Deck 13: Chemical Equilibrium

Question 1

What produces energy in the cells of the body?

A)The cell nucleus
B)The mitochondria
C)Aerobic respirators
D)The electrolytes

Answer 1

B

Question 2

When does the body utilize anaerobic respiration?

A)Only when electrolytes are present
B)At all times
C)When sufficient oxygen is supplied to cells during exercise or activity
D)When energy expenditure outpaces the supply of oxygen

Answer 2

D

Question 3

What is the name of a chemical substance that can be dangerous in low amounts?

A)A pathogen
B)A herbicide
C)A toxic compound
D)An insecticide

Answer 3

C

Question 4

What are the entry routes to the body for a poison?

A)Ingestion
B)Physical contact
C)Inhalation
D)All of the above

Question 5

How are most poisons transported through the body?

A)Via the kidneys
B)By the respiratory system
C)Through the lymph nodes
D)By the circulatory system

Question 6

What is one of the main proteins found in blood plasma, to which poisons can bind?

A)Hemoglobin
B)Albumin
C)Retinal
D)None of the above

Question 7

What is a chemical equilibrium?

A)A balance of two competing reactions
B)One reaction running to completion, followed by its reverse reaction
C)One reaction being countered by its reverse reaction
D)Two unrelated reactions running at the same time

Question 8

What is the symbol for an equilibrium reaction?

A)=
B)←
C)→
D)⇌

Question 9

What controls both the forward and reverse reactions of an equilibrium?

A)Activation energy barrier
B)Restrictions of collision theory
C)Both of the above
D)None of the above

Question 10

How does the energy of activation restrict an equilibrium reaction?

A)It limits the molecules that will have enough energy to react.
B)It cools the reaction by draining it of energy.
C)It blocks the forward reaction with the formation of products.
D)It slows both forward and reverse reactions.

Question 11

Water cannot be a toxin, even if it is ingested in extremely large amounts.

Question 12

Why are poisons always an organic or inorganic compound?

A)Because these compounds have optimal interaction with cells
B)Because such compounds are the correct size for cellular interactions
C)Because such compounds have the correct polarity to interact with proteins
D)They aren't; pure elements can be poisons too.

Question 13

What does LD₅₀ stand for?

A)Life division 50
B)Lethal dosage for 50% of a population
C)Life diminisher, 50%
D)Living divisor, 50%

Question 14

LD₅₀s for most toxins are at or above 1500 mg/kg.

Question 15

Why do common compounds, such as sodium chloride, not have an LD₅₀?

A)Because they are not poisons
B)Because such materials are food products
C)Because it has not yet been determined
D)None of the above; all compounds, even materials such as sodium chloride, do have an LD₅₀.

Question 16

An LD₅₀ is determined for what type of poisoning?

A)Corrosive
B)Multiple exposure
C)Acute
D)Chronic

Question 17

What is a teratogen?

A)A poison that causes cancer
B)A poison that induces birth defects
C)A chronic poison
D)An acute poison

Question 18

What occurs in a dynamic equilibrium, even though there is no apparent change in the system?

A)The forward reaction continues
B)The reverse reaction continues
C)Both of the above
D)None of the above

Question 19

Over time, what do the concentrations of reactants and products become in a dynamic equilibrium?

A)Equal
B)Constant
C)Zero
D)Infinite

Question 20

How does the presence of a catalyst affect an equilibrium system?

A)It lowers the activation energy of the forward reaction.
B)It lowers the activation energy for both reactions.
C)It lowers the activation energy of the reverse reaction.
D)It has no effect.

Question 21

A catalyst added to a system going to equilibrium does what?

A)Raises the activation energy of the reverse reaction
B)Lowers the activation energy for the forward reaction
C)Increases each reaction's rate, allowing equilibrium to be reached faster
D)Nothing

Question 22

What is K the symbol for in an equilibrium?

A)The equilibrium constant
B)The product concentration
C)The reactant concentration
D)The equilibrium percentage

Question 23

How is K expressed in terms of reactants and products?

A)[reactants]^r / [products]^p
B)[products]^p / [reactants]^r
C)[products]^p × [reactants]^r
D)[reactants]^r × [products]^p

Question 24

Under what condition is the K for a chemical reaction always constant?

A)Constant temperature
B)Constant pressure
C)Constant volume
D)None of the above

Question 25

When the value of K is very large (e.g., greater than 1000), how does the equilibrium exist?

A)As a dynamic equilibrium
B)As a relatively even mixture of products and reactants
C)As mostly reactants
D)As mostly products

Question 26

What is the equilibrium expression for the reaction HA ⇌ H⁺ + A^- ?

A)K = [HA] / [H⁺][A^-]
B)K = [H^-][A⁺] / [HA]
C)K = [HA] / [H^-][A⁺]
D)K = [H⁺][A^-] / [HA]

Question 27

What is another name for the equilibrium constant?

A)The stability constant
B)The association constant
C)The binding constant
D)All of the above

Question 28

What does a value of 1.50 × 10⁴ for an equilibrium constant indicate about the reaction?

A)The equilibrium lies far to the reactants side.
B)The equilibrium is roughly equal amounts of products and reactants.
C)The equilibrium lies far to the products side.
D)The number does not indicate anything about the equilibrium.

Question 29

In the reaction HA ⇌ H⁺ + A^-, what is the value of K if [HA] = 0.200 M and [A^-] = [H⁺] = 0.020 M?

A)0.0004
B)0.200
C)0.010
D)0.002

Question 30

What is the value of K in the reaction HA ⇌ H⁺ + A^- if [HA] = 0.001 M and [A^-] = [H⁺] = 0.020 M?

A)0.0004
B)4.0 × 10^-7
C)0.200
D)0.400

Question 31

In the reaction HCl ⇌ H⁺ + Cl^- , what is the value of K if [HCl] = 0.001 M and [Cl^-] = [H⁺] = 0.20 M?

A)0.04
B)40.0
C)0.20
D)None of the above

Question 32

In the reaction HA ⇌ H⁺ + A^- , how can the K value be an extremely high number?

A)The reactants can be vanishingly small.
B)Each product can be small.
C)The reactant can be large, while one product is large.
D)The products can be vanishingly small.

Question 33

In an equilibrium whose reaction is expressed HAc ⇌ H⁺ + Ac^- , how can K equal a number greater than 1000 if the product concentrations are never greater than 0.2 M each?

A)The product concentrations must be halved.
B)The reactant concentration must be as small as 4.0 × 10^-5.
C)The reactant concentrations must be made as large as 5.0 × 10⁵.
D)The product concentrations must be very close to zero.

Question 34

What is the reactant concentration, [HA], in a reaction such as HA ⇌ H⁺ + A^- , when K = 0.21 and [H⁺] = 0.13 M?

A)0.080 M
B)0.020 M
C)0.130 M
D)0.003 M

Question 35

What is [HA] in the reaction HA ⇌ H⁺ + A^- , when [H⁺] = 0.23 M and K = 1.8?

A)0.128 M
B)0.053 M
C)0.029 M
D)0.100 M

Question 36

In the reaction HCl ⇌ H⁺ + Cl^- , when K = 2.1 and [H⁺] = 0.33 M, what is [HCl]?

A)0.229 M
B)0.693 M
C)0.052 M
D)0.109 M

Question 37

What is the reactant concentration, [HA], in a reaction such as HA ⇌ H⁺ + A^- , when the K = 0.10 and [H⁺] = 0.001 M?

A)1 × 10^-5
B)1 × 10^-6
C)1 × 10^-3
D)1 × 10^-2

Question 38

What is [HA] in the reaction HAc ⇌ H⁺ + Ac^-, when K = 0.83 and [H⁺] = 0.15 M?

A)0.019 M
B)0.180 M
C)0.023 M
D)0.027 M

Question 39

What is the reactant concentration, [HA], in HA ⇌ H⁺ + A^- , when [H⁺] = 0.010 M and K = 2.05?

A)1.00 × 10^-4
B)4.87 × 10^-5
C)4.87 × 10^-3
D)1.00 × 10^-3

Question 40

What is the K of the reaction HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^- , if [HC₂H₃O₂] = 0.15 M and the pH = 3.0?

A)1.00 × 10^-6
B)6.67 × 10^-6
C)3.34 × 10^-6
D)1.50 × 10^-7

Question 41

In the following reaction: HA ⇌ H⁺ + A^- , what is K if [HA] = 0.25 M and the pH for the solution is 2.00?

A)0.0002
B)0.0004
C)0.0001
D)7.00

Question 42

What is K for the following reaction: HBr ⇌ H⁺ + Br^- , if [HBr] = 0.50 M and the pH = 2.0?

A)0.0002
B)0.0001
C)0.0010
D)0.0020

Question 43

For the following reaction: HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^- , if [HC₂H₃O₂] = 1.0 × 10^-8 M and the pH = 3.0, what is K?

A)1.0 × 10^-2
B)10.0
C)1.00 × 10^-6
D)100

Question 44

In the reaction HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^- , if [HC₂H₃O₂] = 1.0 × 10^-6 M and the pH = 4.0, what will K be?

A)1.0 × 10^-8
B)0.10
C)0.01
D)1.0 × 10^-4

Question 45

To find K for the following reaction: HA ⇌ H⁺ + A^- , what value is required besides pH?

A)[HA]
B)[A^-]
C)[H⁺]
D)Nothing more is required.

Question 46

What is the K of the following reaction: HI ⇌ H⁺ + I^- , if [HI] = 0.15 M and the pH = 1.0?

A)0.10
B)0.07
C)0.06
D)0.01

Question 47

What is the K of the following reaction: HA ⇌ H⁺ + A^- , if [HA] = 0.10 M and the pH = 1.0?

A)1.0
B)0.1
C)0.01
D)0.5

Question 48

In the following reaction: HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^-, if [HC₂H₃O₂] = 0.28 M and the pH = 5.0, what is K?

A)3.57 × 10^-10
B)1.00 × 10^-4
C)1.00 × 10^-10
D)3.57 × 10^-4

Question 49

What is the [H⁺] in the following reaction: HA ⇌ H⁺ + A^- , if [HA] = 0.150 M and K = 0.02?

A)0.030 M
B)0.054 M
C)0.150 M
D)0.020 M

Question 50

In the following reaction: HAc ⇌ H⁺ + Ac^- , if [HAc] = 0.250 M, and K = 0.35, what is [H⁺]?

A)1.18 M
B)1.40 M
C)0.086 M
D)0.295 M

Question 51

In the following reaction: HBr ⇌ H⁺ + Br^- , what is [H⁺] equal to, given that [HBr] = 0.100 M and K = 23.1?

A)231 M
B)2.31 M
C)1.52 M
D)15.2 M

Question 52

What is the [H⁺] in the following reaction: HA ⇌ H⁺ + A^- , when [HA] = 0.050 M and K = 0.28?

A)0.118 M
B)0.014 M
C)5.60 M
D)2.36 M

Question 53

What is [H⁺] in the following reaction: HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^- , when [HC₂H₃O₂] = 0.130 M and K = 0.11?

A)0.0143 M
B)0.85 M
C)0.12 M
D)0.92 M

Question 54

In the following reaction: HCl ⇌ H⁺ + Cl^- , what is the pH value if [HCl] = 0.200 M and K = 1 × 10^-9?

A)2.00
B)1.50
C)4.85
D)Can't tell from the information provided.

Question 55

In the following reaction: HA ⇌ H⁺ + A^- , what is the pH value if [HA] = 0.300 M and K = 1 × 10^-5?

A)8.24
B)0.30
C)5.52
D)2.76

Question 56

In the following reaction: HBr ⇌ H⁺ + Br^- , what is the pH value if [HBr] = 0.120 M and K = 1 × 10^-8?

A)3.46
B)4.46
C)0.45
D)1.20

Question 57

What is the pH in the following reaction: HI ⇌ H⁺ + I^- , if the [HI] = 0.250 M and K = 1 × 10^-6?

A)3.30
B)5.00
C)2.50
D)0.25

Question 58

In the following reaction: HA ⇌ H⁺ + A^- , what will the pH value be if [HA] = 0.150 M and K = 5.2 × 10^-9?

A)2.79
B)4.55
C)7.80
D)5.20

Question 59

In the equilibrium reaction HAc ⇌ H⁺ + Ac^-, what is the pH of the solution if [HAc] = 0.420 M and K = 4.8 × 10^-8?

A)1.42
B)2.02
C)3.85
D)4.80

Question 60

What is the value of K in the following: HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^-?

A)0.04
B)0.10
C)0.02
D)Not enough information to tell

Question 61

What value in an equilibrium reaction does K have if the other values for the reaction HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^- are [A^-] = 0.10 M and [HC₂H₃O₂] = 0.25 M?

A)0.01
B)0.04
C)0.03
D)0.25

Question 62

What is the value of K in the equilibrium reaction HA ⇌ H⁺ + A^- if [H⁺] = 0.020 M and [HA] = 0.200 M?

A)0.0200
B)0.0008
C)0.0020
D)0.0004

Question 63

What is the value of K in the equilibrium reaction of acetic acid: HC₂H₃O₂ ⇌ H⁺ + C₂H₃O₂^-, if [H⁺] = 0.20 M and [HC₂H₃O₂] = 0.30 M?

A)0.13
B)0.04
C)0.20
D)0.012

Question 64

What is the value of [HAc] in the reaction HAc ⇌ H⁺ + Ac^- , if the K = 47.0 and the [H] = 0.350 M?

A)5.76 M
B)0.123 M
C)0.003 M
D)47.0 M

Question 65

An equilibrium reaction of the formula HA ⇌ H⁺ + A^- has an equilibrium constant of 13.5 and a [H⁺] = 0.500 M. What is the value of [HA]?

A)13.5 M
B)54.0 M
C)0.250 M
D)0.018 M

Question 66

When an equilibrium is established, what is the relationship between the products and the reactants?

A)There is a greater concentration of products than reactants.
B)There is a greater concentration of reactants than products.
C)The products and reactants are equal.
D)All of the above are possibilities.

Question 67

Starting with only reactants, what happens to the concentration of reactants prior to establishing an equilibrium?

A)They decrease.
B)They increase.
C)They essentially stay the same.
D)Both a and c are correct.

Question 68

What is the main protein in blood plasma, which invariably a toxin will encounter?

A)Hemoglobin
B)Metal-albumin
C)Albumin
D)None of the above

Question 69

The equilibrium constant, K, is a measure of product concentration terms divided by reactant concentration terms.

Question 70

The equilibrium HA ⇌ H⁺ + A^- shows complete dissociation in any equilibrium.

Question 71

Why does a small equilibrium constant indicate an equilibrium that lies mostly on the products side of a reaction?

A)Because the product concentrations are high
B)Because the reactant concentrations are low
C)Because the value of the products divided by the reactants is high
D)It doesn't; rather, it indicates an equilibrium that lies mostly on the reactants side of the equation.

Question 72

What is the difference between an equilibrium constant and a binding constant?

A)The binding constant is actually determined using the equilibrium constant for a specific reaction.
B)Equilibrium constants are always determined by the concentration of reactants.
C)Binding constants are always determined from the formation of products.
D)Nothing; they are the same.

Question 73

What does it mean when the value of an equilibrium constant for a reaction is at or close to 1?

A)The value of the product concentration term divided by the reactant concentration term is at or close to 1.
B)The value of the product concentration term must be at or close to 1.
C)The value of the reactant concentration term or the product concentration term must be at or close to 1.
D)The value of the product concentration term divided by the reactant concentration term is at or close to 1 because the value of each concentration term is at or close to 1.

Question 74

When oxygen gas is removed from hemoglobin, and this equilibrium is disturbed, what is the result?

A)Other gases replace the oxygen that was removed.
B)Nothing, the new equilibrium is established.
C)Less oxygen is used to replace what was removed.
D)More oxygen is produced to replace what was removed.

Question 75

How does carbon monoxide bind to hemoglobin?

A)With the same strength as oxygen gas
B)More strongly than oxygen
C)Less strongly than oxygen gas
D)The binding varies from person to person

Question 76

What happens to the oxygen/hemoglobin equilibrium when a person is exposed to CO?

A)Nothing.
B)It becomes the CO/hemoglobin equilibrium.
C)It is disturbed.
D)It becomes the oxygen/CO equilibrium.

Question 77

What happens to the hemoglobin's ability to transport oxygen (O₂) when carbon monoxide (CO) is bound to it?

A)It decreases.
B)It increases.
C)It remains the same.
D)It varies from person to person.

Question 78

During or immediately after carbon monoxide poisoning, what should be done to shift the equilibrium to the production of oxyhemoglobin?

A)Expose the affected person to oxygen.
B)Limit the affected person's exposure to oxygen.
C)Expose the affected person to a progressively decreasing CO/O₂ mixture.
D)Expose the affected person to a low-pressure atmosphere.

Question 79

What does a hyperbaric oxygen chamber do?

A)Provide a clean source of oxygen and nitrogen to bind with carbon monoxide
B)Increase the volume of the affected person's lung tissue
C)Decreases the temperature of the person, and hence their lungs
D)Increases the oxygen pressure to a CO-poisoned person

Question 80

What waste product does hemoglobin transport?

A)Urea
B)Carbon dioxide
C)Carbon monoxide
D)Carbonate