Deck 10: An Introduction to Kinetics and Equilibrium

Question 1

The following reaction was carried out:
Ni(CO)₄ + PPh₃(g) $\rightarrow$ PPh₃Ni(CO)₃ + CO
Over 200 seconds, the concentration of Ni(CO)4 dropped from 10 M to 2.5 M. What is the average rate of the reaction in M/s over this time period?

A) -0.038 M/s
B) 0.050 M/s
C) -0.050 M/s
D) 1.5 x 10³ M/s
E) 0.038 M/s

Answer 1

0.038 M/s

Question 2

Describe the relationship between the rate constants k_f and k_r for the following one step reaction at equilibrium.

A) k_f = k_r
B) k_f < k_r
C) k_f > k_r
D) k_f = k_r = 0
E) none of these

Answer 2

k_f < k_r

Question 3

For the reaction:
CO(g) + Cl₂(g) COCl₂(g)
K_f is 1x 10⁷ M^-1-s^-1 and k_r = 2 x 10² s^-1.
What is the equilibrium constant for the reaction?

A) 2 x 10^-5
B) 5
C) 5 x 10⁴
D) 2 x 10⁹
E) none of these

Answer 3

5 x 10⁴

Question 4

-Which of the following reactions could be described by the above diagram?

A) 2 N₂O₂(g) 4 NO₂(g) + O₂(g)
B) H₂(g) + CO₂(g) CO(g) + H₂O(g)
C) PCl₅(g) PCl₃(g) + Cl₂(g)
D) 2 NO(g) + Br₂(g) 2 NOBr(g)
E) 2 O₃(g) 3 O₂(g)

Question 5

-What happens with respect to time to the products of this reaction in the kinetic region of the graph above?

A) the products increase
B) the products decrease
C) the products remain constant
D) cannot be determined from the graph

Question 6

-What happens to the rate of the reaction as time passes in the equilibrium region of the graph above?

A) the rate increases
B) the rate decreases
C) the rate remains constant
D) cannot be determined from the graph

Question 7

-From the graph above, which of the following is true when equilibrium has been reached?

A) The concentrations of the reactants are larger than the concentration of the products.
B) The concentrations of the products are larger than the concentration of the reactants.
C) The concentrations of the reactants and products are equal.
D) This cannot be determined from the graph.

Question 8

-Which of the following will be true concerning the K_c of the reaction described by the graph above?

A) K_c < 1
B) K_c > 1
C) K_c = 1
D) K_c cannot be determined from the graph

Question 9

For the following reaction:
2 NOCl(g) 2 NO₂(g) + Cl₂(g)   K_c = 5.6 x 10^-6 (at 400 K)
If (NOCl) = 0.0222 M, (Cl₂) = 0.0222 M, and (NO₂) = 0.989 M at some moment in time, which of the following would be true?

A) The rate of the forward reaction would be exactly equal to the rate of the reverse reaction.
B) Neither the forward nor the reverse reaction would occur because the reaction would be at equilibrium.
C) The rate of the forward reaction would be faster than the reverse reaction.
D) The rate of the reverse reaction would be faster than the forward reaction.
E) There is no relationship between these concentrations and the rate of either the forward or the reverse reaction.

Question 10

Which one of the following graphs best represents the relationship between the concentration of reactants and products with respect to time for the following chemical reaction?

2 NO₂(g) 2 NO(g) + O₂(g)

A)
B)
C)
D)
E)

Question 11

Use the following graph for answering


-Using the above graph determine the balanced chemical equation.

A) 3 A + B 2 C
B) 5 A + 3 B 2 C
C) 2 C + 3 B 5 A
D) A + B C
E) none of these

Question 12

Use the following graph for answering


-Which of the following will be true of the equilibrium constant, K_c, for the reaction described in the above graph?

A) K_c $\approx$ 1
B) K_c $\approx$ 0
C) K_c < 1
D) K_c > 1
E) cannot be determined from graph

Question 13

At equilibrium, ______________.

A) all chemical processes have ceased.
B) the rate of the forward reaction equals that of the reverse.
C) the rate constant for the forward reaction equals that of the reverse.
D) $\underline{\text{ both }}$ the rate of the forward reaction equals that of the reverse $\underline{\text{ and }}$ the rate constant for the forward reaction equals that of the reverse.
E) none of the above

Question 14

Which of the following graphs best represents the relationship between the concentration of reactants and products with respect to time for the following chemical reaction?

2 H₂(g) + O₂(g) 2 H₂O(g)

A)
B)
C)
D)
E)

Question 15

Assume that the equilibrium constants for the following reactions are known.

2 SO₂(g) + O₂(g) 2 SO₃(g)   K₁
2 CO(g) + O₂(g) 2 CO₂(g)   K₂
What is the equilibrium constant for the following reaction?
2 SO₂(g) + 2 CO₂(g) 2 SO₃(g) + 2 CO(g)

A) K = K₁ x K₂
B) K = K₁/K₂
C) K = K₂/K₁
D) K = K₁ + K₂
E) K = K₁ - K₂

Question 16

Which is the correct equilibrium constant expression for the reaction:

2 SO_2(g) + O_2(g) 2 SO_3(g)

A)
B)
C)
D)

Question 17

Assume that the equilibrium constant for the following reaction is known.

2 NO₂(g) 2 NO(g) + O₂(g)   K₁ = 7.4 x 10^-16 (at 25°C)

What is the correct value of the equilibrium constant for the opposite reaction?
2 NO(g) + O₂(g) 2 NO₂(g)   K₂ = ?

A) K₂ = K₁ = 7.4 x 10^-16
B) K₂ = 1/K₁ = 1.4 x 10¹⁵
C) K₂ = K₁(RT) = 1.8 x 10^-14
D) K₂ = K₁(RT)^-1 = 3.0 x 10^-17
E) impossible to determine from this information

Question 18

For the reaction shown below, at equilibrium
I₂(g) + Br₂(g) 2IBr(g)   K_c = 1.1 x 10²

A) Reactants and products will be present in approximately equal concentrations.
B) Reactants will be favored.
C) Products will be favored.
D) Insufficient information is given to decide.
E) It is impossible for the reaction to reach equilibrium.

Question 19

Based on the information given in the previous problem, the equilibrium constant for the following reaction would be:

2IBr(g) I₂(g) + Br₂(g)

A) -1.1 x 10²
B) 9.1 x 10^-3
C) 10.5
D) 1.1 x 10^-2
E) none of the above

Question 20

Under which set of conditions must the following reaction always proceed to the right in order to reach equilibrium?

H₂(g) + I₂(g) 2 HI(g)

A) Q_c < 1
B) Q_c > 1
C) Q_c = 1
D) Q_c > K_c
E) none of these

Question 21

Which of the following initial concentrations of reactants and products will cause the reaction to proceed to the right in order to establish equilibrium?
2 NO₂(g) 2 NO(g) + O₂(g) K_c=3.4*10 ^-F ⁷ (at 200 C)

A)
B)
C)
D)
E) none of these

Question 22

If at any moment in time, we find that Q_c is larger than K_c for the reaction
Cl₂(g) + 3 F₂(g) 2 ClF₃(g)
We can conclude that:

A) The reaction is at equilibrium.
B) The reaction cannot reach equilibrium.
C) The reaction must shift to the right to reach equilibrium.
D) The reaction must shift to the left to reach equilibrium.
E) None of the above are possible.

Question 23

Assume that the reaction quotient, Q_c, for the following reaction at 25°C is 1.0 x 10^-8
2 NO₂(g) 2 NO(g) + O₂(g)     K_c = 7.4 x 10^-16 (at 25°C)
From this we can conclude:

A) The reaction is at equilibrium.
B) Equilibrium could be reached by adding enough NO or O₂ to the system.
C) The reaction must proceed from left to right to reach equilibrium.
D) The reaction must proceed from right to left to reach equilibrium.
E) The reaction can never reach equilibrium.

Question 24

If the equilibrium constant for the following reaction is K_c = 1 x 10²
2 C₂H₆(g) + 7 O₂(g) 4 CO₂(g) + 6 H₂O(g)
And all the concentrations were initially 0.10 M, we can predict that the reaction

A) is at equilibrium initially.
B) must shift from left to right to reach equilibrium.
C) must shift from right to left to reach equilibrium.
D) cannot reach equilibrium.
E) cannot be determined unless we have the information necessary to calculate Q_c for the reaction.

Question 25

For the following reaction:
2 NOCl(g) 2 NO(g) + Cl₂(g)     K_c = 5.6 x 10^-6 (at 400 K)

If (NOCl) = 0.0222 M, (Cl₂) = 0.0222 M, and (NO) = 0.989
M at some moment in time, we can conclude that

A) the reaction is at equilibrium.
B) some of the NOCl must be converted to NO and Cl₂ to reach equilibrium.
C) some of the NO and Cl₂ must be converted to NOCl to reach equilibrium.
D) it is impossible to determine which way the reaction must go to reach equilibrium.
E) the reaction can never reach equilibrium.

Question 26

Suppose that the reaction quotient, Q_c, for a chemical reaction was found to be close to unity (Q_c $\approx$ 1). Given this information we can accurately predict

A) that the reaction will proceed in a direction to generate more product.
B) that the reaction will proceed in a direction to use up product.
C) that the reaction is close to equilibrium.
D) nothing about the direction in which the reaction will proceed without additional information.
E) none of the above.

Question 27

For the following reaction 2 NO₂(g) 2 NO(g) + O₂(g)   K_c = 7.4 x 10^-16 (at 25°C)
If (NO₂) = 0.10 M, (NO) = 0.010 M, and (O₂) = 1.0 x 10^-5 M, we can correctly predict

A) that the reaction is at equilibrium.
B) that the reaction must shift to the left to reach equilibrium.
C) that the reaction must shift to the right to reach equilibrium.
D) nothing related to the question as to whether the reaction is at equilibrium.
E) nothing related to the question as to which direction the reaction has to shift to reach equilibrium.

Question 28

The following reaction was carried out at 25⁰C with the initial concentration of NO₂ being 0.70 M and no NO(g) or O₂(g) initially present. At equilibrium the NO₂ concentration was found to be 0.28 M. Calculate K_c for the reaction.
2NO₂(g) 2NO(g) + O₂(g)

A) 0.47
B) 0.94
C) 1.9
D) 0.14
E) 2.1

Question 29

For the reaction below, 0.0500 moles of ethyl acetate are allowed to react with 0.200 moles of water. At equilibrium it is found that 0.0300 moles of acetic acid have been produced. How many moles of ethyl acetate remain at equilibrium?

A) 0.0100 moles
B) 0.0300 moles
C) 0.0500 moles
D) 0.170 moles
E) none of these

Question 30

A 0.100 M sample of SO₂ reacts with 0.060 M O₂ to produce SO₃ by the reaction shown below. There was no SO₃ present initially. The concentration of O₂ measured at equilibrium is found to be 0.020 M. What are the equilibrium concentrations of SO₂ and SO₃?

2 SO₂(g) + O₂(g) 2 SO₃(g)

A) [SO₂] = 0.040M, [SO₃] = 0.060M
B) [SO₂] = 0.080M, [SO₃] = 0.080M
C) [SO₂] = 0.080M, [SO₃] = 0.120M
D) [SO₂] = 0.020M, [SO₃] = 0.080M
E) none of these

Question 31

Calculate the concentrations of Cl₂ and ClF₃ at equilibrium if a reaction that initially contained 1.000 M concentrations of both Cl₂ and F₂ is found to have an F₂ concentration of 0.700 M at equilibrium.

A) [Cl₂] = 0.700M [ClF₃] = 0.700M
B) [Cl₂] = 0.700M [ClF₃] = 0.300M
C) [Cl₂] = 0.500M [ClF₃] = 0.300M
D) [Cl₂] = 0.900M [ClF₃] = 0.200M
E) none of these

Question 32

For the reaction
2 NOCl(g) 2 NO(g) + Cl₂   K_c = 5.6 x 10^-6   (at 400 K)

What is the relationship between the magnitude of the changes in the concentrations of NOCl and Cl₂ as this reaction comes to equilibrium?

A) [NOCl] = [Cl₂]
B) [NOCl] = 2 [Cl₂]
C) [Cl₂] = 2 [NOCl]
D) [NOCl] = 1/[Cl₂]
E) 2 [NOCl] = [Cl₂]

Question 33

What is the relationship between the changes in the concentration of NO₂ and O₂ as the following reaction comes to equilibrium?

2 NO₂(g) 2 NO(g) + O₂(g)   K_c = 7.4 x 10^-16   (at 25°C)

A) [NO₂] = -[O₂]
B) [NO₂] = -2 [O₂]
C) [O₂] = -2 [NO₂]
D) There is no relationship between the changes in the concentrations of these substances.
E) none of the above

Question 34

For the following reaction
2 C₂H₆(g) + 7 O₂(g) 4 CO₂(g) + 6 H₂O(g)

If the reaction mixture initially contained all species at the same initial concentration, C, and if the concentration of O₂ at equilibrium was expressed as [O₂] = C + 7 $\Delta$ C , then the concentration of H₂O at equilibrium would be correctly expressed as [H₂O] =

A) C + $\Delta$ C
B) C - $\Delta$ C
C) C + 6 $\Delta$ C
D) C - 6 $\Delta$ C
E) none of the above

Question 35

Calculate the COCl₂, CO, and Cl₂ concentrations when the following gas-phase reaction reaches equilibrium at 300°C.

Question 36

Calculate the NO, NO₂, and O₂ concentrations in the following gas-phase reaction at equilibrium at 200°C.

Question 37

Calculate the equilibrium concentrations of SO₃, SO₂, and O₂ if 0.100 moles of SO₃ in a 10-L flask decompose to form SO₂ and O₂ at 500 K.

2 SO₃(g) 2 SO₂(g) + O₂(g)   K_c = 1.4 x 10^-11

Question 38

Calculate the concentrations of all reactants and products when a mixture
that is initially 0.10 M in N₂, H₂, and NH₃ comes to equilibrium at 600 K.

N₂(g) + 3 H₂(g) 2 NH₃(g)   K_c = 0.045

Question 39

Assume an equilibrium constant K_c = 1.7 x 10^-2 for the reaction:

N₂(g) + 3 H₂(g) 2 NH₃(g)
Calculate (to a first approximation) the equilibrium concentrations of NH₃, H₂ and N₂ when 0.10 moles per liter each of N₂ and H₂ are mixed and allowed to react to equilibrium.

Question 40

Calculate the COCl₂, CO, and Cl₂ concentrations when the following gas-phase reaction reaches equilibrium at 300°C.

Question 41

Calculate the NO, NO₂, and O₂ concentrations in the following gas-phase reaction at equilibrium at 200°C.

Question 42

Hidden Assumptions that make Equilibrium Calculations Easier What Do We Do When the Approximation Fails?
based on the following reaction:

2H₂O(g) 2H₂(g) + O₂(g)
K_c = 2 x 10^-42 (at 25^oC)

-Starting with 0.10 M H₂O(g), what would be the best strategy for solving for the equilibrium concentrations of H₂O, H₂ and O₂?

A) Since the change in the concentrations are expected to be large going to equilibrium, the equation will have to be solved exactly.
B) Since the changes in the concentrations are expected to be large going to equilibrium, it is best to assume that all of the H₂O(g) is converted to products and then calculate the equilibrium concentration.
C) Since the changes in concentrations are expected to be small going to equilibrium, it is best to assume that the changes will be small relative to the initial concentration of H₂O(g).
D) Since the changes in concentrations are expected to be small going to equilibrium, it is best to assume that the changes will be large relative to the initial concentration of H₂O(g).
E) There is no reasonable way to even approximate the answer to this problem.

Question 43

Hidden Assumptions that make Equilibrium Calculations Easier What Do We Do When the Approximation Fails?
based on the following reaction:

2H₂O(g) 2H₂(g) + O₂(g)
K_c = 2 x 10^-42 (at 25^oC)

-Starting with only 0.10 M H₂O(g), which equation correctly shows the equilibrium concentrations of the reactants and products? ( $\Delta$ C represents the change in concentration of O₂(g))

A)
B)
C)
D)
E) None of the above

Question 44

Hidden Assumptions that make Equilibrium Calculations Easier What Do We Do When the Approximation Fails?
based on the following reaction:

2H₂O(g) 2H₂(g) + O₂(g)
K_c = 2 x 10^-42 (at 25^oC)

-The equation below solves for the change in concentration for the given reaction assuming the initial concentration of H₂O(g) is 0.10 M. Which equation will result if it is assumed that the change will be much smaller than the initial concentration of H₂O(g)?

A)
B)
C)
D)
E) None of the above

Question 45

Hidden Assumptions that make Equilibrium Calculations Easier What Do We Do When the Approximation Fails?
based on the following reaction:

2H₂O(g) 2H₂(g) + O₂(g)
K_c = 2 x 10^-42 (at 25^oC)

-When solving a problem with the initial conditions outlined below, we rearrange the problem to give an intermediate set of conditions where the concentration of one of the reactants or products is equal to zero.
Fe(CO)₅ Fe(CO)₄ + CO
Initial: 0.10 M   0.10 M 0.005 M
Our choice of whether to push the reaction all the way to the right or all the way to the left is determined by which of the following goals?

A) to make both Q_c and K_c large
B) to make both Q_c and K_c small
C) to bring Q_c as close as possible to K_c
D) to make the difference between Q_c and K_c as large as possible

Question 46

What would happen if F₂ was removed from the following reaction while it was at equilibrium?

Cl₂(g) + 3 F₂(g) 2 ClF₃(g)

A) The concentration of Cl₂ would increase as the reaction returned to equilibrium.
B) The concentration of both Cl₂ and F₂ would increase as the reaction returned to equilibrium.
C) The concentration of Cl₂ would decrease as the reaction returned to equilibrium.
D) The concentration of both Cl₂ and F₂ would decrease as the reaction returned to equilibrium.
E) The concentration of both F₂ and Cl₂ would remain the same because the reaction would be at equilibrium.

Question 47

What is the effect of increasing the temperature on the following exothermic reaction?

2 CO(g) + O₂(g) 2 CO₂(g)

A) The equilibrium will shift to the right.
B) The equilibrium will shift to the left.
C) The partial pressure of CO₂ will increase.
D) The partial pressure of O₂ will decrease.
E) It will have no effect.

Question 48

What would happen to the extent of the decomposition of PCl₅ at a given temperature if the pressure on the system were decreased by increasing the volume of the container at a constant temperature?

PCl₅(g) PCl₃(g) + Cl₂(g)

A) It would increase.
B) It would decrease.
C) It would remain constant.
D) Not enough information is given to determine this.

Question 49

Which of the following factors will cause this chemical reaction to shift its equilibrium to the right?

Xe(g) + 2 F₂(g) XeF₄(g)   $\Delta$ H = -218 kJ/mol_rxn

A) increasing the temperature
B) increasing the pressure
C) decreasing the pressure
D) increasing the concentration of XeF₄
E) decreasing the concentration of F₂

Question 50

The following chemical reaction has reached equilibrium. Which of the changes listed below would cause the equilibrium to shift back toward the reactants?
N₂(g) + 3 H₂(g) 2 NH₃(g)   $\Delta$ H = -92.2 kJ/mol_rxn

A) increasing the pressure
B) increasing the concentration of N₂
C) increasing the temperature
D) decreasing the concentration of NH₃
E) none of these

Question 51

The following reaction is at equilibrium. Which of the conditions listed below will cause the reaction to shift toward the products?
2 SO₃(g) + 2 Cl₂(g) 2 SO₂Cl₂(g)+ O₂(g)

A) The concentration of O₂ is increased.
B) The concentration of SO₂Cl₂ is decreased.
C) The concentration of SO₃ is decreased.
D) The pressure is decreased.
E) none of these

Question 52

The following reactions are at equilibrium. Beside each reaction is a change that is made to the system which may cause a shift in equilibrium. Which of the reactions will shift its equilibrium toward the products?

A) N₂(g) + O₂(g) 2 NO(g)   the concentration of NO is increased
B) PF₅(g) PF₃(g) + F₂(g)   the concentration of F₂ is increased
C) Cl₂(g) + 3 F₂(g) 2 ClF₃(g)   the concentration of Cl₂ is decreased
D) 2 SO₃(g) 2 SO₂(g) + O₂(g)   the concentration of SO₂ is decreased
E) none of these

Question 53

The following reactions are at equilibrium. Which of the reactions will shift its equilibrium toward the reactant side if the pressure is increased while holding the temperature constant?

A) 2 NO(g) + 2 H₂(g) N₂(g) + 2 H₂O(g)
B) 2 NOCl(g) 2 NO(g) + Cl₂(g)
C) 2 NO(g) + O₂(g) 2 NO₂(g)
D) N₂(g) + O₂(g) 2 NO(g)
E) NO(g) + NO₂(g) N₂O₃(g)

Question 54

What would happen if Cl₂ is added to the following system at equilibrium?
H₂(g) + Cl₂(g) 2 HCl(g)

A) The concentrations of both H₂ and HCl would remain the same.
B) The concentrations of both H₂ and HCl would increase.
C) The concentrations of both H₂ and HCl would decrease.
D) The concentration of H₂ would increase, but HCl would decrease.
E) The concentration of H₂ would decrease, but HCl would increase.

Question 55

Which of the following statements correctly describes the following reaction?
2 NH₃(g) N₂(g) + 3 H₂(g)   $\Delta$ H = 92.2 kJ

A) An increase in either pressure or temperature shifts the reaction to the left.
B) If the pressure of N₂ is doubled and a new equilibrium established, the concentration of H₂ at equilibrium will be reduced.
C) More ammonia will be present in the equilibrium mixture if a catalyst is added.
D) none of the above
E) all of the above

Question 56

What would be the effect of removing some NO₂ from the following system after the reaction reaches equilibrium at 25°C?

2 NO₂(g) 2 NO(g) + O₂(g)   K_c = 7.4 x 10^-16

A) The NO and O₂ concentrations would increase.
B) The NO and O₂ concentrations would decrease.
C) The NO concentration would increase but O₂ would decrease.
D) The O₂ concentration would increase but NO would decrease.
E) The concentrations of NO and O₂ would remain constant.

Question 57

The addition of I₂(g) to a fixed volume container with I₂(g), H₂(g), and HI(g) at equilibrium at a given temperature would cause

H₂(g) + I₂(g) 2 HI(g)

A) the concentrations of both H₂ and HI to decrease.
B) the concentrations of both H₂ and HI to increase.
C) the concentration of H₂ to increase and HI to decrease.
D) the concentration of H₂ to decrease and HI to increase.
E) Not enough information is given to determine how the concentrations will change.

Question 58

What would happen if O₂ were removed from the following system at equilibrium at 25°C?

2 NO₂(g) 2 NO(g) + O₂(g)   K_c = 7.4 x 10^-1 at 25^oC

A) The NO₂ and NO concentrations would increase.
B) The NO₂ and NO concentrations would decrease.
C) The NO₂ concentration would increase and the NO concentration would decrease.
D) The NO₂ concentration would decrease and the NO concentration would increase.
E) none of the above

Question 59

The equilibrium constant for the following reaction becomes larger as the temperature at which the reaction is run increases.

2 NOCl(g) 2 NO(g) + Cl₂(g)   K_c = 5.6 x 10^-6 at 400 K
What does this tell us about the reaction?

A) Heat is given off in the reaction.
B) Heat is absorbed in the reaction.
C) Heat is neither given off nor absorbed in the reaction.
D) Increasing the amount of NOCl would also increase the equilibrium constant for the reaction.
E) Increasing the amount of NO would also increase the equilibrium constant for the reaction.

Question 60

What is the effect of increasing the temperature on the following reaction?

2 CO(g) + O₂(g) 2 CO₂(g) + heat

A) The equilibrium will shift to the left.
B) The equilibrium will shift to the right.
C) The partial pressure of CO₂ will increase.
D) The partial pressure of O₂ will decrease.
E) It will have no effect.

Question 61

What would happen to the extent of the decomposition of PCl₅ at a given temperature if the pressure on the system were decreased?

PCl₅(g) PCl₃(g) + Cl₂(g)

A) It would increase.
B) It would decrease.
C) It would remain constant.
D) Not enough information is given to determine this.

Question 62

What would be the effect of decreasing the pressure on the following reaction after it reaches equilibrium?

2 NO₂(g) 2 NO(g) + O₂(g)

A) The NO and O₂ concentrations would increase.
B) The NO and O₂ concentrations would decrease.
C) The NO concentration would increase but O₂ would decrease.
D) The O₂ concentration would increase but NO would decrease.
E) The concentrations of NO and O₂ would remain constant.

Question 63

One of the products of the reaction between NO₂ and CO is CO₂. By writing the equation for the reaction (Hint: the coefficients for all reactants and products are 1), decide whether an increase in pressure:

A) favors CO₂ formation
B) decreases CO₂ formation
C) has no effect on CO₂ formation
D) cannot tell from information supplied

Question 64

Which of the following equilibria would not be affected by changes in pressure?

A) 2 NO(g) + O₂(g) 2 NO₂(g)
B) N₂O₄(g) 2 NO₂(g)
C) 4 NH₃(g) + 5 O₂(g) 4 NO(g) + 6 H₂O(g)
D) CaCO₃(s) CaO(s) + CO₂(g)
E) CO(g) + H₂O(g) CO₂(g) + H₂(g)

Question 65

What is the concentration in moles per liter of pure PbSO₄(s) given that it has a density of 6.29 g/cm³?

A) 6.29
B) 20.7
C) 1.00
D) 303
E) The concentration of a pure solid cannot be found.

Question 66

What is the correct solubility constant expression for PbSO₄?

A)
B) K_sp = [Pb²⁺][SO₂^2-][O₂]
C) K_sp = [Pb²⁺][SO₄^2-]
D)
E) none of the above

Question 67

Which is the correct reaction for the solubility constant expression (K_sp) of CaF₂(s)?

A) 2F^-_(aq) + Ca²⁺_(aq) CaF_2(s)
B) 2F_(aq) + Ca _(aq) CaF_2(s)
C) CaF_2(s) CaF_2(g)
D) CaF_2(s) Ca_(g) + 2F_(g)
E) CaF_2(s) Ca²⁺_(aq) + 2F^-_(aq)

Question 68

What is the correct solubility constant expression of Ba₃(PO₄)₂?

A)
B) K_sp = [Ba²⁺]²[PO₄^{3 -}]³
C) K_sp = [Ba²⁺][PO₄^{3 -}]
D) K_sp = [Ba²⁺]³[PO₄³ ]²
E) None of the above

Question 69

What is the correct solubility constant expression for CaF₂(s)?

A)
B) K_sp = [Ca²⁺]²[ ^- ]
C) K_sp = [Ca²⁺][ ^- ]
D) K_sp = [Ca²⁺][F₂]²
E) none of the above

Question 70

What is the correct solubility constant expression for AgCl(s)?

A) K_sp = [Ag⁺][Cl ^- ]
B) K_sp = [Ag⁺] + [Cl ^- ]
C) K_sp = [Ag⁺]/[Cl ^- ]
D) K_sp = [Ag][Cl]
E) none of the above

Question 71

What is the solubility in moles per liter of AgBr in water given that the K_sp is 5.0 x 10^-13?

A) 5.0 x 10 ^{- 13}
B) 2.5 x 10 ^{- 13}
C) 7.1 x 10 ^{- 7}
D) 4.0 x 10 ^{- 6}
E) 2.5 x 10 ^{- 7}

Question 72

What is the solubility in moles/L of CaF₂ in water given that the K_sp is 4.0 x 10 ^{- 11}?

A) 2.2 x 10 ^{- 4}
B) 4.0 x 10 ^{- 11}
C) 3.5 x 10 ^{- 4}
D) 6.0 x 10 ^{- 5}
E) 2.0 x 10 ^{- 11}

Question 73

If 1.3 x 10 ^{- 5} moles of AgCl will dissolve in 1.0 liter of water at 25-C, what is the K_sp of AgCl?

A) 5.1 x 10 ^{- 9}
B) 3.6 x 10 ^{- 3}
C) 6.4 x 10 ^{- 5}
D) 1.3 x 10 ^{- 5}
E) 1.7 x 10^-10

Question 74

If 6.5 x 10 ^{- 5} moles of Ag₂CrO₄ will dissolve in 1.0 liter of water at 25 C, what is the K_sp of Ag₂CrO₄?

A) 6.5 x 10 ^{- 5}
B) 4.2 x 10 ^{- 9}
C) 2.7 x 10 ^{- 13}
D) 1.1 x 10 ^{- 12}
E) 3.3 x 10 ^{- 5}

Question 75

If the K_sp of PbBr₂ is 8.9 x 10^-6, what is the solubility of PbBr₂(s) in moles/L?

A) 8.9 x 10 ^{- 6}
B) 1.3 x 10 ^-2
C) 3.3 x 10 ^{- 3}
D) 0.21
E) none of the above

Question 76

What is the fluoride ion concentration in a saturated solution of SrF₂ if the strontium ion concentration is 5.8 x 10 ^{- 4} M?

A) 5.8 x 10 ^{- 4}
B) 2.9 x 10 ^{- 4}
C) 1.2 x 10 ^{- 3}
D) 1.8 x 10 ^{- 3}
E) none of the above

Question 77

What is the K_sp of SrF₂(s) if 0.073 g of SrF₂ dissolves in 1.00 liter of solution?

A) 5.8 x 10 ^{- 4}
B) 1.7 x 10 ^{- 3}
C) 1.6 x 10 ^{- 3}
D) 7.8 x 10 ^{- 10}
E) none of the above

Question 78

What is the K_sp of PbBr₂ if the concentration of PbBr₂(aq) in a saturated solution is 1.3 x 10^-2 moles/L?

A) 8.8 x 10 ^{- 6}
B) 1.3 x 10 ^{- 2}
C) 3.9 x 10 ^{- 2}
D) 2.2 x 10 ^{- 2}
E) none of the above

Question 79

Which of the following equations correctly describes the relationship between the concentrations of Pb²⁺ and Br^- ions in a saturated solution of PbBr₂(s)?

A) [Pb²⁺] = 2[Br^-]
B) 2[Pb²⁺] = [Br^-]
C) [Pb²⁺] = [Br^-]
D) 3[Pb²⁺] = [Br^-]
E) none of the above

Question 80

Which of the following equations correctly describes the relationship between the concentrations of Sr²⁺ and PO₄^3- ions in a saturated solution of Sr₃(PO₄)₂(s)?

A) 3[Sr²⁺] = 2[PO₄^{3 -} ]
B) [Sr²⁺] = [PO₄^{3 -} ]
C) 2[Sr²⁺] = 3[PO₄^{3 -} ]
D) [Sr²⁺] = 2/3[PO₄^{3 -} ]
E) none of the above