Deck 16: Chemical Equilibrium

Question 1

What equilibrium constant applies to an aqueous solution of a weak acid or a weak base?

A)general equilibrium constant,Keq
B)ionization equilibrium constant,Ki
C)ionization equilibrium constant,Kw
D)solubility product equilibrium constant,Ksp
E)none of the above

Answer 1

ionization equilibrium constant,Ki

Question 2

What is the term for a type of equilibrium in which F all of the participating species are in the same physical state?

A)concentration equilibrium
B)heterogeneous equilibrium
C)homogeneous equilibrium
D)physical equilibrium
E)none of the above

Answer 2

homogeneous equilibrium

Question 3

What is the term for the energy necessary for reactants to achieve the transition state and form products?

A)activation energy
B)collision energy
C)heat of reaction
D)energy barrier
E)rate barrier

Answer 3

activation energy

Question 4

What is the term for the change in concentration of reactants per unit time?

A)rate of change
B)rate of reaction
C)reactant profile
D)reaction profile
E)none of the above

Question 5

What law states that the following relationship for a reversible reaction at equilibrium is equal to a constant: [C]c [D]d / [A]a [B]b?

A)law of chemical equilibrium
B)law of heterogeneous equilibrium
C)law of homogeneous equilibrium
D)law of molecular equilibrium
E)none of the above

Question 6

What equilibrium constant applies to an aqueous solution of a slightly dissociated ionic compound?

A)general equilibrium constant,Keq
B)ionization equilibrium constant,Ki
C)ionization equilibrium constant,Kw
D)solubility product equilibrium constant,Ksp
E)none of the above

Question 7

Which of the following influences the rate of a chemical reaction?

A)collision frequency
B)collision energy
C)collision orientation
D)all of the above
E)none of the above

Question 8

What is the term for a substance that allows a reaction to proceed faster by lowering the energy of activation?

A)activation energy
B)collision energy
C)energy barrier
D)catalyst
E)rate barrier

Question 9

Which principle states that a reversible reaction at equilibrium will shift to relieve the stress by a change in concentration,temperature,or pressure?

A)equilibrium principle
B)Le Chatelier's principle
C)Guldberg's principle
D)Waage's principle
E)none of the above

Question 10

What equilibrium constant applies to a reversible reaction involving a gaseous mixture at equilibrium?

A)general equilibrium constant,Keq
B)ionization equilibrium constant,Ki
C)ionization equilibrium constant,Kw
D)solubility product equilibrium constant,Ksp
E)none of the above

Question 11

Which of the following increases the collision frequency of molecules?

A)increasing the concentration
B)decreasing the temperature
C)adding a catalyst
D)all of the above
E)none of the above

Question 12

What is the term for a dynamic state of a reversible reaction in which the rates of the forward and reverse reactions are equal?

A)chemical equilibrium
B)concentration equilibrium
C)dynamic equilibrium
D)rate equilibrium
E)reversible equilibrium

Question 13

What is the term for a type of equilibrium in which F all of the participating species are not in the same physical state?

A)concentration equilibrium
B)heterogeneous equilibrium
C)homogeneous equilibrium
D)physical equilibrium
E)none of the above

Question 14

What is the term for a reaction that proceeds simultaneously in the forward direction toward products,as well as in the opposite direction toward reactants?

A)acid-base reaction
B)amphiprotic reaction
C)converse reaction
D)reversible reaction
E)none of the above

Question 15

What is the term for a reaction that proceeds by releasing heat energy?

A)endothermic reaction
B)exothermic reaction
C)isothermal reaction
D)all of the above
E)none of the above

Question 16

What is the term for the highest point on the reaction profile at which reactants and products have the greatest energy?

A)equilibrium state
B)product state
C)reactant state
D)transition state
E)none of the above

Question 17

What is the term for the graph of the energy of reactants and products as the reaction progresses?

A)endothermic profile
B)exothermic profile
C)reactant profile
D)reaction profile
E)none of the above

Question 18

What is the term for the difference in heat energy between the reactants and the products for a given chemical reaction?

A)activation energy
B)endothermic
C)exothermic
D)heat of reaction
E)none of the above

Question 19

What is the term for a reaction that proceeds by absorbing heat energy?

A)endothermic reaction
B)exothermic reaction
C)isothermal reaction
D)all of the above
E)none of the above

Question 20

What is the term for the principle that the rate of reaction is regulated by the frequency,energy,and orientation of molecules striking each other?

A)collision theory
B)energy theory
C)frequency theory
D)orientation theory
E)rate theory

Question 21

Refer to the following graphs to answer the question(s)below.
What is the reaction profile for: 3 O₂(g)+ heat 2 O₃(g)?

A)Graph (a)
B)Graph (b)
C)Graph (c)
D)Graph (d)
E)Graph (e)

Question 22

Which of the following factors increases the rate of a chemical reaction?

A)decreasing the concentration
B)decreasing the temperature
C)adding a catalyst
D)all of the above
E)none of the above

Question 23

Which of the following increases the amount of product from a reaction?

A)adding a metal catalyst
B)adding an acid catalyst
C)using a UV light catalyst
D)all of the above
E)none of the above

Question 24

Refer to the following graphs to answer the question(s)below.
What is the reaction profile for: N₂O₄(g)+ heat 2 NO₂(g)?

A)Graph (a)
B)Graph (b)
C)Graph (c)
D)Graph (d)
E)Graph (e)

Question 25

If the temperature of a reaction increases,which of the following is true?

A)the amount of product decreases
B)the heat of reaction increases
C)the rate of reaction increases
D)all of the above
E)none of the above

Question 26

Refer to the following graphs to answer the question(s)below.
What is the reaction profile for the following exothermic chemical reaction: H₂(g)+ F2(g) 2 HF(g)?

A)Graph (a)
B)Graph (b)
C)Graph (c)
D)Graph (d)
E)Graph (e)

Question 27

Refer to the following graphs to answer the question(s)below.
What is the reaction profile for: PCl3(g)+ Cl₂(g) PCl5(g)+ heat?

A)Graph (a)
B)Graph (b)
C)Graph (c)
D)Graph (d)
E)Graph (e)

Question 28

Which of the following is true before a reaction reaches chemical equilibrium?

A)The rates of the forward and reverse reactions are increasing.
B)The rates of the forward and reverse reactions are decreasing.
C)The rate of the forward reaction is increasing,and the rate of the reverse reaction is decreasing.
D)The rate of the forward reaction is decreasing,and the rate of the reverse reaction is increasing.
E)none of the above

Question 29

Which of the following factors influences the rate of a chemical reaction?

A)concentration
B)temperature
C)catalyst
D)all of the above
E)none of the above

Question 30

If the temperature of a reaction decreases,which of the following is true?

A)the amount of product increases
B)the heat of reaction decreases
C)the rate of reaction decreases
D)all of the above
E)none of the above

Question 31

Which of the following increases the collision frequency of molecules?

A)decreasing the concentration
B)increasing the temperature
C)adding a catalyst
D)all of the above
E)none of the above

Question 32

If the heat of reaction is endothermic,which of the following is always true?

A)the reaction rate is fast
B)the reaction rate is slow
C)the energy of the reactants is greater than the products
D)the energy of the reactants is less than the products
E)none of the above

Question 33

Refer to the following graphs to answer the question(s)below.
What is the reaction profile for the following exothermic chemical reaction: 4 HCl(g)+ O₂(g) 2 Cl₂(g)+ 2 H₂O(g)?

A)Graph (a)
B)Graph (b)
C)Graph (c)
D)Graph (d)
E)Graph (e)

Question 34

If the heat of reaction is exothermic,which of the following is always true?

A)the reaction rate is fast
B)the reaction rate is slow
C)the energy of the reactants is greater than the products
D)the energy of the reactants is less than the products
E)none of the above

Question 35

Refer to the following graphs to answer the question(s)below.
What is the reaction profile for the following endothermic chemical reaction: H₂(g)+ I₂(g) 2 HI(g)?

A)Graph (a)
B)Graph (b)
C)Graph (c)
D)Graph (d)
E)Graph (e)

Question 36

If the concentration of reactants decreases,which of the following is true?

A)the amount of product increases
B)the heat of reaction decreases
C)the rate of reaction decreases
D)all of the above
E)none of the above

Question 37

If the Eact is lowered,which of the following is always true?

A)the reaction proceeds faster
B)the reaction proceeds slower
C)the reaction is exothermic
D)the reaction is endothermic
E)none of the above

Question 38

If the concentration of reactants increases,which of the following is true?

A)the amount of product decreases
B)the heat of reaction increases
C)the rate of reaction increases
D)all of the above
E)none of the above

Question 39

Which of the following is true before a reaction reaches chemical equilibrium?

A)The amount of reactants is increasing.
B)The amount of products is increasing.
C)The amount of reactants and products are constant.
D)The amount of reactants and products are equal.
E)none of the above

Question 40

Which of the following increases the collision energy of gaseous molecules?

A)increasing the concentration
B)increasing the temperature
C)adding a catalyst
D)all of the above
E)none of the above

Question 41

What is the equilibrium constant expression for the following reaction? 2 N₂O5(g) 4 NO₂(g)+ O₂(g)

A)Keq = [N₂O5]2 / [NO₂]4 [O₂]
B)Keq = [N₂O5]2 / [NO₂]4 [O₂]2
C)Keq = [NO₂]4 [O₂] / [N₂O5]2
D)Keq = [NO₂]4 [O₂]2 / [N₂O5]2
E)none of the above

Question 42

What is the equilibrium constant expression for the following reaction? 4 HCl(g)+ O₂(g) 2 Cl₂(g)+ 2 H₂O(g)

A)Keq = [HCl] [O₂] / [Cl₂] [H₂O]
B)Keq = [HCl]4 [O₂] / [Cl₂]2 [H₂O]2
C)Keq = [Cl₂] [H₂O] / [HCl] [O₂]
D)Keq = [Cl₂]2 [H₂O]2 / [HCl]4 [O₂]
E)none of the above

Question 43

What is the equilibrium constant expression for the following reaction? CaCO₃(s) CaO(s)+ CO₂(g)

A)Keq = [CaO] [CO₂] / [CaCO₃]
B)Keq = [CaO] [CO₂]
C)Keq = [CO₂]
D)Keq = 1 / [CO₂]
E)none of the above

Question 44

What is the equilibrium constant expression for the following reaction? 2 CH₄(g)+ O₂(g) 2 CO(g)+ 4 H₂(g)

A)Keq = [CH₄] [O₂] / [CO] [H₂]
B)Keq = [CH₄]2 [O₂] / [CO]2 [H₂]4
C)Keq = [CO] [H₂] / [CH₄] [O₂]
D)Keq = [CO]2 [H₂]4 / [CH₄]2 [O₂]
E)none of the above

Question 45

What is the general equilibrium constant expression,Keq,for the following reversible reaction: 2 A B + 3 C?

A)Keq = [A] / [B] [C]
B)Keq = [A]2 / [B] [C]3
C)Keq = [B] [C] / [A]
D)Keq = [B] [C]3 / [A]2
E)none of the above

Question 46

What is the equilibrium constant expression for the following reaction? 4 NH₃(g)+ 5 O₂(g) 4 NO(g)+ 6 H₂O(g)

A)Keq = [NO] [H₂O] / [NH₃] [O₂]
B)Keq = [NO]4 [H₂O]6 / [NH₃]4 [O₂]5
C)Keq = [NH₃] [O₂] / [NO] [H₂O]
D)Keq = [NH₃]4 [O₂]5 / [NO]4 [H₂O]6
E)none of the above

Question 47

Nitrogen dioxide is produced from the reaction of nitric oxide and oxygen gases.Calculate the equilibrium constant for the reaction given the equilibrium concentrations at 25 °C: [NO] = 1.08 x 10-7,[O₂] = 0.500,and [NO₂] = 0.100. 2 NO(g)+ O₂(g) 2 NO₂(g)

A)Keq = 5.83 x 10-13
B)Keq = 1.85 x 1055
C)Keq = 1.85 x 106
D)Keq = 1.71 x 1012
E)Keq = 1.71 x 1013

Question 48

What is the general equilibrium constant expression,Keq,for the following reversible reaction: 2 A + 3 B C?

A)Keq = [A] [B] / [C]
B)Keq = [A]2 [B]3 / [C]
C)Keq = [C] / [A] [B]
D)Keq = [C] / [A]2 [B]3
E)none of the above

Question 49

What is the general equilibrium constant expression,Keq,for the following reversible reaction: A + 3 B 2 C?

A)Keq = [A] [B] / [C]
B)Keq = [A] [B]3 / [C]2
C)Keq = [C] / [A] [B]
D)Keq = [C]2 / [A] [B]3
E)none of the above

Question 50

What is the equilibrium constant expression for the following reaction? CO(g)+ 2 H₂(g) CH₃OH(l)

A)Keq = [CH₃OH] / [CO] [H₂]
B)Keq = [CH₃OH] / [CO] [H₂]2
C)Keq = [CO] [H₂]2
D)Keq = 1 / [CO] [H₂]2
E)none of the above

Question 51

What is the general equilibrium constant expression,Keq,for the following reversible reaction: A + 3 B 2 C + D?

A)Keq = [A] [B] / [C] [D]
B)Keq = [A] [B]3 / [C]2 [D]
C)Keq = [C] [D] / [A] [B]
D)Keq = [C]2 [D] / [A] [B]3
E)none of the above

Question 52

What is the equilibrium constant expression for the following reaction? SO₂(g)+ O₃(g) SO₃(g)+ O₂(g)

A)Keq = [SO₃] [O₂] / [SO₂] [O₃]
B)Keq = [SO₃]3 [O₂]2 / [SO₂]2 [O₃]3
C)Keq = [SO₂] [O₃] / [SO₃] [O₂]
D)Keq = [SO₂]2 [O₃]3 / [SO₃]3 [O₂]2
E)none of the above

Question 53

What is the equilibrium constant expression for the following reaction? C(s)+ CO₂(g) 2 CO(g)

A)Keq = [CO] / [CO₂]
B)Keq = [CO] / [C] [CO₂]
C)Keq = [CO]2 / [CO₂]
D)Keq = [CO]2 / [C] [CO₂]
E)none of the above

Question 54

A 0.500 M sample of phosgene gas,COCl₂,decomposes to give carbon monoxide and chlorine gases.If the equilibrium concentration of Cl₂ is 0.045 M,what is the equilibrium constant for the reaction? COCl₂(g) CO(g)+ Cl₂(g)

A)Keq = 0.0041
B)Keq = 0.0045
C)Keq = 0.099
D)Keq = 220
E)Keq = 250

Question 55

What is the general equilibrium constant expression,Keq,for the following reversible reaction: A + 2 B C + D?

A)Keq = [A] [B] / [C] [D]
B)Keq = [A] [B]2 / [C] [D]
C)Keq = [C] [D] / [A] [B]
D)Keq = [C] [D] / [A] [B]2
E)none of the above

Question 56

Which of the following is true after a reaction reaches chemical equilibrium?

A)The amount of reactants is increasing.
B)The amount of products is increasing.
C)The amount of reactants and products are constant.
D)The amount of reactants and products are equal.
E)none of the above

Question 57

Ultraviolet light converts oxygen to ozone in the upper atmosphere.Calculate the equilibrium constant for the reaction given the equilibrium concentrations at 20 °C: [O₂] = 9.38 x 10-3 and [O₃] = 3.40 x 10-15. 3 O₂(g) 2 O₃(g)

A)Keq = 4.11 x 10-28
B)Keq = 1.40 x 10-23
C)Keq = 3.62 x 10-13
D)Keq = 2.43 x 108
E)Keq = 7.14 x 1022

Question 58

Dinitrogen tetraoxide decomposes to produce nitrogen dioxide.Calculate the equilibrium constant for the reaction given the equilibrium concentrations at 100 °C: [N₂O₄] = 0.800 and [NO₂] = 0.400. N₂O₄(g) 2 NO₂(g)

A)Keq = 0.200
B)Keq = 0.500
C)Keq = 0.625
D)Keq = 2.00
E)Keq = 5.00

Question 59

What is the equilibrium constant expression for the following reaction? 2 CO(g)+ O₂(g) 2 CO₂(g)

A)Keq = [CO₂]2 / [CO]2 [O₂]
B)Keq = [CO₂]2 / [CO]2 [O₂]2
C)Keq = [CO]2 [O₂] / [CO₂]2
D)Keq = [CO]2 [O₂]2 / [CO₂]2
E)none of the above

Question 60

What is the general equilibrium constant expression,Keq,for the following reversible reaction: 2 A + 3 B 4 C + D?

A)Keq = [A] [B] / [C] [D]
B)Keq = [A]2 [B]3 / [C]4 [D]
C)Keq = [C] [D] / [A] [B]
D)Keq = [C]4 [D] / [A]2 [B]3
E)none of the above

Question 61

Which of the changes listed will shift the equilibrium to the left for the following reversible reaction? 2 NO(g)+ 2 CO(g) N₂(g)+ 2 CO₂(g)+ heat

A)increase [CO]
B)decrease [CO₂]
C)increase temperature
D)decrease volume
E)add krypton gas

Question 62

Which of the changes listed will shift the equilibrium to the right for the following reversible reaction? SO₃(g)+ NO(g)+ heat SO₂(g)+ NO₂(g)

A)increase [SO₃]
B)increase [SO₂]
C)decrease temperature
D)increase volume
E)add a catalyst

Question 63

Which of the changes listed has no effect on the equilibrium for the following reversible reaction? 2 NO(g)+ 2 CO(g) N₂(g)+ 2 CO₂(g)+ heat

A)increase [NO]
B)increase [CO₂]
C)increase temperature
D)increase volume
E)add a catalyst

Question 64

Which of the changes listed will shift the equilibrium to the left for the following reversible reaction? SO₃(g)+ NO(g)+ heat SO₂(g)+ NO₂(g)

A)increase [NO]
B)decrease [SO₂]
C)decrease temperature
D)decrease volume
E)add a catalyst

Question 65

A 4.750 M sample of hydrogen iodide decomposes to give hydrogen and iodine gases.If the equilibrium concentration of H₂ is 0.500 M,what is the equilibrium constant for the reaction? 2 HI(g) H₂(g)+ I₂(g)

A)Keq = 0.0111
B)Keq = 0.0138
C)Keq = 0.0178
D)Keq = 0.0588
E)Keq = 0.0667

Question 66

Which of the changes listed will shift the equilibrium to the right for the following reversible reaction? 2 NO(g)+ 2 CO(g) N₂(g)+ 2 CO₂(g)+ heat

A)decrease [NO]
B)increase [N₂]
C)increase temperature
D)decrease volume
E)add a catalyst

Question 67

Which of the changes listed has no effect on the equilibrium for the following reversible reaction? CO(g)+ H₂O(g) CO₂(g)+ H₂(g)+ heat

A)increase volume
B)decrease volume
C)add a catalyst
D)add neon gas
E)all of the above

Question 68

What is the equilibrium constant expression,Ki,for the following weak acid? H₂CO₃(aq) H+(aq)+ HCO₃-(aq)

A)Ki = [H+] [HCO₃-] / [H₂CO₃]
B)Ki = [H+]2 [HCO₃-] / [H₂CO₃]
C)Ki = [H+]2 [CO₃2-] / [H₂CO₃]
D)Ki = [H₂CO₃] / [H+] [HCO₃-]
E)Ki = [H₂CO₃] / [H+]2 [CO₃2-]

Question 69

What is the equilibrium constant expression,Ki,for the following weak acid? H₃PO₄(aq) H+(aq)+ H₂PO₄-(aq)

A)Ki = [H+] [H₂PO₄-] / [H₃PO₄]
B)Ki = [H+]3 [H₂PO₄-] / [H₃PO₄]
C)Ki = [H+]3 [PO₄3-] / [H₃PO₄]
D)Ki = [H₃PO₄] / [H+] [H₂PO₄-]
E)Ki = [H₃PO₄] / [H+]3 [PO₄3-]

Question 70

What is the equilibrium constant expression,Ki,for the following weak base? NH₂OH(aq)+ H₂O(l) NH₃OH+(aq)+ OH-(aq)

A)Ki = [NH₃OH+] [OH-] / [NH₂OH]
B)Ki = [NH₃OH+] [OH-] / [NH₂OH] [H₂O]
C)Ki = [NH₃OH+] [OH-]
D)Ki = [NH₂OH] / [NH₃OH+] [OH-]
E)Ki = [NH₂OH] [H₂O] / [NH₃OH+] [OH-]

Question 71

A 0.750 M sample of phosphorus pentachloride decomposes to give phosphorus trichloride and chlorine gases.If the equilibrium concentration of PCl5 is 0.650M,what is the equilibrium constant for the reaction? PCl5(g) PCl3(g)+ Cl₂(g)

A)Keq = 0.0133
B)Keq = 0.0154
C)Keq = 0.133
D)Keq = 0.154
E)Keq = 65.0

Question 72

Which of the changes listed will shift the equilibrium to the right for the following reversible reaction? CO(g)+ H₂O(g) CO₂(g)+ H₂(g)+ heat

A)increase [CO]
B)increase [CO₂]
C)increase temperature
D)increase volume
E)add a catalyst

Question 73

Which of the changes listed will shift the equilibrium to the left for the following reversible reaction? CH₄(g)+ H₂O(g)+ heat CO(g)+ 3 H₂(g)

A)increase [H₂O]
B)decrease [H₂]
C)decrease temperature
D)increase volume
E)none of the above

Question 74

Which of the changes listed has no effect on the equilibrium for the following reversible reaction? SO₃(g)+ NO(g)+ heat SO₂(g)+ NO₂(g)

A)increase volume
B)decrease volume
C)add a catalyst
D)add helium gas
E)all of the above

Question 75

What is the equilibrium constant expression,Ki,for the following weak acid? H₂SO₃(aq) H+(aq)+ HSO₃-(aq)

A)Ki = [H+] [HSO₃-] / [H₂SO₃]
B)Ki = [H+]2 [HSO₃-] / [H₂SO₃]
C)Ki = [H+]2 [SO₃2-] / [H₂SO₃]
D)Ki = [H₂SO₃] / [H+] [HSO₃-]
E)Ki = [H₂SO₃] / [H+]2 [SO₃2-]

Question 76

Which of the changes listed will shift the equilibrium to the right for the following reversible reaction? CH₄(g)+ H₂O(g)+ heat CO(g)+ 3 H₂(g)

A)increase [CH₄]
B)decrease [CO]
C)increase temperature
D)increase volume
E)all of the above

Question 77

Which of the changes listed will shift the equilibrium to the left for the following reversible reaction? CO(g)+ H₂O(g) CO₂(g)+ H₂(g)+ heat

A)increase [H₂O]
B)decrease [CO₂]
C)increase temperature
D)decrease volume
E)add a catalyst

Question 78

What is the equilibrium constant expression,Ki,for the following weak acid? H₂S(aq) H+(aq)+ HS-(aq)

A)Ki = [H+] [HS-] / [H₂S]
B)Ki = [H+]2 [HS-] / [H₂S]
C)Ki = [H+]2 [S₂-] / [H₂S]
D)Ki = [H₂S] / [H+] [HS-]
E)Ki = [H₂S] / [H+]2 [HS-]

Question 79

What is the equilibrium constant expression,Ki,for the following weak base? NH₄OH(aq) NH₄+(aq)+ OH-(aq)

A)Ki = [NH₄+] [OH-] / [NH₄OH]
B)Ki = [NH₄+]4 [OH-] / [NH₄OH]
C)Ki = [NH₄+]4 [OH-]
D)Ki = [NH₄OH] / [NH₄+] [OH-]
E)Ki = [NH₄OH] / [NH₄+]4 [OH-]

Question 80

Which of the changes listed has no effect on the equilibrium for the following reversible reaction? CH₄(g)+ H₂O(g)+ heat CO(g)+ 3 H₂(g)

A)increase [H₂O]
B)decrease [H₂]
C)decrease temperature
D)increase volume
E)add argon gas