen gas can react with ozone (O3) to form nitrogen dioxide and oxygen gas.Write the balanced reaction equilibrium using the smallest whole-number coefficients possible.Determine the equilibrium constant for this reaction under standard conditions from the following data and note whether the reaction is product favored or reactant favored.
$ \Delta G^{\circ}\left(\mathrm{O}_{3}, g\right)=163.2 \mathrm{~kJ} / \mathrm{mol} $
$ \Delta G^{\circ}\left(\mathrm{NO}_{2}, g\right)=51.3 \mathrm{~kJ} / \mathrm{mol} $

Accepted Answer

; the reac...

Question 19

Iodic acid, HIO3, dissociates in water according to the following reaction.
$ \mathrm{HIO}_{3}(a q) \leftrightarrows \mathrm{H}^{+}(a q)+\mathrm{IO}_{3}^{-}(a q) \quad K_{\mathrm{c}}=0.17 $ What is the concentration of H+ in a 0.0100 M solution of HIO3?

Accepted Answer

Use the quadratic fo...

Question 20

Consider the equilibrium 2 NOCl(g)  ⇄ CL2 (g)  + 2 NO(g) .When 2.000 atm NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium partial pressure of Cl2 is 0.226 atm.Calculate Kp.

Accepted Answer

A)  0.0115
B)  15.2
C)  0.0193
D)  0.0660
E)  52.0F) B) and E)
G) C) and D)

Exam 14: Chemical Equilibrium Equal but Opposite Reaction Rates

Correct Answer
verified

For a chemical reaction at equilibrium, which action(s) below will change the value of the equilibrium constant K? I.Changing the temperature II) Changing the total concentration of reactants and products III) Changing the reaction coefficients

Correct Answer
verified

Calculate $\Delta$ H $\degree$ for the reaction $\mathrm{PCl}_{5}(g) \leftrightarrows \mathrm{PCl}_{3}(g)+\mathrm{Cl}_{2}(g)$ given the following data: $Calculate \Delta H \degree for the reaction \mathrm{PCl}_{5}(g) \leftrightarrows \mathrm{PCl}_{3}(g)+\mathrm{Cl}_{2}(g) given the following data:$

Correct Answer
verified

When can an x be ignored in solving an equilibrium expression derived from a RICE table?

Correct Answer
verified

Iodic acid, HIO₃, dissociates in water according to the following reaction. $\mathrm{HIO}_{3}(a q) \leftrightarrows \mathrm{H}^{+}(a q)+\mathrm{IO}_{3}^{-}(a q) \quad K_{\mathrm{c}}=0.17$ What is the concentration of H⁺ in a 0.0100 M solution of HIO₃?

Correct Answer
verified
Use the quadratic fo...
View Answer

An equilibrium that strongly favors products has

Correct Answer
verified

Consider the equilibrium 2 NOCl(g) ⇄ CL₂ (g) + 2 NO(g) .When 2.000 atm NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium partial pressure of Cl₂ is 0.226 atm.Calculate K_p.

Correct Answer
verified

For the reaction 2 H₂ S(g) ⇆ 2 H₂ (g) + S₂ (g) , K_p =1.5 * 10^-5 at 800.0 $\degree$ C.If the initial partial pressures of H₂ and S₂ in a closed container are 4.00 atm and 2.00 atm, respectively, what is the approximate equilibrium partial pressure of H₂S?

Correct Answer
verified

Correct Answer
verified
; the reac...
View Answer

What happens to the equilibrium between NO₂(g) and N₂O₄(g) in inert argon when the volume is increased and additional argon is added to maintain a constant total pressure?

Correct Answer
verified

If the reaction quotient Q has a smaller value than the related equilibrium constant K,

Correct Answer
verified

For the equilibrium 2 NOBr(g) ⇄ 2 NO(g) + Br₂ (g) , K_c = 1.56 * 10^-3 at 300 K.Suppose 0.400 M NOBr is placed in a reaction vessel at 300 K.At a given point, the concentration of Br₂ is 0.0134 M.Which statement below is true?

Correct Answer
verified

Which of the following is/are equal once equilibrium is established?

Correct Answer
verified

Which statement below concerning a chemical reaction at equilibrium is true?

Correct Answer
verified

If the reaction quotient Q has a larger value than the related equilibrium constant K,

Correct Answer
verified

A chemist is planning to study a chemical equilibrium for which no measured explicit thermodynamic values are available.However, the reaction involves common chemical species.What information could a chemist use to make predictions about the equilibrium?

Correct Answer
verified

Cylinders of NO gas may contain small quantities of oxygen as impurities, leading to the formation of NO₂ in equilibrium with the NO and oxygen.Is this contamination by NO₂ dependent on pressure in the tank?

Correct Answer
verified

The equilibrium constants for the two reactions are known: M ^m++ 4 L^- ⇄ [ML4]^m^-⁴ $\quad$ K_f HL ⇄ H⁺ +L^- $\quad$ K_a What is the equilibrium constant, K_overall, for the reaction, M ^m++ 4 HL ⇄ [ML4 ]^m ⁺ ⁴ +4H⁺?

Correct Answer
verified

A student can accept that $\Delta$ G= -RT ln K but cannot reconcile the relationship between $\Delta$ S $\degree$ and ln K.Choose the equation that shows this relationship.

Correct Answer
verified

Consider the following equilibrium: CO(g) +3 H₂ (g) ⇄ CH₄ (g) +H₂O(g) .If K_p = 1.61 *10^-5 at 1400.0 K, calculate K_c.

Correct Answer
verified

Exam 14: Chemical Equilibrium Equal but Opposite Reaction Rates

For the phase transition H2O2 (l) ⇄ H2O2 (g) at 298 K, Δ\DeltaΔ G °\degree° = 14.8 kJ/mol.Calculate Δ\DeltaΔ G when the partial pressure of hydrogen peroxide in a closed container is 1.00 torr.Will liquid H 2O2 spontaneously evaporate, or will vapor phase H2O2 spontaneously condense?

Correct AnswerverifiedShow Answer

For a chemical reaction at equilibrium, which action(s) below will change the value of the equilibrium constant K? I.Changing the temperature II) Changing the total concentration of reactants and products III) Changing the reaction coefficients

Correct AnswerverifiedShow Answer

Calculate Δ\DeltaΔ H °\degree° for the reaction PCl5(g)⇆PCl3(g)+Cl2(g) \mathrm{PCl}_{5}(g) \leftrightarrows \mathrm{PCl}_{3}(g)+\mathrm{Cl}_{2}(g) PCl5​(g)⇆PCl3​(g)+Cl2​(g) given the following data:

Correct AnswerverifiedShow Answer

When can an x be ignored in solving an equilibrium expression derived from a RICE table?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedUse the quadratic fo...View AnswerShow Answer

An equilibrium that strongly favors products has

Correct AnswerverifiedShow Answer

Consider the equilibrium 2 NOCl(g) ⇄ CL2 (g) + 2 NO(g) .When 2.000 atm NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium partial pressure of Cl2 is 0.226 atm.Calculate Kp.

Correct AnswerverifiedShow Answer

For the reaction 2 H2 S(g) ⇆ 2 H2 (g) + S2 (g) , Kp =1.5 * 10-5 at 800.0 °\degree° C.If the initial partial pressures of H2 and S2 in a closed container are 4.00 atm and 2.00 atm, respectively, what is the approximate equilibrium partial pressure of H2S?

Correct AnswerverifiedShow Answer

Correct Answerverified; the reac...View AnswerShow Answer

What happens to the equilibrium between NO2(g) and N2O4(g) in inert argon when the volume is increased and additional argon is added to maintain a constant total pressure?

Correct AnswerverifiedShow Answer

If the reaction quotient Q has a smaller value than the related equilibrium constant K,

Correct AnswerverifiedShow Answer

For the equilibrium 2 NOBr(g) ⇄ 2 NO(g) + Br2 (g) , Kc = 1.56 * 10-3 at 300 K.Suppose 0.400 M NOBr is placed in a reaction vessel at 300 K.At a given point, the concentration of Br2 is 0.0134 M.Which statement below is true?

Correct AnswerverifiedShow Answer

Which of the following is/are equal once equilibrium is established?

Correct AnswerverifiedShow Answer

Which statement below concerning a chemical reaction at equilibrium is true?

Correct AnswerverifiedShow Answer

If the reaction quotient Q has a larger value than the related equilibrium constant K,

Correct AnswerverifiedShow Answer

A chemist is planning to study a chemical equilibrium for which no measured explicit thermodynamic values are available.However, the reaction involves common chemical species.What information could a chemist use to make predictions about the equilibrium?

Correct AnswerverifiedShow Answer

Cylinders of NO gas may contain small quantities of oxygen as impurities, leading to the formation of NO2 in equilibrium with the NO and oxygen.Is this contamination by NO2 dependent on pressure in the tank?

Correct AnswerverifiedShow Answer

The equilibrium constants for the two reactions are known: M m++ 4 L- ⇄ [ML4]m-4 \quad Kf HL ⇄ H+ +L- \quad Ka What is the equilibrium constant, Koverall, for the reaction, M m++ 4 HL ⇄ [ML4 ]m + 4 +4H+?

Correct AnswerverifiedShow Answer

A student can accept that Δ\DeltaΔ G= -RT ln K but cannot reconcile the relationship between Δ\DeltaΔ S °\degree° and ln K.Choose the equation that shows this relationship.

Correct AnswerverifiedShow Answer

Consider the following equilibrium: CO(g) +3 H2 (g) ⇄ CH4 (g) +H2O(g) .If Kp = 1.61 *10-5 at 1400.0 K, calculate Kc.

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Calculate $\Delta$ H $\degree$ for the reaction $\mathrm{PCl}_{5}(g) \leftrightarrows \mathrm{PCl}_{3}(g)+\mathrm{Cl}_{2}(g)$ given the following data: $Calculate \Delta H \degree for the reaction \mathrm{PCl}_{5}(g) \leftrightarrows \mathrm{PCl}_{3}(g)+\mathrm{Cl}_{2}(g) given the following data:$

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Use the quadratic fo...
View Answer

Correct Answer
verified

Consider the equilibrium 2 NOCl(g) ⇄ CL₂ (g) + 2 NO(g) .When 2.000 atm NOCl is placed in an empty tank at 500.0 K and allowed to come to equilibrium, the equilibrium partial pressure of Cl₂ is 0.226 atm.Calculate K_p.

Correct Answer
verified

For the reaction 2 H₂ S(g) ⇆ 2 H₂ (g) + S₂ (g) , K_p =1.5 * 10^-5 at 800.0 $\degree$ C.If the initial partial pressures of H₂ and S₂ in a closed container are 4.00 atm and 2.00 atm, respectively, what is the approximate equilibrium partial pressure of H₂S?

Correct Answer
verified

Correct Answer
verified
; the reac...
View Answer

What happens to the equilibrium between NO₂(g) and N₂O₄(g) in inert argon when the volume is increased and additional argon is added to maintain a constant total pressure?

Correct Answer
verified

Correct Answer
verified

For the equilibrium 2 NOBr(g) ⇄ 2 NO(g) + Br₂ (g) , K_c = 1.56 * 10^-3 at 300 K.Suppose 0.400 M NOBr is placed in a reaction vessel at 300 K.At a given point, the concentration of Br₂ is 0.0134 M.Which statement below is true?

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Cylinders of NO gas may contain small quantities of oxygen as impurities, leading to the formation of NO₂ in equilibrium with the NO and oxygen.Is this contamination by NO₂ dependent on pressure in the tank?

Correct Answer
verified

The equilibrium constants for the two reactions are known: M ^m++ 4 L^- ⇄ [ML4]^m^-⁴ $\quad$ K_f HL ⇄ H⁺ +L^- $\quad$ K_a What is the equilibrium constant, K_overall, for the reaction, M ^m++ 4 HL ⇄ [ML4 ]^m ⁺ ⁴ +4H⁺?

Correct Answer
verified

A student can accept that $\Delta$ G= -RT ln K but cannot reconcile the relationship between $\Delta$ S $\degree$ and ln K.Choose the equation that shows this relationship.

Correct Answer
verified

Consider the following equilibrium: CO(g) +3 H₂ (g) ⇄ CH₄ (g) +H₂O(g) .If K_p = 1.61 *10^-5 at 1400.0 K, calculate K_c.

Correct Answer
verified