Deck 15: Chemical Equilibrium

Question 1

A chemical system is considered to have reached dynamic equilibrium when

A)the frequency of collisions between the reactant molecules is equal to the frequency of collisions between the product molecules.
B)the sum of the concentrations of each of the reactant species is equal to the sum of the concentrations of each of the product species.
C)the activation energy of the forward reaction is equal to the activation energy of the reverse reaction.
D)the rate of production of each of the products is equal to the rate of their consumption by the reverse reaction.
E)the rate of production of each of the product species is equal to the rate of consumption of each of the reactant species.

Answer 1

the rate of production of each of the products is equal to the rate of their consumption by the reverse reaction.

Question 2

A chemical system is considered to have reached equilibrium when

A)the rate of consumption of each of the product species by the reverse reaction is equal to the rate of production of each of the reactant species by the reverse reaction.
B)the sum of the concentrations of each of the reactant species is equal to the sum of the concentrations of each of the product species.
C)the rate of production of each of the product species is equal to the rate of consumption of each of the product species by the reverse reaction.
D)the rate of production of each of the product species is equal to the rate of consumption of each of the reactant species by the reverse reaction.
E)the rate of production of each of the product species by the forward reaction is equal to the rate of production of each of the reactant species by the reverse reaction.

Answer 2

the rate of production of each of the product species is equal to the rate of consumption of each of the product species by the reverse reaction.

Question 3

Which statement about chemical equilibrium is not true?

A)At equilibrium, the reactant and the product concentrations show no further change with time.
B)Chemical equilibrium can only be attained by starting with reagents from the reactant side of the equation.
C)At equilibrium, the forward reaction rate equals the reverse reaction rate.
D)The same equilibrium state can be attained starting either from the reactant or product side of the equation.
E)At equilibrium, the reactant and product concentrations are constant.

Answer 3

Chemical equilibrium can only be attained by starting with reagents from the reactant side of the equation.

Question 4

Which of these statements are true about chemical equilibrium in general?

A)At equilibrium, the rate constant of the forward reaction is equal to the rate of the reverse reaction.
B)At equilibrium, the rate of the forward reaction is equal to the rate of the reverse reaction.
C)Equilibrium is the result of the cessation of all chemical change.
D)There is only one set of equilibrium concentrations that equals the K_c value.
E)At equilibrium the sum of the concentration of products equals the total concentration of the reactants.

Question 5

In a study of the system, H₂(g)+ I₂(g) 2 HI(g), at 699 K, several different reaction mixtures, described below, were prepared, placed in 5.00 liter containers, and allowed to attain equilibrium at 699 K. Despite having the different starting compositions shown, four of the five mixtures had the identical composition at equilibrium. Which one of the systems attained a different equilibrium composition than the others?

A)System 1: 0.100 moles of H₂, 0.000 moles of I₂ and 0.600 moles of HI
B)System 2: 0.175 moles of H₂, 0.075 moles of I₂ and 0.450 moles of HI
C)System 3: 0.400 moles of H₂, 0.300 moles of I₂ and 0.000 moles of HI
D)System 4: 0.150 moles of H₂, 0.100 moles of I₂ and 0.500 moles of HI
E)System 5: 0.300 moles of H₂, 0.200 moles of I₂ and 0.200 moles of HI

Question 6

Given the two reactions shown with their equilibrium constants, What is the equilibrium constant for the reaction,PCl₅(g)+ 2 NO(g) PCl₃(g)+ 2 NOCl(g)

A)K₁K₂
B)K₂/K₁
C)K₁/K₂
D)(K₁K₂)^?1
E)K₂ ? K₁

Question 7

In a study of the system, Cl₂(g)+ Br₂(g) 2 BrCl(g), at 350 K, several different reaction mixtures, described below, were prepared, placed in 5.00 liter containers, and allowed to attain equilibrium at 350 K. Despite having the different starting compositions shown, four of the five mixtures had the identical composition at equilibrium. Which one of the systems attained a different equilibrium composition than the others?

A)System 1: 0.100 moles of Cl₂, 0.000 moles of Br₂ and 0.600 moles of BrCl
B)System 2: 0.250 moles of Cl₂, 0.150 moles of Br₂ and 0.300 moles of BrCl
C)System 3: 0.400 moles of Cl₂, 0.300 moles of Br₂ and 0.000 moles of BrCl
D)System 4: 0.300 moles of Cl₂, 0.250 moles of Br₂ and 0.250 moles of BrCl
E)System 5: 0.350 moles of Cl₂, 0.250 moles of Br₂ and 0.100 moles of BrCl

Question 8

In a study of the system, N₂O₄(g) 2 NO₂(g), at 585 K, several different reaction mixtures, described below, were prepared, placed in 5.00 liter containers, and allowed to attain equilibrium at 480 K. Despite having different starting compositions shown, four of the five mixtures had the identical composition at equilibrium. Which one of the systems attained a different equilibrium composition than the others?

A)System 1: 0.400 moles of N₂O₄ and 0.800 moles of NO₂
B)System 2: 0.300 moles of N₂O₄ and 1.000 moles of NO₂
C)System 3: 0.800 moles of N₂O₄ and 0.000 moles of NO₂
D)System 4: 0.600 moles of N₂O₄ and 0.400 moles of NO₂
E)System 5: 0.400 moles of N₂O₄ and 0.700 moles of NO₂

Question 9

In a study of the system, Cl₂(g)+ 2 NO(g) 2 NOCl(g), at 425 K, several different reaction mixtures, described below, were prepared, placed in 5.00 liter containers, and allowed to attain equilibrium at 425 K. Despite having different starting compositions shown, four of the five mixtures had the identical composition at equilibrium. Which one of the systems attained a different equilibrium composition than the others?

A)System 1: 0.100 moles of Cl₂, 0.000 moles of NO and 0.600 moles of NOCl
B)System 2: 0.250 moles of Cl₂, 0.300 moles of NO and 0.300 moles of NOCl
C)System 3: 0.400 moles of Cl₂, 0.600 moles of NO and 0.000 moles of NOCl
D)System 4: 0.300 moles of Cl₂, 0.250 moles of NO and 0.250 moles of NOCl
E)System 5: 0.350 moles of Cl₂, 0.500 moles of NO and 0.100 moles of NOCl

Question 10

Which of the following is the correct equilibrium law for the following reaction?N₂H₄(g)+ 6H₂O₂(g) 2(g)+ 8H₂O(g)

A)K_c =

B)K_c = [NO₂]²[H₂O]⁸[N₂H₄] [H₂O₂]⁶
C)K_c = [NO₂] [H₂O] [N₂H₄] [H₂O₂]
D)K_c =

E)K_c =

Question 11

Which of the following is the correct equilibrium law for the following reaction?N₂(g)+ 3H₂(g) 2NH₃(g)

A)K_c =

B)K_c = [NH₃]²[N₂] [H₂]³
C)K_c = [NH₃] [N₂] [H₂]
D)K_c =

E)K_c =

Question 12

Given the two reactions shown with their equilibrium constants, What is the equilibrium constant for the reaction,PCl₃(g)+ NO₂(g) POCl₃(g)+ NO(g)

A)K₁K₂
B)K₂/K₁
C)K₁/K₂
D)(K₁K₂)^-1
E)K₂ - K₁

Question 13

Consider the following reactions and their associated equilibrium constants: For the reaction A + 2B D + E, having equilibrium constant K_c,

A)K_c = (K₁)(K₂)
B)K_c = K₂/K₁
C)K_c = K₁/K₂
D)K_c = K₁ -K₂
E)K_c = K₁ + K₂

Question 14

The equilibrium constant for the reaction, H₂(g)+ I₂(g) 2 HI(g)is 54.9 at 699.0 K. What is the equilibrium constant for 4 HI(g) 2 H₂(g)+ 2 I₂(g)under the same conditions?

A)109.8
B)0.00911
C)0.000332
D)?109.8
E)0.0182

Question 15

For a specific reaction, which statement can be made about the equilibrium constant?

A)It can change with temperature.
B)It may be changed by addition of a catalyst.
C)It increases if the concentration of one of the products is increased.
D)It increases if the concentration of one of the products is decreased.
E)It always remains the same.

Question 16

Using this data, calculate a value for K_c for the reaction,NOCl(g)+ ½ O₂(g) NO₂(g)+ ½ Cl₂(g)

A)2.06 × 10^-4
B)4.84 × 10^-3
C)0.223
D)4.49
E)20.2

Question 17

For the reaction, 2SO₂(g)+ O₂(g) 2SO₃(g), at 900.0 K the equilibrium constant, K_c, has a value of 13.0. Calculate the value of K_p at the same temperature.

A)97.3 × 10³
B)0.176
C)960
D)0.00174
E)0.077

Question 18

A student is preparing a study of the reaction, 2CO₂(g) 2CO(g)+ O₂(g), for which at 827 °C. What is the value of K_p at that same temperature?

A)2.90 × 10^-1
B)3.86 × 10^-1
C)1.78 × 10³
D)2.37 × 10³
E)2.40 × 10⁵

Question 19

For which one of the following reactions is K_p equal to K_c?

A)4NH₃(g)+ 5O₂(g) 4NO(g)+ 6H₂O(g)
B)C(s)+ CO₂(g) 2CO(g)
C)6CO₂(g)+ 6H₂O(l) C₆H₁₂O₆(s)+ 6O₂(g)
D)CaCO₃(s) CaO(s)+ CO₂(g)
E)H₂O(g)+ C(s) H₂(g)+ CO(g)

Question 20

For which one of the following reactions is K_p equal to K_c?

A)3O₂(g) 2O₃(g)
B)2NH₃(g) 3H₂(g)+ N₂(g)
C)CaCO₃(s) CaO(s)+ CO₂(g)
D)NH₄I(s) NH₃(g)+ HI(g)
E)SnO₂(s)+ 2H₂(g) Sn(s)+ 2H₂O(g)

Question 21

The concentration of a pure solid or a pure liquid is left out of the expression for the equilibrium constant because

A)solids and liquids drive the reaction in an undetermined fashion.
B)solids and liquids do not react.
C)their concentrations cannot be determined.
D)solids and liquids react too slowly.
E)their activity is constant and independent of the amount of solid or liquid present.

Question 22

Write the mass action expression for the following reaction:4Cr(s)+ 3CCl₄(g) 4CrCl₃(g)+ 4C(s)

A)K_c =

B)K_c =

C)K_c =

D)K_c =

E)K_c = [CrCl₃]⁴ + [CCl₄]³

Question 23

The equilibrium law for the system, CaO(s)+ CO₂(g) CaCO₃(s), is

A)K_c = [CO₂].
B)K_c = [CaCO₃]/([CaO] [CO₂]).
C)K_c = 1/[CO₂].
D)K_c = [CaCO₃]/[CaO].
E)K_c = ([CaO] [CO₂])/[CaCO₃].

Question 24

For the chemical reaction, N₂(g)+ 3H₂(g) 2NH₃(g),K_c = 4.2 × 10² at some temperature that we call T₁. 4.00 moles of NH₃ were placed in a 50.0-liter container at T₁ and allowed to come to equilibrium. Which situation below is true at equilibrium?

A)[NH₃] = 3 × [H₂]
B)[NH₃] > [H₂]
C)[H₂] > [NH₃]
D)[NH₃] = [H₂]
E)[N₂] = [NH₃]

Question 25

The equilibrium constant for the reaction, R₂ D₂ is 6.8 × 10^?10. Which one of the following statements is true?

A)The equilibrium concentration of D₂ is always greater than that of R₂.
B)The equilibrium concentration of R₂ is always greater than that of D₂.
C)Adding more R₂ will increase the value of the equilibrium constant.
D)Adding a catalyst will increase the equilibrium concentration of D₂.
E)Adding a catalyst will increase the value of the equilibrium constant.

Question 26

The following reactions occur at 298 K. Arrange them in order of increasing tendency to proceed to completion (least completion ? greatest completion)

A)3 < 1 < 2 < 4
B)4 < 2 < 1 < 3
C)4 < 3 < 2 < 1
D)4 < 2 < 3 < 1
E)3 < 2 < 4 < 1

Question 27

The following reactions occur at 298 K. Arrange them in order of increasing tendency to proceed to completion (least completion ? greatest completion).

A)1 < 2 < 4 < 3
B)3 < 1 < 2 < 4
C)3 < 4 < 2 < 1
D)1 < 3 < 2 < 4
E)4 < 1 < 2 < 3

Question 28

For a system, H₂(g)+ I₂(g) 2 HI(g), K_c = 62.9 at 750 K. 2.80 moles of HI were placed in a 10.0-liter container, it was brought up to 750 K, and allowed to come to equilibrium. Which situation described below is true, at equilibrium?

A)[HI] = 2 × [H₂]
B)[HI] = [H₂]
C)[HI] < [H₂]
D)[HI] > [H₂]
E)[H₂] > [I₂]

Question 29

The following reactions have equilibrium values all measured at 500 K. Arrange them in order of increasing tendency to proceed to completion (least completion ? greatest completion).

A)2 < 1 < 3 < 4
B)4 < 3 < 1 < 2
C)3 < 1 < 4 < 2
D)3 < 4 < 1 < 2
E)4 < 3 < 2 < 1

Question 30

For the reaction, 2SO₂(g)+ O₂(g) 2SO₃(g), at 450.0 K the equilibrium constant, K_c, has a value of 4.62. A system was charged to give these initial concentrations, [SO₃] = 0.254 M, [O₂] = 0.00855 M, [SO₂] = 0.500 M. In which direction will it go? Hint: Find the value for Q and then compare that value to the given value for K_c.

A)to the right or the left depending on the pressure
B)to the left
C)it will remain at the same concentrations
D)to the right
E)to the right or the left depending on the volume

Question 31

For the reaction, 2SO₂(g)+ O₂(g) 2SO₃(g), at 450.0 K the equilibrium constant, K_c, has a value of 4.62. A system was charged to give these initial concentrations: [SO₃] = 0.500 M, [O₂] = 0.00855 M, [SO₂] = 0.254 M. In which direction will it go?Hint: Find the value for Q and then compare that value to the given value for K_c

A)to the right
B)it will remain at the same concentrations
C)to the left
D)to the right or the left depending on the pressure
E)to the right or the left depending on the volume

Question 32

For the reaction, 2SO₂(g)+ O₂(g) 2SO₃(g), at 450.0 K the equilibrium constant, K_c, has a value of 4.62. A system was charged to give these initial concentrations: [SO₃] = 0.0254 M, [O₂] = 0.00855 M, [SO₂] = 0.500 M. In which direction will it go? Hint: Find the value for Q and then compare that value to the given value for K_c

A)to the right
B)to the left
C)to the right or the left depending on the pressure
D)it will remain at the same concentrations
E)to the right or the left depending on the volume

Question 33

Given the reaction, 2NO(g)+ O₂(g) 2NO₂(g), for which the enthalpy of reaction is -118.9 kJ .Which one of the following actions will cause an increase in the equilibrium concentration of NO(g)in a closed reaction chamber?

A)adding more O₂(g)through an injection nozzle
B)increasing the temperature of the system
C)removing the NO₂(g)from the system
D)increasing the pressure of the system while temperature is kept constant
E)adding a catalyst

Question 34

The reaction, 2 SO₃(g) 2 SO₂(g)+ O₂(g)is endothermic. Predict what will happen if the temperature is increased.

A)K_c remains the same.
B)K_c decreases.
C)The pressure decreases.
D)More SO₃(g)is produced.
E)K_c increases.

Question 35

Consider the following system, which is at equilibrium,CO(g)+ 3H₂(g) CH₄(g)+ H₂O(g).The result of removing some CH₄(g)and H₂O(g)from the system is that

A)more CH₄(g)and H₂O(g)are produced to replace that which is removed.
B)K_c decreases.
C)more CO(g)is produced.
D)more H₂O(g)is consumed to restore the equilibrium.
E)more CH₄(g)is consumed to restore the equilibrium.

Question 36

Consider the following system, which is at equilibrium, 3C(s)+ 3H₂(g) CH₄(g)+ C₂H₂(g)The result of removing some CH₄(g)and C₂H₂(g)from the system is that

A)no further change occurs.
B)K_c increases.
C)more C(s)is produced.
D)more C₂H₂(g)is consumed to restore the equilibrium.
E)more CH₄(g)and C₂H₂(g)are produced to replace that which is removed.

Question 37

Consider the following system, which is at equilibrium, 3C(s)+ 3H₂(g) CH₄(g)+ C₂H₂(g)The result of removing some C(s)from the system will be:

A)K_c increases.
B)more C(s)is produced.
C)no further change occurs.
D)more CH₄(g)and C₂H₂(g)are produced to restore the equilibrium.
E)more C₂H₂(g)is consumed to restore the equilibrium.

Question 38

The system, 2H₂O(g)+ 2Cl₂(g) 4HCl(g)+ O₂(g), has a value of 8.00 for K_p. Initially, the partial pressures of H₂O(g)and Cl₂(g)are set at 0.100 atm, while those of HCl(g)and O₂(g)are set at 0.250 atm. Which statement below is true?

A)Q_p > K_p and the reaction proceeds to the right to reach equilibrium.
B)Q_p < K_p and the reaction proceeds to the left to reach equilibrium.
C)The reaction system is already at equilibrium.
D)Q_p > K_p and the reaction proceeds to the left to reach equilibrium.
E)Q_p < K_p and the reaction proceeds to the right to reach equilibrium.

Question 39

The system, H₂(g)+ X₂(g) 2HX(g)has a value of 24.4 for K_c. A system being studied in a 3.00 liter reactor was charged with 0.150 moles of H₂, 0.150 moles of X₂, and 0.600 moles of HX. A catalyst was introduced using a remote unit. Which statement below describes the situation? Hint: Be sure to find molarities of all reactants and products before calculating Q.

A)The reaction goes to the right, Q < K.
B)The reaction goes to the left, Q < K.
C)The reaction goes to the right, Q > K.
D)The reaction goes to the left, Q > K.
E)It is not possible to predict in which direction the system will travel as it reacts.

Question 40

A study of the system, 4NH₃(g)+ 7O₂(g) 2N₂O₄(g)+ 6H₂O(g), was carried out. A system was prepared with [NH₃] = [O₂] = 3.60 M as the only components initially. At equilibrium, [N₂O₄] is 0.60 M. Calculate the equilibrium concentration of O₂. Hint: Organize your information using an ICE table, then use the equilibrium N₂O₄ concentration to find the concentration of O₂.

A)3.00 M
B)2.40 M
C)1.50 M
D)2.10 M
E)3.30 M

Question 41

A study of the system, 4NH₃(g)+ 5O₂(g) 4NO(g)+ 6H₂O(g), was carried out. A system was prepared with [NH₃] = [O₂] = 5.60 M as the only components initially. At equilibrium, [NO] is 0.36 M. Calculate the equilibrium concentration of O₂.Hint: Organize your information using an ICE table, then use the equilibrium NO concentration to find the concentration of O₂.

A)6.05 M
B)5.15 M
C)5.24 M
D)0.60 M
E)5.51 M

Question 42

NH₂CO₂NH₄(s)undergoes the following reaction at 450 K to produce a system thatreaches equilibrium:NH₂CO₂NH₄(s) 2NH₃(g)+ CO₂(g)The total pressure in the closed container under these conditions is found to be 0.843 atm. Calculate a value for the equilibrium constant, K_p.Hint: Organize your information using an ICE table, then use Dalton's Law to find the equilibrium pressures of each product gas.

A)0.00701
B)0.0888
C)0.222
D)0.599

Question 43

For the reaction system, 2SO₂(g)+ O₂(g) 2SO₃(g), the equilibrium concentrations are: SO₃: 0.120 M SO₂: 0.860 M O₂: 0.330 M Calculate the value of K_c for this reaction.

A)1.31
B)2.51
C)0.423
D)0.872
E)0.0590

Question 44

For the reaction system, H₂(g)+ X₂(g) 2HX(g), K_c = 24.4 at 300 K. A system made up from these components which is at equilibrium contains 0.150 moles of H₂ and 0.600 moles of HX in a 3.00-liter container. Calculate the number of moles of X₂(g)present at equilibrium. Hint: Be sure to find molarities of all reactants and products before finding the equilibrium amount of X₂.

A)0.0984 mol
B)0.164 mol
C)0.0328 mol
D)0.131 mol
E)0.393 mol

Question 45

For the reaction system, H₂(g)+ X₂(g) 2HX(g), K_c = 24.4 at 300 K. A system made up from these components that is at equilibrium contains 0.200 moles of X₂ and 0.600 moles of HX(g)in a 4.00 liter container. Calculate the number of moles of H₂(g)present at equilibrium. Hint: Be sure to find molarities of all reactants and products before finding the equilibrium amount of H₂.

A)0.059 mol
B)0.074 mol
C)0.123 mol
D)0.148 mol
E)0.295 mol

Question 46

For the reaction system, 2SO₂(g)+ O₂(g) 2SO₃(g), K_c has a value of 4.62 at 450.0 K. A system, at equilibrium, was found to contain 0.360 moles of SO₂ and 0.900 moles of O₂ in a 3.00 liter container. Calculate the number of moles of SO₃ gas at equilibrium. Hint: Be sure to find molarities of all reactants and products before finding the equilibrium amount of SO₃.

A)0.166 M
B)0.734 M
C)0.539 M
D)0.424 M
E)0.141 M

Question 47

For the reaction system, 2SO₂(g)+ O₂(g) 2SO₃(g), K_c has a value of 4.62 at 450.0 K. A system, at equilibrium, was found to contain 0.440 moles of SO₂ and 0.880 moles of O₂ in a 4.00 liter container. Calculate the number of moles of SO₃ gas at equilibrium. Hint: Find molarities of all reactants and products before finding the equilibrium amount of SO₃.

A)0.443 M
B)0.887 M
C)0.0492 M
D)0.111 M
E)0.0123 M

Question 48

At 1500 °C the system, 2NO(g) N₂(g)+ O₂(g), was allowed to come to equilibrium. The equilibrium concentrations were: NO(g)= 0.00035 M, N₂(g)= 0.040 M, and O₂(g)= 0.040 M. What is the value of K_c for the system at this temperature?

A)3.3 × 10⁴
B)7.7 × 10^-5
C)2.2 × 10^-1
D)4.6
E)1.3 × 10⁴

Question 49

For the reaction system, 2SO₂(g)+ O₂(g) 2SO₃(g), K_c has a value of 4.62 at 450.0 K. A system, at equilibrium, has the following concentrations: [SO₃] = 0.254 M, [O₂] = 0.00855 M. What is the equilibrium concentration of SO₂(g)?

A)1.28 M
B)0.216 M
C)0.465 M
D)6.43 M
E)41.3 M

Question 50

For the reaction, H₂(g)+ I₂(g) 2HI(g), K_c = 54.9 at 699.0 K. A system, at equilibrium, contains 2.50 moles of HI(g)and 2.12 moles of I₂(g)in a 5.00 liter vessel. How many moles of H₂(g)should there be in the container? Hint: Be sure to find molarities of all reactants and products before finding the equilibrium amount of H₂.

A)0.0537 moles
B)0.380 moles
C)0.0215 moles
D)0.0107 moles
E)2.12 moles

Question 51

The system, 2NO(g) N₂(g)+ O₂(g)was allowed to come to equilibrium at 1500 °C. The equilibrium concentrations were: NO(g)= 0.00035 M, N₂(g)= 0.040 M, and O₂(g)= 0.040 M. What is the value of K_p for the system at this temperature?

A)2.2 × 10^-1
B)1.3 × 10⁴
C)3.3 × 10³
D)4.6
E)1.5

Question 52

For the reaction, 2BrCl(g) Cl₂(g)+ Br₂(g), K_p has a value of 0.140 at 350 K. In a container housing this system, the [Cl₂(g)] = [Br₂(g)] = 0.0200 M at equilibrium. What is the value of the partial pressure of BrCl_(g)? Hint: The ideal gas law is needed to convert molarity to pressure.

A)2.86 × 10^-3 atm
B)5.35 × 10^-2 atm
C)8.21 × 10^-2 atm
D)1.25 × 10^-5 atm
E)1.54 atm

Question 53

A study of the system, 4NH₃(g)+ 7O₂(g) 2N₂O₄(g)+ 6H₂O(g), was carried out. A system was prepared with [NH₃] = [O₂] = 3.60 M as the only components initially. At equilibrium, [N₂O₄] is 0.600 M. Calculate the equilibrium concentration of NH₃(g).Hint: Organize your information using an ICE table, then use the equilibrium N₂O₄ concentration to find the concentration of NH₃.

A)3.00 M
B)2.10 M
C)3.30 M
D)1.80 M
E)2.40 M

Question 54

A study of the system, 4NH₃(g)+ 7O₂(g) 2N₂O₄(g)+ 6H₂O(g), was carried out. A system was prepared with [N₂O₄] = [H₂O] = 3.60 M as the only components initially. At equilibrium, [H₂O] is 0.600 M. Calculate the equilibrium concentration of NH₃(g). Hint: Organize your information using an ICE table, then use the equilibrium H₂O concentration to find the concentration of NH₃.

A)1.50 M
B)0.90 M
C)3.00 M
D)2.40 M
E)2.00 M

Question 55

A study of the following system, 4 NH₃(g)+ 7 O₂(g) 2 N₂O₄(g)+ 6 H₂O(g), was carried out. A system was prepared with [N₂O₄] = [H₂O] = 3.60 M as the only components initially. At equilibrium, [H₂O] is 0.600 M. Calculate the equilibrium concentration of O₂(g). Hint: Organize your information using an ICE table, then use the equilibrium H₂O concentration to find the concentration of O₂.

A)0.700 M
B)3.00 M
C)1.00 M
D)2.40 M
E)3.50 M

Question 56

A vessel was filled with NOCl gas until the concentration was 0.398 mol/liter. The temperature of the system was increased to 245 °C and the system was allowed to undergo the reaction, , until equilibrium was attained. The physical chemistry students did a calculation and found the [Cl₂] at that point was 0.0225 mol/liter. Calculate the value of K_c at that temperature.

A)2.87 × 10^-3
B)3.66 × 10^-4
C)8.13 × 10^-3
D)1.29 × 10^-4
E)9.14 × 10^-5

Question 57

A study of the system, 4 NH₃(g)+ 7 O₂(g) 2 N₂O₄(g)+ 6 H₂O(g), was carried out. A system was prepared with [NH₃] = [O₂] = 3.60 M as the only components initially. At equilibrium, [N₂O₄] is 0.60 M. Calculate the value of the equilibrium constant, K_c, for the reaction.Hint: Organize your information using an ICE table, then use the equilibrium N₂O₄ concentration to find the concentrations of all reactants and products to find K_c.

A)8.1
B)0.0000093
C)0.30
D)0.022
E)3.3

Question 58

A study of the system, H₂(g)+ I₂(g) 2HI(g), was carried out. K_c = 54.9 at 699.0 K for this reaction. A system was charged with 2.50 moles of HI in a 5.00-liter vessel as the only component initially. The system attained equilibrium at 699.0 K. How many moles of H₂(g)should there be in the container at that time?Hint: Be sure to find molarities of all reactants and products before plugging in to the equilibrium law and solving for the amount of H₂.

A)0.337 moles
B)1.25 moles
C)0.297 moles
D)0.500 moles
E)0.266 moles

Question 59

A study of the system, H₂(g)+ I₂(g) 2HI(g), was carried out. K_c = 54.9 at 699.0 K for this reaction. A system was charged with 2.50 moles of H₂(g)and 2.50 moles I₂(g)in a 5.00 liter vessel as the only components initially. The system attained equilibrium at 699.0 K. How many moles of H₂(g)should there be in the container at that time?Hint: Be sure to find molarities of all reactants and products before plugging in to the equilibrium law and solving for the amount of H₂.

A)0.531 moles
B)0.674 moles
C)0.594 moles
D)1.00 moles
E)0.266 moles

Question 60

A student was assigned to carry out some calculations regarding the system described by the equation, I₂(g)+ Br₂(g) 2IBr(g). K_c = 250 for this system. The system was to be charged with 0.0500 M of I₂ and of Br₂, then allowed to attain equilibrium at the desired temperature. What value should the student obtain for the equilibrium concentration of IBr(g)?Hint: Organize your information using an ICE table, then use the equilibrium law to find the concentration of IBr.

A)0.0056 M
B)0.0444 M
C)0.0888 M
D)0.0950 M
E)0.100 M

Question 61

For the system, H₂(g)+ I₂(g) 2HI(g), K_c = 24.4 at 300 K. A system was charged with 2.00 moles of HI in a 3.00-liter container. The catalyst was introduced using a remote unit, and the system was allowed to come to equilibrium. How many moles of H₂(g)will be present when the system reaches equilibrium? Hint: Organize your information using an ICE table, then use the equilibrium expression to find the equilibrium amount of H₂.

A)0.288 moles
B)0.337 moles
C)0.388 moles
D)0.404 moles
E)0.424 moles

Question 62

For the system, H₂(g)+ I₂(g) 2HI(g), K_c = 24.4 at 300 K. A system was charged with 1.00 moles of H₂(g)and 1.00 moles of I₂(g)in a 3.00 liter container. The catalyst was introduced using a remote unit, and the system was allowed to come to equilibrium. How many moles of H₂(g)will be present when the system reaches equilibrium? Hint: Organize your information using an ICE table, then use the equilibrium expression to find the equilibrium amount of H₂.

A)0.288 moles
B)0.337 moles
C)0.388 moles
D)0.404 moles
E)0.442 moles

Question 63

By convention, the ________ are always written on the left side of an equilibrium expression.

Question 64

When the direction of an equation is ________, the new equilibrium constant is the reciprocal of the original.

Question 65

For a given equilibrium process A + B C + D the value of K_c was found to be equal to 3.2 × 10⁻⁴. Therefore, the reaction favors ________.

Question 66

Write the equilibrium law for the reaction,SO₂Cl₂(g)+ 2NO(g) SO₂(g)+ 2NOCl(g)

Question 67

The equilibrium law for a reaction in which all the components are gases is: = K_cWrite the balanced equation for the reaction described by this equilibrium constant.

Question 68

Write the equilibrium law for the reaction,2AsF₃(g)+ 3CCl₄(g) 2AsCl₃(g)+ 3CCl₂F₂(g)

Question 69

Write the equilibrium law, in terms of K_c, for the reaction,N₂H₄(g)+ 6H₂O₂(g) 2NO₂(g)+ 8H₂O(g)

Question 70

Write the equilibrium law, in terms of K_c, for the following chemical reaction:Ni²⁺(aq)+ 6NH₃(aq)→ [Ni(NH₃)₆]²⁺(aq)

Question 71

Write the equilibrium law, in terms of K_p, for the reaction below.CH₄(g)+ 2NO₂(g) CO₂(g)+ 2H₂O(g)+ N₂(g)

Question 72

Write the expression for K_p, for the reaction,N₂(g)+ O₂(g) 2NO(g)

Question 73

Write the expression for K_p, for the reaction,CO(g)+ 2H₂(g) CH₃OH(g)

Question 74

Write the expression for K_p, for the reaction,4HCl(g)+ O₂(g) 2H₂O(g)+ 2Cl₂(g)

Question 75

Write the expression for K_p, for the reaction,SnCl₂(s)+ Cl₂(g) SnCl₄(g)

Question 76

Write the expression for K_p, for the reaction,NH₄Cl(s) NH₃(g)+ HCl(g)

Question 77

Write the expression for K_c, for the reaction,4Cr(s)+ 3CCl₄(g) 4CrCl₃(g)+ 4C(s)

Question 78

Write the expression for K_c, for the reaction,C(s)+ H₂O(g) HCHO(g)

Question 79

Write the equilibrium law for the following chemical reaction:TiO₂(s)+ C(s)+ 2Cl₂(g)→ TiCl₄(g)+ CO₂(g)

Question 80

Write the equilibrium law for the following chemical reaction:Ni(H₂O)₆²⁺(aq)+ 5NH₃(aq)→ Ni(NH₃)₅(H₂O)²⁺(aq)+ 5H₂O(l)