Question 1

Consider the following reaction at equilibrium. What effect will adding KCl have on the system? 2KClO3(s) ⇌ 2KCl(s) + 3O2(g)

Accepted Answer

A)  No effect will be observed since KCl is a solid and is not included in the equilibrium expression. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will increase. 
E)  The reaction will shift in the direction of products. 
A)  No effect will be observed since KCl is a solid and is not included in the equilibrium expression. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will increase. 
E)  The reaction will shift in the direction of products.

Question 2

Consider the following reaction and its equilibrium constant: SO2(g) + NO2(g) ⇌ SO3(g) + NO(g) Kc = 0.33
A reaction mixture contains 1.0 mol L-1 SO2, 0.50 mol L-1 NO2 , 0.50 mol L-1 SO3, and 1.0 mol L-1 NO. Which of the following statements is TRUE concerning this system?

Accepted Answer

A)  The reaction will shift in the direction of reactants. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of products. 
D)  The reaction quotient will decrease. 
E)  The system is at equilibrium. 
A)  The reaction will shift in the direction of reactants. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of products. 
D)  The reaction quotient will decrease. 
E)  The system is at equilibrium.

Question 3

The reaction below has a Kp value of 41 bar-2. What is the value of Kc for this reaction at 400 K? N2(g) + 3H2(g) ⇌ 2NH3(g)

Accepted Answer

A)  2.4 × 10-2 M-2 
B)  4.4 × 104 M-2 
C)  41 M-2 
D)  2.3 × 10-5 M-2 
E)  1.9 × 104 M-2 
A)  2.4 × 10-2 M-2 
B)  4.4 × 104 M-2 
C)  41 M-2 
D)  2.3 × 10-5 M-2 
E)  1.9 × 104 M-2

Question 4

Which of the following statements is TRUE about the implication of K ≈ 1?

Accepted Answer

A)  At equilibrium, the amount of products is favoured over the amount of reactants. 
B)  At equilibrium, the amount of reactants is favoured over the amount of products. 
C)  The rate of the reaction is fast. 
D)  The reverse reaction is favoured. 
E)  Neither the forward nor reverse reaction is strongly favoured; the forward reaction proceeds about halfway. 
A)  At equilibrium, the amount of products is favoured over the amount of reactants. 
B)  At equilibrium, the amount of reactants is favoured over the amount of products. 
C)  The rate of the reaction is fast. 
D)  The reverse reaction is favoured. 
E)  Neither the forward nor reverse reaction is strongly favoured; the forward reaction proceeds about halfway.

Question 5

For the following reaction, what is Δn required in the conversion of Kc to Kp? N2O4(g) ⇌ 2NO2(g)

Accepted Answer

A)  3 
B)  -1 
C)  -2 
D)  2 
E)  1 
A)  3 
B)  -1 
C)  -2 
D)  2 
E)  1

Question 6

Consider the following reaction and its equilibrium constant: SO2(g) + NO2(g) ⇌ SO3(g) + NO(g) Kc = 0.33
A reaction mixture contains 0.39 mol L-1 SO2, 0.14 mol L-1 NO2 , 0.11 mol L-1 SO3 and 0.14 mol L-1 NO. Which of the following statements is TRUE concerning this system?

Accepted Answer

A)  The reaction will shift in the direction of reactants. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of products. 
D)  The reaction quotient will decrease. 
E)  The system is at equilibrium. 
A)  The reaction will shift in the direction of reactants. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of products. 
D)  The reaction quotient will decrease. 
E)  The system is at equilibrium.

Question 7

Consider the following reaction and its equilibrium constant: I2(g) + Br2(g) ⇌ 2IBr(g) Kc = 1.1 × 102
A reaction mixture contains 0.41 mol L-1 I2, 0.27 mol L-1 Br2 and 3.5 mol L-1 IBr. Which of the following statements is TRUE concerning this system?

Accepted Answer

A)  The reaction will shift in the direction of products. 
B)  The reaction will shift in the direction of reactants. 
C)  The reaction quotient will decrease. 
D)  The equilibrium constant will increase. 
E)  The system is at equilibrium. 
A)  The reaction will shift in the direction of products. 
B)  The reaction will shift in the direction of reactants. 
C)  The reaction quotient will decrease. 
D)  The equilibrium constant will increase. 
E)  The system is at equilibrium.

Question 8

Express the equilibrium constant for the following reaction: PCl5(g) ⇌ PCl3(g) + Cl2(g)

Accepted Answer

A)  KP =   
B)  KP =   
C)  KP =   
D)  KP =   
E)  KP =   
A)  KP =   
B)  KP =   
C)  KP =   
D)  KP =   
E)  KP =

Question 9

Consider the following reaction at equilibrium. What effect will adding a catalyst have on the system? 2KClO3(s) ⇌ 2KCl(s) + 3O2(g)

Accepted Answer

A)  There will be no change in the equilibrium constant. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will increase. 
E)  The reaction will shift in the direction of products. 
A)  There will be no change in the equilibrium constant. 
B)  The equilibrium constant will decrease. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will increase. 
E)  The reaction will shift in the direction of products.

Question 10

Consider the following reaction at equilibrium. What effect will adding 1 mole of Ar to the reaction mixture have on the system? 2H2S(g) + 3O2(g) ⇌ 2H2O(g) + 2SO2(g)

Accepted Answer

A)  The reaction will shift in the direction of products. 
B)  No effect will be observed. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will decrease. 
E)  The equilibrium constant will increase. 
A)  The reaction will shift in the direction of products. 
B)  No effect will be observed. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will decrease. 
E)  The equilibrium constant will increase.

Question 11

For the reaction: N2(g) + 2O2(g) ⇌ 2NO2(g), Kc = 8.3 × 10-10 M-1 at 25 °C. What is the concentration of N2 gas at equilibrium when the concentration of NO2 is five times the concentration of O2 gas?

Accepted Answer

A)  3.3 × 10-11 mol L-1 
B)  1.7 × 10-10 mol L-1 
C)  6.0 × 109 mol L-1 
D)  3.0 × 1010 mol L-1 
A)  3.3 × 10-11 mol L-1 
B)  1.7 × 10-10 mol L-1 
C)  6.0 × 109 mol L-1 
D)  3.0 × 1010 mol L-1

Question 12

Consider the following reaction, equilibrium pressures, and equilibrium constant at a particular temperature. Determine the equilibrium pressure of H2. D2(g) + H2(g) ⇌ 2HD(g) Kp = 1.80
P(D2)eq = 1.1 × 10-3 bar P(HD)eq = 2.7 × 10-3 bar

Accepted Answer

A)  2.7 bar 
B)  1.4 bar 
C)  0.73 bar 
D)  3.7 × 10-3 bar 
E)  8.1 × 10-4 bar 
A)  2.7 bar 
B)  1.4 bar 
C)  0.73 bar 
D)  3.7 × 10-3 bar 
E)  8.1 × 10-4 bar

Question 13

Cyclohexane (C6H12) undergoes a molecular rearrangement in the presence of AlCl3 to form methylcyclopentane (MCP) according to the equation: C6H12 ⇌ MCP
If Kc = 0.143 at 25 °C for this reaction, predict the direction in which the system will shift if the initial concentrations of C6H12 and MCP are 0. 0400 mol L-1 and 0. 0200 mol L-1, respectively. The system ________.

Accepted Answer

A)  will shift left 
B)  will shift right 
C)  is already at equilibrium 
D)  is not at equilibrium and will remain in an unequilibrated state 
A)  will shift left 
B)  will shift right 
C)  is already at equilibrium 
D)  is not at equilibrium and will remain in an unequilibrated state

Question 14

Consider the following reaction: CuS(s) + O2(g) ⇌ Cu(s) + SO2(g)
A reaction mixture initially contains 2.9 mol L-1 O2. Determine the equilibrium concentration of O2 if Kc for the reaction at this temperature is 1.5.

Accepted Answer

A)  1.9 mol L-1 
B)  1.7 mol L-1 
C)  2.2 mol L-1 
D)  1.2 mol L-1 
E)  0.59 mol L-1 
A)  1.9 mol L-1 
B)  1.7 mol L-1 
C)  2.2 mol L-1 
D)  1.2 mol L-1 
E)  0.59 mol L-1

Question 15

Consider the following reaction: NO(g) + SO3(g) ⇌ NO2(g) + SO2(g)
A reaction mixture initially contains 0.86 bar NO and 0.86 bar SO3. Determine the equilibrium pressure of NO2 if Kp for the reaction at this temperature is 0.0118.

Accepted Answer

A)  0.78 bar 
B)  0.084 bar 
C)  0.012 bar 
D)  0.85 bar 
E)  0.048 bar 
A)  0.78 bar 
B)  0.084 bar 
C)  0.012 bar 
D)  0.85 bar 
E)  0.048 bar

Question 16

The equilibrium constant is given for two of the reactions below. Determine the value of the missing equilibrium constant. A(g) + B(g) ⇌ AB(g) K = 0.24
AB(g) + A(g) ⇌ A2B(g) K = 3.8
2A(g) + B(g) ⇌ A2B(g) K = ?

Accepted Answer

A)  4.0 
B)  0.91 
C)  3.6 
D)  16 
E)  0.63 
A)  4.0 
B)  0.91 
C)  3.6 
D)  16 
E)  0.63

Question 17

The reaction below has a Kp value of 3.3 × 10-5 bar. What is the value of Kc for this reaction at 700 K? 2SO3(g) ⇌ 2SO2(g) + O2(g)

Accepted Answer

A)  5.7 × 10-7 M 
B)  1.7 × 106 M 
C)  3.3 × 10-5 M 
D)  3.0 × 104 M 
E)  1.9 × 10-3 M 
A)  5.7 × 10-7 M 
B)  1.7 × 106 M 
C)  3.3 × 10-5 M 
D)  3.0 × 104 M 
E)  1.9 × 10-3 M

Question 18

The following reaction is exothermic. Which change will shift the equilibrium to the right? C2H4(g) + Cl2(g) ⇌ C2H4Cl2(g)

Accepted Answer

A)  raising the temperature 
B)  increasing the pressure 
C)  increasing the volume 
D)  adding a catalyst 
A)  raising the temperature 
B)  increasing the pressure 
C)  increasing the volume 
D)  adding a catalyst

Question 19

Explain dynamic equilibrium. Use the generic reaction A(g) ⇌ B(g) to explain.

Accepted Answer

In this reaction, dynamic equilibrium me

Question 20

Consider the following reaction at equilibrium. What effect will increasing the volume of the reaction mixture have on the system? 2H2S(g) + 3O2(g) ⇌ 2H2O(g) + 2SO2(g)

Accepted Answer

A)  The reaction will shift in the direction of products. 
B)  No effect will be observed. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will decrease. 
E)  The equilibrium constant will increase. 
A)  The reaction will shift in the direction of products. 
B)  No effect will be observed. 
C)  The reaction will shift in the direction of reactants. 
D)  The equilibrium constant will decrease. 
E)  The equilibrium constant will increase.

Exam 14: Chemical Equilibrium

Consider the following reaction at equilibrium. What effect will adding KCl have on the system? 2KClO3(s) ⇌ 2KCl(s) + 3O2(g)

Consider the following reaction and its equilibrium constant: SO2(g) + NO2(g) ⇌ SO3(g) + NO(g) Kc = 0.33 A reaction mixture contains 1.0 mol L-1 SO2, 0.50 mol L-1 NO2 , 0.50 mol L-1 SO3, and 1.0 mol L-1 NO. Which of the following statements is TRUE concerning this system?

The reaction below has a Kp value of 41 bar-2. What is the value of Kc for this reaction at 400 K? N2(g) + 3H2(g) ⇌ 2NH3(g)

Which of the following statements is TRUE about the implication of K ≈ 1?

For the following reaction, what is Δn required in the conversion of Kc to Kp? N2O4(g) ⇌ 2NO2(g)

Consider the following reaction and its equilibrium constant: SO2(g) + NO2(g) ⇌ SO3(g) + NO(g) Kc = 0.33 A reaction mixture contains 0.39 mol L-1 SO2, 0.14 mol L-1 NO2 , 0.11 mol L-1 SO3 and 0.14 mol L-1 NO. Which of the following statements is TRUE concerning this system?

Consider the following reaction and its equilibrium constant: I2(g) + Br2(g) ⇌ 2IBr(g) Kc = 1.1 × 102 A reaction mixture contains 0.41 mol L-1 I2, 0.27 mol L-1 Br2 and 3.5 mol L-1 IBr. Which of the following statements is TRUE concerning this system?

Express the equilibrium constant for the following reaction: PCl5(g) ⇌ PCl3(g) + Cl2(g)

Consider the following reaction at equilibrium. What effect will adding a catalyst have on the system? 2KClO3(s) ⇌ 2KCl(s) + 3O2(g)

Consider the following reaction at equilibrium. What effect will adding 1 mole of Ar to the reaction mixture have on the system? 2H2S(g) + 3O2(g) ⇌ 2H2O(g) + 2SO2(g)

For the reaction: N2(g) + 2O2(g) ⇌ 2NO2(g), Kc = 8.3 × 10-10 M-1 at 25 °C. What is the concentration of N2 gas at equilibrium when the concentration of NO2 is five times the concentration of O2 gas?

Consider the following reaction, equilibrium pressures, and equilibrium constant at a particular temperature. Determine the equilibrium pressure of H2. D2(g) + H2(g) ⇌ 2HD(g) Kp = 1.80 P(D2)eq = 1.1 × 10-3 bar P(HD)eq = 2.7 × 10-3 bar

Consider the following reaction: CuS(s) + O2(g) ⇌ Cu(s) + SO2(g) A reaction mixture initially contains 2.9 mol L-1 O2. Determine the equilibrium concentration of O2 if Kc for the reaction at this temperature is 1.5.

Consider the following reaction: NO(g) + SO3(g) ⇌ NO2(g) + SO2(g) A reaction mixture initially contains 0.86 bar NO and 0.86 bar SO3. Determine the equilibrium pressure of NO2 if Kp for the reaction at this temperature is 0.0118.

The equilibrium constant is given for two of the reactions below. Determine the value of the missing equilibrium constant. A(g) + B(g) ⇌ AB(g) K = 0.24 AB(g) + A(g) ⇌ A2B(g) K = 3.8 2A(g) + B(g) ⇌ A2B(g) K = ?

The reaction below has a Kp value of 3.3 × 10-5 bar. What is the value of Kc for this reaction at 700 K? 2SO3(g) ⇌ 2SO2(g) + O2(g)

The following reaction is exothermic. Which change will shift the equilibrium to the right? C2H4(g) + Cl2(g) ⇌ C2H4Cl2(g)

Explain dynamic equilibrium. Use the generic reaction A(g) ⇌ B(g) to explain.

Consider the following reaction at equilibrium. What effect will increasing the volume of the reaction mixture have on the system? 2H2S(g) + 3O2(g) ⇌ 2H2O(g) + 2SO2(g)

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Filters

Consider the following reaction at equilibrium. What effect will adding KCl have on the system? 2KClO₃(s) ⇌ 2KCl(s) + 3O₂(g)

Consider the following reaction and its equilibrium constant: SO₂(g) + NO₂(g) ⇌ SO₃(g) + NO(g) K_c = 0.33 A reaction mixture contains 1.0 mol L^-1 SO₂, 0.50 mol L^-1 NO₂, 0.50 mol L^-1 SO₃, and 1.0 mol L^-1 NO. Which of the following statements is TRUE concerning this system?

The reaction below has a K_p value of 41 bar^-2. What is the value of K_c for this reaction at 400 K? N₂(g) + 3H₂(g) ⇌ 2NH₃(g)

For the following reaction, what is Δn required in the conversion of K_c to K_p? N₂O₄(g) ⇌ 2NO₂(g)

Consider the following reaction and its equilibrium constant: SO₂(g) + NO₂(g) ⇌ SO₃(g) + NO(g) K_c = 0.33 A reaction mixture contains 0.39 mol L^-1 SO₂, 0.14 mol L^-1 NO₂, 0.11 mol L^-1 SO₃ and 0.14 mol L^-1 NO. Which of the following statements is TRUE concerning this system?

Consider the following reaction and its equilibrium constant: I₂(g) + Br₂(g) ⇌ 2IBr(g) K_c = 1.1 × 10² A reaction mixture contains 0.41 mol L^-1 I₂, 0.27 mol L^-1 Br₂and 3.5 mol L^-1 IBr. Which of the following statements is TRUE concerning this system?

Express the equilibrium constant for the following reaction: PCl₅(g) ⇌ PCl₃(g) + Cl₂(g)

Consider the following reaction at equilibrium. What effect will adding a catalyst have on the system? 2KClO₃(s) ⇌ 2KCl(s) + 3O₂(g)

Consider the following reaction at equilibrium. What effect will adding 1 mole of Ar to the reaction mixture have on the system? 2H₂S(g) + 3O₂(g) ⇌ 2H₂O(g) + 2SO₂(g)

For the reaction: N₂(g) + 2O₂(g) ⇌ 2NO₂(g), K_c = 8.3 × 10^-10 M^-1at 25 °C. What is the concentration of N₂ gas at equilibrium when the concentration of NO₂ is five times the concentration of O₂ gas?

Consider the following reaction, equilibrium pressures, and equilibrium constant at a particular temperature. Determine the equilibrium pressure of H₂. D₂(g) + H₂(g) ⇌ 2HD(g) K_p = 1.80 P(D₂)_eq = 1.1 × 10^-3bar P(HD)_eq = 2.7 × 10^-3 bar

Consider the following reaction: CuS(s) + O₂(g) ⇌ Cu(s) + SO₂(g) A reaction mixture initially contains 2.9 mol L^-1 O₂. Determine the equilibrium concentration of O₂ if K_c for the reaction at this temperature is 1.5.

Consider the following reaction: NO(g) + SO₃(g) ⇌ NO₂(g) + SO₂(g) A reaction mixture initially contains 0.86 bar NO and 0.86 bar SO₃. Determine the equilibrium pressure of NO₂ if K_p for the reaction at this temperature is 0.0118.

The equilibrium constant is given for two of the reactions below. Determine the value of the missing equilibrium constant. A(g) + B(g) ⇌ AB(g) K = 0.24 AB(g) + A(g) ⇌ A₂B(g) K = 3.8 2A(g) + B(g) ⇌ A₂B(g) K = ?

The reaction below has a K_p value of 3.3 × 10^-5bar. What is the value of K_c for this reaction at 700 K? 2SO₃(g) ⇌ 2SO₂(g) + O₂(g)

The following reaction is exothermic. Which change will shift the equilibrium to the right? C₂H₄(g) + Cl₂(g) ⇌ C₂H₄Cl₂(g)

Consider the following reaction at equilibrium. What effect will increasing the volume of the reaction mixture have on the system? 2H₂S(g) + 3O₂(g) ⇌ 2H₂O(g) + 2SO₂(g)