Deck 11: Applications of Chemical Kinetics

Question 1

What is the goal of green chemistry in the drug industry?

A)Prevention of pollution
B)The reduction of waste by-products
C)The use of less energy during drug production
D)Both b and c

Answer 1

D

Question 2

What is a common problem associated with drug production?

A)Low yields of desired products at different synthetic steps
B)Production of unwanted by-products
C)The production of large amounts of unwanted chemical waste
D)All of the above

Answer 2

D

Question 3

What is the purpose of the drug atorvastatin?

A)It lowers blood pressure.
B)It corrects erectile dysfunction.
C)It lowers drug serum cholesterol.
D)It is a by-product of Lipitor production.

Answer 3

C

Question 4

During drug synthesis, how much of a desired compound is produced during a synthetic reaction?

A)5-10%
B)30-50%
C)At least 75%
D)Well over 75%

Question 5

Within chemistry, what is the study of chemical kinetics?

A)The temperature of chemical reactions
B)The concentrations of chemical reactants and products
C)The rate of chemical reactions
D)All of the above

Question 6

How is reaction rate determined?

A)By decrease of reactants with time
B)By increase of products with time
C)Both of the above
D)None of the above

Question 7

In the following reaction, 4 Na + O₂ → 2 Na₂O, how can the rate of the reaction be determined?

A)By the 4-to-1 ratio of the reactants
B)By the increase of O₂ with time
C)By the increase of Na with time
D)By the formation of Na₂O over time

Question 8

In the decomposition reaction in which CaCO₃ breaks down to form CaO and CO₂, how can the rate of reaction be measured?

A)By the heat of the reaction
B)By the formation of CO₂ over time
C)By the number of moles of product
D)By the formation of CaCO₃ over time

Question 9

How can the rate of the reaction H₂ + Cl₂ → 2 HCl be measured?

A)By the loss of H₂ over time
B)By how much Cl₂ is used overall
C)By how much HCl is formed
D)By monitoring the reaction temperature

Question 10

In the reaction 2 H₂ + O₂ → 2 H₂O, what is the rate of loss of H₂ when compared to the rate of H₂O formation?

A)You cannot tell from the reaction.
B)H₂ loss is greater.
C)H₂O formation is greater.
D)They are the same.

Question 11

How does the rate of iron loss compare to the rate of iron(III) oxide formation in the equation 4 Fe + 3 O₂ → 2 Fe₂O₃?

A)They are the same.
B)The iron(III) oxide rate is greater.
C)It is twice as great.
D)It is twice as small.

Question 12

According to the balanced chemical equation HCl + NaOH → H₂O + NaCl, what is the rate of HCl loss compared to that of NaCl formation?

A)They are the same.
B)HCl loss is greater.
C)NaCl formation is greater.
D)Cannot tell from the reaction.

Question 13

If coal has more energy per gram than nitroglycerin, why isn't its combustion considered an explosion?

A)Its lower explosion level (LEL) is too low for it to be considered a true explosion.
B)It requires too high an ignition temperature.
C)The rate is too slow.
D)The concentration is never high enough for an explosion.

Question 14

The decrease in the concentration of products is a routine way to measure the rate of a chemical reaction.

Question 15

When nitrogen gas is combined with oxygen gas to form nitrogen monoxide, according to the reaction N₂ + O₂ → 2NO, what can be used to measure the rate of the reaction?

A)NO formation
B)N₂ consumption
C)O₂ production
D)Both a and b

Question 16

Why are reactions in the liquid state usually slower than those in the solid state?

A)Because they have less surface area upon which the reaction can occur
B)Because the particles possess less kinetic energy in the liquid state
C)Because powders and other solids have numerous reaction sites
D)None of the above. Reactions in the solid state are generally slower.

Question 17

What can prevent a reaction from occurring, on the molecular level, even if both particles have sufficient kinetic energy to react?

A)The size of each particle
B)The solvent in which the particles exist
C)The orientation of each particle
D)Nothing; they will react.

Question 18

Collision theory is a model of how chemical reactions occur on a cellular level.

Question 19

According to collision theory, what must the molecules of reactants do in order for a reaction to occur?

A)Collide
B)Heat up
C)Be pressurized
D)Expand

Question 20

What type of molecular-level collisions result in products?

A)Low-energy, directed collisions
B)High-energy collisions
C)High-energy, high-temperature collisions
D)None of the above

Question 21

Why doesn't a product form when particles collide, according to collision theory?

A)The particles may have too high an energy.
B)The particles may not be of high enough energy.
C)The particles may not be the right size.
D)The particles may not collide.

Question 22

Why do less reactant particles form products in many reactions as time goes on?

A)There is less energy for the particles to react.
B)There are smaller areas in which particles can react.
C)Most particles have already formed products.
D)None of the above.

Question 23

How will the reaction of 0.5 M HCl and 0.5 M KOH proceed when compared to the same reaction utilizing 0.2 M solutions?

A)The initial rate of reaction should be faster.
B)The initial rate of the reaction should be slower.
C)The final reaction rate should be faster.
D)There should be no difference.

Question 24

How will the reaction 2 AgNO₃ + Cu → Cu(NO₃)₂ + 2 Ag proceed with an AgNO₃ concentration of 0.30 M, as opposed to a 0.10 M solution?

A)Slower at first
B)Faster at first
C)Faster when pressurized
D)Slower throughout

Question 25

When can the increased speed of a reaction be a problem?

A)When an explosion occurs
B)When the reactants stop mixing
C)When products do not form
D)When the reaction is cooled

Question 26

When two aqueous salt solutions are mixed, how will they react if higher concentrations of each are mixed, versus lower concentrations?

A)The concentration does not matter for reaction rate.
B)Lower concentrations will react more swiftly at the outset.
C)Higher concentrations will yield more products.
D)Higher concentrations will react more swiftly at the outset.

Question 27

According to collision theory, why must particles have a high energy?

A)To enhance the energy of the system
B)To increase the probability of particle motion
C)To orient correctly
D)To collide effectively

Question 28

When reactions are heated, they usually speed up.

Question 29

What about an insect is dependent upon temperature?

A)Its activity level
B)Its growth rate
C)Both of the above
D)None of the above

Question 30

Why are the largest and smallest larvae found in a body at a crime scene collected and preserved?

A)They allow the pathologist to know the exact time of death.
B)They can tell the temperature of the body at the crime scene.
C)They represent the thinnest and fattest, and give a window into how long the body has been present.
D)They represent the oldest and youngest, and give a window into how long the body has been present.

Question 31

If an insect species requires 18 hours at 28°C to develop from egg to larva, how many accumulated degree hours is this?

A)540 ADH
B)10 ADH
C)46 ADH
D)504 ADH

Question 32

If an insect species needs 486 accumulated degree hours (ADH) to develop from egg to larva, how many hours will it take to develop at 27°C?

A)12
B)18
C)24
D)30

Question 33

If an insect species needs 520 ADH to develop from egg to larva at 26°C, how many hours will it take to develop?

A)20
B)18
C)16
D)14

Question 34

How many ADH are required for an insect to go from egg to larva if it normally does so in 16 hours at 30°C?

A)540
B)480
C)620
D)500

Question 35

Why do most reactions increase in rate as the temperature rises?

A)The increased kinetic energy enables more successful collisions.
B)The decreased kinetic energy enables more successful collisions.
C)The increased kinetic energy enables fewer successful collisions.
D)The decreased kinetic energy enables fewer successful collisions.

Question 36

What is the activation energy barrier?

A)The energy required to prevent a reaction from occurring
B)The energy needed to stop a particle collision
C)The energy required for a successful reactant particle collision
D)The energy needed to initiate particle movement

Question 37

What happens to the fraction of molecules able to collide successfully in a system when the system is cooled?

A)The fraction is not affected.
B)The fraction increases.
C)The fraction decreases.
D)There is not enough information to tell.

Question 38

Why do insects grow more slowly in cooler temperatures?

A)The cells are not large enough at lowered temperature.
B)Because they are warm-blooded, but unable to move from the larval state at lower temperatures.
C)The biochemical reactions that govern their growth occur more slowly at lower temperatures.
D)None of the above; they actually grow faster at slightly cooled temperatures.

Question 39

What do ADH incorporate into their values?

A)Volume and temperature
B)Time and temperature
C)Time and potential energy
D)None of the above

Question 40

Pure substances are used to compute higher ADH than impure mixtures of substances.

Question 41

Why is the total amount of heat needed to get to a specific insect growth stage different at high versus low temperatures?

A)There is a greater kinetic energy in the higher temperature system.
B)There are more cells involved at the higher temperatures.
C)Because the larva requires the higher heat to reach the adult stage.
D)It isn't. The specific heat is the same, even though the growth rates are different.

Question 42

If the ADH for a species development is 400, how much would the temperature have to be changed to cut the growth time by a factor of two?

A)It doesn't need to be changed at all.
B)It should be doubled.
C)It should be quadrupled.
D)It should be halved.

Question 43

If the ADH of an insect species' development is 200, and the species usually required 8 hours to develop, how can the development time be cut to 1 hour?

A)Increase the temperature from 25°C to 200°C.
B)Increase the temperature to 100°C and immerse the larvae in a microwave environment.
C)Utilize eight times the amount of larval samples as the development begins.
D)It can't; the required temperature is simply too high.

Question 44

What does a catalyst provide for two reactants, on a molecular level?

A)An accelerant
B)A biphase at which the two materials can align
C)An alternate pathway and site for the reactants to meet and form products
D)None of the above, as catalysts do nothing at the molecular level

Question 45

What do all homogeneous catalysts have in common?

A)A metal center
B)Aqueous solubility
C)Solubility in organic solvents
D)They are in the same phase as the reactants.

Question 46

Why aren't exothermic reactions catalyzed?

A)Because the reaction gives off energy
B)Because the reaction requires minimal or no energy input
C)Because they occur so quickly
D)None of the above; they can be catalyzed if necessary.

Question 47

Heterogeneous catalysts have the distinct advantage of being easier to mix with reactants than homogeneous solutions.

Question 48

What defines a catalyst?

A)A material that speeds up a reaction rate
B)A material that is used up in a reaction
C)A material that is not used up in a reaction
D)Both a and c are correct.

Question 49

What chemical releases energy as blue-green light when oxidized by a reaction with hydrogen peroxide?

A)Laminal
B)Luminescence
C)Laminescence
D)Luminol

Question 50

What in blood increases the reaction rate of luminal and hydrogen peroxide?

A)Hemoglobin
B)Iron
C)Globin
D)Heme

Question 51

What do catalysts always do?

A)Increase a reaction yield
B)Speed up a reaction
C)Get consumed in the reaction
D)Lower the energy of the reactants

Question 52

How do catalysts function in a reaction?

A)By speeding up the collisions of particles
B)By lowering the activation energy of the reaction
C)By combining with the products
D)None of the above

Question 53

What are the two classes of catalysts?

A)Heterogeneous and homogeneous
B)Heterogeneous and chemiluminescent
C)Homogeneous and chemiluminescent
D)None of the above

Question 54

What is the catalyst for hydrogen peroxide's (H₂O₂) decomposition when it is placed in a wound?

A)Foreign objects in the tissue of the wound
B)Bacteria in the wound
C)Scar tissue
D)Blood

Question 55

What kind of catalyst is always in the same physical state as the reactant?

A)Heterogeneous catalyst
B)Iron catalyst
C)Homogeneous catalyst
D)Chemiluminescent catalyst

Question 56

What is a reaction intermediate?

A)A compound formed in the first step of a reaction but that is immediately consumed.
B)A compound formed in the midst of a reaction that is not consumed.
C)A compound formed in the first step of a reaction that is not consumed.
D)A compound formed in the midst of a reaction but that is immediately consumed.

Question 57

In the energy diagram for an endothermic reaction, what will be the only difference between the catalyzed and uncatalyzed plot of the reaction?

A)The product's energy will be higher for the uncatalyzed plot.
B)The energy of activation will be higher for the uncatalyzed plot.
C)The energy of activation will be lower for the uncatalyzed plot.
D)The product's energy will be lower for the uncatalyzed plot.

Question 58

In a heterogeneously catalyzed reaction, what must the reactants do to a solid catalyst?

A)React with it
B)Adhere to it for a short period of time
C)Adhere to it for a prolonged or permanent time
D)Fail to react with it

Question 59

Why is enhanced surface area important in heterogeneous catalysis?

A)Because it provides the maximum number of catalytic sites
B)Because it provides the minimum number of catalytic sites
C)Because it activates the catalytic sites
D)Because it deactivates the catalytic sites

Question 60

How is the presence of a catalyst represented in an energy level diagram?

A)By the letter "C" at the transition state site
B)By a lowered energy of activation
C)By a heightened reactant initial energy
D)By a lowered product final energy

Question 61

A catalyst lowers the activation energy barrier, which is the maximum amount of energy required during a collision.

Question 62

What is the advantage of a homogeneous catalyst versus a heterogeneous catalyst in a reaction?

A)Homogeneous catalysts are easier to identify with spectroscopy during the reaction.
B)A homogeneous catalyst is easier to separate from products.
C)Every particle of a homogeneous catalyst is able to react.
D)Homogeneous catalysts are less expensive.

Question 63

How do homogeneous catalysts mix with reactant solutions?

A)Thoroughly.
B)Swiftly, but only when heated.
C)They mix if enough kinetic energy is added.
D)They do not mix.

Question 64

How are heterogeneous catalysts separated from a reaction's products?

A)Chromatographically
B)Distillation
C)Filtration
D)They are not separated.

Question 65

How does the concentration of a reactant influence a zero-order reaction?

A)It increases the rate.
B)It decreases the rate.
C)It does not affect the rate.
D)There is not enough information to tell.

Question 66

The oxidation of ethanol (the alcohol found in alcoholic beverages) by the human body is what type of reaction?

A)An acid-base reaction
B)A neutralization reaction
C)A first-order reaction
D)A zero-order reaction

Question 67

What enzyme catalyzes the oxidation of ethanol in the body?

A)Alcohol dehydrase (ADH)
B)Alcohol dehydrogenase (ADH)
C)Alcohol hydrodeoxygenase (AHD)
D)Alcohol hydrogenase (AHD)

Question 68

What is an enzyme?

A)A large molecule that acts as a catalyst within a living system
B)A large molecule that acts as a filter within a living system
C)A molecule that acts as a catalyst within any system
D)A molecule that acts heterogeneously within a living system

Question 69

Enzyme catalysis is a common class of what type of reaction?

A)Zero order
B)First order
C)Second order
D)First order to each reactant

Question 70

How are zero-order reactions accelerated?

A)By adding more reactants
B)By decreasing product as it is formed
C)By adding a catalyst
D)None of the above

Question 71

In the reaction N₂ + 3 H₂ → 2 NH₃, the addition of nitrogen to the reaction does not speed up the reaction rate. What type of reaction can this be considered with respect to nitrogen?

A)An acid-base reaction
B)A zero-order reaction
C)A second-order reaction
D)A biphasic reaction

Question 72

In a certain reaction, the concentration of a single reactant is doubled and the rate goes up by a factor of 4. What is the order of the reaction with respect to that reactant?

A)0
B)1
C)2
D)None of the above.

Question 73

If a reaction has two reactants, and doubling the concentration of one of them doubles the reaction rate, while doubling the concentration of the other leaves the reaction rate unchanged, what is the order of the reaction?

A)0
B)½
C)2
D)1 with respect to the first reactant, and 0 with respect to the second

Question 74

What happens to the rate of a first-order reaction when a reactant concentration is doubled?

A)Nothing.
B)It is halved.
C)It doubles.
D)It quadruples.

Question 75

What does collision theory predict will occur when reactant concentration is increased?

A)It will increase.
B)It will stay the same.
C)It will decrease.
D)It makes no prediction about this.

Question 76

When cocaine is eliminated from a human body, reaction concentration drops much faster at the outset than at later times. Of what type of reaction is this indicative?

A)A zero-order reaction
B)A first-order reaction
C)An elimination reaction
D)This makes no indication of reaction type.

Question 77

If a reaction rate doubles when the reactant concentration doubles, even when catalyzed by an enzyme, what type of reaction is it?

A)A neutralization
B)Zero order
C)First order
D)An oxidation

Question 78

What type of reaction order do most pharmaceuticals follow?

A)First order
B)Zero order
C)Enzymatic
D)Catalytic

Question 79

What is the symbol for half-life?

A)hl
B)Hl_½
C)t_½
D)Tl_½

Question 80

If a person takes a pain reliever with a 2.5 hour half-life at 1:00 P.M., at what time will three half-lives have expired?

A)3:30 P.M.
B)6:00 P.M.
C)8:30 P.M.
D)None of the above.