Deck 13: Chemical Kinetics Clearing the Air

Question 1

Which compound below is NOT a component of photochemical smog?

A)O₃
B)N₂
C)NO₂
D)NO
E)organic molecules

Answer 1

N₂

Question 2

What is the device in an automobile that decreases the amount of NO and partially oxidized hydrocarbons in exhaust gases?

A)a catalytic intermediate
B)a photochemical inhibitor
C)a homogeneous catalyst
D)a nitrogen monoxide reducer
E)a catalytic converter

Answer 2

a catalytic converter

Question 3

Which statement below regarding catalytic converters is FALSE?

A)A catalytic converter targets compounds such as hydrocarbons, carbon monoxide, and nitrogen oxide compounds.
B)Reactions that reduce the amounts of hazardous by-products of the combustion reactions in automobiles occur very rapidly in the catalytic converter.
C)CO is usually oxidized to CO₂ in one stage of the catalytic converter.
D)N₂ is oxidized to nitrogen oxides in the catalytic converter.
E)Hydrocarbons are usually oxidized to CO₂ and H₂O in the catalytic converter.

Answer 3

N₂ is oxidized to nitrogen oxides in the catalytic converter.

Question 4

The greatest NO concentration is observed

A)in the morning before rush hour.
B)in the morning just after rush hour.
C)in midmorning.
D)at noon.
E)in midafternoon.

Question 5

A scientist conducts an experiment to determine the rate of NO formation in the following reaction: 2 N₂O₅(g) $\rightarrow$ 4 NO₂(g) + O₂(g)
If the initial concentration of N₂O₅ was 0.500 M and the concentration of N₂O₅ was 0.450 M after 0.100 s, what is the average rate of NO₂ formation during the first 100 milliseconds?

A)0.25 M/s
B)0.50 M/s
C)1.0M/s
D)5.0 M/s
E)10.0 M/s

Question 6

Smog created by the interaction of sunlight with nitrogen oxides and volatile organic compounds is termed smog.

A)photolytic
B)photochemical
C)photophysical
D)acidic
E)sulfurous

Question 7

Which compound below is a component of photochemical smog?

A)N₂
B)CO₂
C)N₂O
D)O₃
E)CO

Question 8

The order in which ozone, nitrogen monoxide, and nitrogen dioxide build up in the atmosphere over the course of the day is then then

A)NO; NO₂; O₃.
B)NO; O₃; NO₂.
C)NO₂; NO; O₃.
D)NO₂; O₃; NO.
E)O₃; NO; NO₂.

Question 9

NO₂ contributes to the "brown haze" associated with photochemical smog events.At what time of day is NO₂ concentration highest?

A)in the morning before rush hour
B)in the morning just after rush hour
C)midmorning
D)noon
E)midafternoon

Question 10

Which of the following is NOT important as a contributing factor to photochemical smog?

A)stagnant air
B)sunlight
C)a lot of traffic
D)irrigation
E)cars without catalytic converters

Question 11

Which statement below regarding the average rate of a reaction is FALSE?

A)The change in concentration of reactant or product is not always linear with time.
B)The average reaction rate usually decreases as the reaction proceeds.
C)The average reaction rate can be determined from the slope of a line drawn between two points on a plot of concentration versus time.
D)The average reaction rate can be determined from the slope of the tangent line drawn at time = 0 on a plot of concentration versus time.
E)The average rate usually depends on the concentrations of reactants.

Question 12

The following graph shows the kinetics curves for the reaction of oxygen with hydrogen to form water: O₂(g) + 2 H₂(g) $\rightarrow$ 2 H₂O(g).Which curve is hydrogen?

A)the dashed curve
B)the gray curve
C)the black curve
D)either the gray or the black curve
E)Any of these curves could be hydrogen.

Question 13

A scientist conducts an experiment to determine the rate of the following reaction: 2 N₂(g) +O₂(g) $\rightarrow$ 2 N₂O(g)
If the initial concentration of N₂ was 0.400 M and the concentration of N₂ was 0.350 M after 0.100 s, what is the average rate of reaction over the first 100 milliseconds?

A)0.25 M/s
B)0.50 M/s
C)1.0 M/s
D)5.0 M/s
E)10.M/s

Question 14

Which reaction below is NOT important in the production of photochemical smog?

A)H₂O₂(g) + O₂(g) $\rightarrow$ O₃(g) + H₂Og)
B)N₂(g) + O₂(g) $\rightarrow$ 2 NO(g)
C)O₃(g) + NO(g) $\rightarrow$ O₂(g) + NO₂(g)
D)NO₂(g) $\rightarrow$ NO(g) + O(g)
E)N₂(g)+ 3 O₂(g) + OH(g) + CH₃CHO(g) $\rightarrow$ (CH₃O)O₂NO₂ (g) + H₂O(g) + NO₂(g)

Question 15

HI dissociates to form I₂ and H₂: 2 HI(g) $\rightarrow$ H₂(g+I₂(g). If the concentration of HI changes at a rate of -0.45 M/s, what is the rate of appearance of I₂(g)?

A)0.90 M/s
B)0.45 M/s
C)0.23 M/s
D)1.0 M/s
E)0.13 M/s

Question 16

Which statement below regarding the difference between an average rate and an instantaneous rate is FALSE?

A)The average rate is taken over a larger time period.
B)The instantaneous rate is taken from the slope of the curve at a specific time.
C)They are not different if the time interval chosen is small enough.
D)The instantaneous rate is always faster than the average rate.
E)Both tend to decrease as the reaction proceeds.

Question 17

At what time of day are ozone concentrations highest during a photochemical smog event?

A)in the morning before rush hour
B)in the morning just after rush hour
C)midmorning
D)noon
E)midafternoon

Question 18

Large cities often issue ozone advisories.At what time of year would an advisory be likely to occur most often?

A)winter
B)spring
C)summer
D)fall
E)No season should have more advisories than another.

Question 19

A scientist conducts an experiment to determine the rate of the following reaction: 2 N₂O₅(g) $\rightarrow$ 4 NO₂(g) +O₂(g)
If the initial concentration of NO₂ was 0.000 M and the concentration of NO₂ was 0.050 M after 0.100s, what is the average rate of reaction over the first 100 milliseconds?

A)0.13 M/s
B)0.50 M/s
C)1.0 M/s
D)2.0.M/s
E)5.M/s

Question 20

Which statement below regarding the determination of reaction rates is true?

A)Reaction rates can be measured by monitoring how much product is generated or how much reactant is consumed in a given amount of time.
B)Reaction rates can be completely predicted based on the stoichiometry of a reaction.
C)The reaction rate determined at one instant during the course of a reaction is the same as at any other instant.
D)Experimentally determined reaction rates do not depend on factors other than concentration.
E)The average rate of reaction does not vary.

Question 21

If the average rate of reaction for 2 N₂O₅(g) $\rightarrow$ 4 NO₂(g) + O₂(g) is 1.30 *10^-5 M/s over five minutes of the reaction, what is the partial pressure of NO₂ after the first 5.00 minutes if the reaction takes place in a 10.0 L vessel maintained at 55.0 $\degree$ C?

A)0.420 atm
B)0.105 atm
C)0.156 atm
D)0.0704 atm
E)0.084 atm

Question 22

The initial rate of a chemical reaction depends on which factors) below? I.concentration of reactants
II)concentration of products
III)temperature

A)I
B)III
C)II
D)both I and III
E)I, II, and III

Question 23

For the reaction 4 NH₃ (g)+ 7 O₂ (g) $\rightarrow$ 4 NO₂(g) + 6 H₂(g), if H₂ is produced at a rate of 3.5 * 10^-3 M/s, O₂ is consumed at a rate of

A)(-2.5 * 10^-2 M/s.)
B)(-2.1* 10^-2 M/s.)
C)(-4.1 *10^-3 M/s.)
D)(-3.0 *10^-3 M/s.)
E)(-5.8 *10^-4 M/s.)

Question 24

Which statement below regarding reaction rates and kinetic molecular theory is FALSE?

A)Higher concentrations of reactants typically lead to greater reaction rates because a larger number of effective molecular collisions occur.
B)Collisions between product molecules that reform reactant molecules do not affect the overall rate of reaction.
C)The actual dependence of reaction rate on concentration must be determined experimentally because it depends on the reaction mechanism.
D)At t = 0, the maximum rate should be observed because only reactant molecules are present.
E)As the reaction proceeds, fewer reactant molecules are present and the reaction rate typically decreases.

Question 25

Ammonia gas (NH₃) is produced from hydrogen and nitrogen gas according to the following reaction: 3 H₂(g) + N₂(g) $\rightarrow$ 2 NH₃(g)
If the rate of production of ammonia is R(NH₃), what is the rate of loss of hydrogen and nitrogen gas, respectively?

A)(-R(H₂) = 2/3 R(NH₃); -R(N₂) = 1/2 R(NH₃))
B)(-RH₂) = 3/2 R(NH₃); -R(N₂) = 2 R(NH₃))
C)(-R(H₂) =3/2 R(NH₃); -R(N₂)= 1/2 R(NH₃)
D)(-R(H₂)= 2/3 R(NH₃); -R(N₂) = 2 R(NH₃))
E)(-R(H₂) =R(NH₃); -R(N₂) = R(NH₃))

Question 26

In the reaction CL₂(g) + 3F₂(g) $\rightarrow$ 2ClF₃(g), if the average rate of disappearance of F₂ is -0.250 M/s over the first 6.00 s, how much ClF₃ will form during this time?

A)0.750 M
B)1.00 M
C)1.50 M
D)2.00 M
E)3.00 M

Question 27

The rate of a reaction is found to triple when the concentration of one reactant is tripled.The order of the reaction with respect to this reactant is

A)first.
B)second.
C)zero.
D)one-half.
E)third.

Question 28

The reaction CHCl₃(g) +CL₂(g) $\degree$ CCL₄(g) + HCl(g) has the following rate law: Rate =k[CHCl₃][Cl₂].If the concentration of CHCl₃ is increased by a factor of five while the concentration of Cl₂ is kept the same, the rate will

A)double.
B)triple.
C)stay the same.
D)increase by a factor of five.
E)decrease by a factor of one-fifth.

Question 29

For the reaction 3A+ 5B $\rightarrow$ 2C + 4 D, which reaction rate relationship is true?

A) $\frac{\Delta[\mathrm{C}]}{\Delta t}=\frac{2}{5} \frac{\Delta[\mathrm{B}]}{\Delta t}$

B) $\frac{\Delta[\mathrm{B}]}{\Delta t}=\frac{5}{4} \frac{\Delta[\mathrm{D}]}{\Delta t}$

C) $\frac{\Delta[\mathrm{D}]}{\Delta t}=\frac{4}{3} \frac{\Delta[\mathrm{A}]}{\Delta t}$

D) $\frac{\Delta[\mathrm{A}]}{\Delta t}=\frac{3}{5} \frac{\Delta[\mathrm{B}]}{\Delta t}$

E) $\frac{\Delta[\mathrm{B}]}{\Delta t}=-\frac{3}{5} \frac{\Delta[\mathrm{A}]}{\Delta t}$

Question 30

The rate of disappearance of HI in the reaction 2 HI(g) $\rightarrow$ I₂(g) +H₂(g) is shown in the following figure.Estimate the instantaneous rate of this reaction at t =5 s.

A)0.2 M/s
B)0.01 M/s
C)0.02 M/s
D)0.1 M/s
E)0.04 M/s

Question 31

The rate of a reaction is found to increase nine-fold when the concentration of one reactant is tripled. The order of the reaction with respect to this reactant is

A)first.
B)second.
C)one-quarter.
D)one-half.
E)third.

Question 32

Which statement below is true about the instantaneous rate for the chemical reaction A $\rightarrow$ B as the reaction progresses?

A)(- $\Delta$ [A]/ $\Delta$ t increases while $\Delta$ [B]/ $\Delta$ t decreases.)
B)(- $\Delta$ [A]/ $\Delta$ t decreases while $\Delta$ [B]/ $\Delta$ t increases.)
C)Both- $\Delta$ [A]/ $\Delta$ t and $\Delta$ [B]/ $\Delta$ t decrease.
D)Both- $\Delta$ [A]/ $\Delta$ t and $\Delta$ [B]/ $\Delta$ t increase.
E)The answer will vary depending on the reaction mechanism.

Question 33

Approximately how many times faster or slower is the average reaction rate during the first four seconds (t =0 to t = 4) than the second four seconds t = 4 to t = 8) for the following reaction? 2 NOBr(g) $\rightarrow$ Br₂ (g) + 2 NO(g)

A)about 1.4 times faster
B)about 1.4 times slower
C)about 2.64 times slower
D)about 2.6 times faster
E)The average rate is constant.

Question 34

Given the following data, determine the order of the reaction with respect to ICl. H₂(g) + 2 ICl(g) $\rightarrow$ I₂ (g) +2 HCl(g)

A)one-half
B)first
C)second
D)third
E)three-halves

Question 35

The reaction 2 NO(g) +O₂(g) $\rightarrow$ 2 NO₂(g) has the following rate law: Rate =k[O₂][NO]².If the concentration of NO is reduced by a factor of two while the concentration of O₂ is doubled, the rate will

A)double.
B)quadruple.
C)decrease by a factor of one-fourth.
D)decrease by a factor of one-half.
E)remain the same.

Question 36

The rate of a reaction is found to double when the concentration of one reactant is quadrupled.The order of the reaction with respect to this reactant is

A)first.
B)second.
C)one-quarter.
D)one-half.
E)third.

Question 37

The rate of disappearance of HI in the reaction 2 HI(g) $\rightarrow$ I₂(g)+H₂(g) is shown in the following figure.What is the approximate average rate of reaction over the first 15.0 seconds of the reaction?

A)0.275 M/s
B)0.138 M/s
C)0.0117 M/s
D)0.00917 M/s
E)0.0183 M/s

Question 38

Given the following data, determine the order of the reaction with respect to Cl₂. 2 NO(g) +CL₂(g) $\rightarrow$ 2 NOCL₂(g)

A)first
B)second
C)third
D)fourth
E)zero

Question 39

In a rate law, the partial orders are determined by

A)the reactant concentrations.
B)the stoichiometric coefficients.
C)the product concentrations.
D)experimentation.
E)the difference between the forward and reverse rates.

Question 40

Given the following data, determine the order of the reaction with respect to NO(g). 2 NO(g) +CL₂(g) $\rightarrow$ 2 NOCL₂(g)

A)first
B)second
C)third
D)fourth
E)zero

Question 41

The reaction C₂ H₅ Cl(g) $\rightarrow$ C₂ H₄ (g) + HCl(g) has a rate constant of approximately 4.20 *10^-5 s^-1 at 700 K.What is the reaction rate if 123.8 g of C₂H₅Cl is placed in an 8.00 L container at 700 K?

A)1.75 * 10^-4 M/s
B)3.36 * 10^-4 M/s
C)6.50 * 10^-4 M/s
D)1.01 * 10^-5 M/s
E)8.01 * 10^-5 M/s

Question 42

The second-order reaction A $\rightarrow$ B is found to have a rate constant of 0.560 M^-1 s^-1.What is the half-life of this reaction when [A]₀ = 0.0450 M?

A)0.0252 s
B)1.24 s
C)12.4 s
D)24.9 s
E)39.7 s

Question 43

Determine the overall order of the reaction CH₃ CHO (g) $\rightarrow$ CH₄ (g) + CO(g) from the following data:

A)one-half
B)first
C)second
D)three-halves
E)third

Question 44

The rate of disappearance of HI in the reaction 2 HI(g) $\rightarrow$ I₂ (g) +H₂ (g) is shown in the following figure.Estimate the initial rate of reaction.

A)0.350 M/s
B)0.140 M/s
C)0.035 M/s
D)0.175 M/s
E)0.070 M/s

Question 45

The half-life (t_1/2) of a first-order reaction is 0.100 s.What is the rate constant?

A)6.93 s^-1
B)0.693 s^-1
C)0.0693 s^-1
D)0.144 s^-1
E)3.01 s^-1

Question 46

Determine the overall order of the reaction 2 NO(g) + Cl₂ (g) $\rightarrow$ 2 NOCl(g) from the following data.

A)first
B)second
C)third
D)three-halves
E)fourth

Question 47

Given the following data, determine the rate law for the reaction 2 NO(g) + CL₂ (g) $\rightarrow$ 2 NOCl(g).

A)k[NO][Cl₂]
B)k[NO][Cl₂]²
C)k[NO]²[Cl₂]
D)k[NO]²[Cl₂]²
E)k[NO][Cl₂]^1/2

Question 48

Suppose 2.00 g of azomethane (58.08 g/mol) is placed in a 2.50 L container at 425 $\degree$ C and allowed to decompose according to the first-order reaction CH₃ NNCH₃ (g) $\rightarrow$ C₂ H₆ (g) + N₂ (g).Initially, 0.0234 moles of C₂H₆ are produced per second.What is the rate constant?

A)0.588 s^-1
B)0.0468 s^-1
C)0.0138 s^-1
D)0.0344 s^-1
E)0.680 s^-1

Question 49

For the rate law Rate =k[A]^3/2[B], the partial order with respect to A is _______ , the partial order with respect to B is _______ , and the total order is _______ .

A) $\frac{3} {2}$ ; 0; $\frac{3} {2}$

B) $\frac{3} {2}$ ; 1;1

C) $\frac{3} {2}$ ; 1; $\frac{5} {2}$

D) $\frac{3} {2}$ ; 1; $\frac{7} {2}$

E)The orders cannot be determined without a chemical reaction.

Question 50

For the rate law Rate =k[A]^1/2[B], the partial order with respect to A is _______ , the partial order with respect to B is _______ , and the total order is _______ .

A) $\frac{1} {2}$ ;0 ; $\frac{1} {2}$

B) $\frac{1} {2}$ ; 1; 1

C) $\frac{1} {2}$ ; 1; $\frac{3} {2}$

D) $\frac{1} {2}$ ; 1; $\frac{5} {2}$

E)The orders cannot be determined without a chemical reaction.

Question 51

Which statement below regarding rate laws and rate constants is true?

A)The rate constant is independent of temperature.
B)The units of the rate constant depend on the stoichiometry of the reaction.
C)The rate constant typically depends on concentration of reactants).
D)The rate typically depends on concentration of reactants).
E)The rate constant does not change when a catalyst is introduced.

Question 52

Which of these could be the units for the rate constant in a second-order reaction?

A)M ^-1 s
B)M s^-1
C)M ^-1 s^-1
D)M ^-2 s^-1
E)M s

Question 53

A reaction is first order in A.If the rate constant of the reaction is 3.45 * 10^-3 s^-1, what is the half-life (t_1/2) of the reaction?

A)4.98 *10^-3 s
B)201 s
C)3.45 * 10^-3 s
D)100.0 s
E)1.73* 10^-3 s

Question 54

Determine the overall order of the reaction H₂ (g) + 2 ICl(g) $\rightarrow$ I₂ (g) $\rightarrow$ 2 HCl(g) from the following data:

A)first
B)second
C)third
D)fourth
E)zero

Question 55

Which of these could be the units of the rate constant for a third-order reaction?

A)M ^-1 s^-1
B)M s^-1
C)M ^-2 s^-1
D)M ^-3 s^-1
E)s^-1

Question 56

Given the following data, determine the order of the reaction with respect to Cl₂: CO(g) + Cl ₂ (g) $\rightarrow$ COCL₂ (g)

A)one-half
B)first
C)second
D)third
E)three-halves

Question 57

The second-order reaction A $\rightarrow$ B $\rightarrow$ C will obey pseudo-first-order kinetics when

A)the concentrations of A and B are both small.
B)the concentration of one of the reactants does not change.
C)the concentration of C is large.
D)the concentrations of A and B are both large.
E)a catalyst changes the mechanism to a first-order reaction.

Question 58

A second-order reaction (2 A $\rightarrow$ B) with a rate constant of 0.350 M^-1 s^-1 is found to have a half-life of 3.45 s.What was the initial concentration of the reactant, [A] ₀?

A)0.828 M
B)0.201 M
C)1.00 M
D)1.21 M
E)0.350 M

Question 59

The reaction A + 2B $\rightarrow$ C is first order in B and A.The overall order of the reaction is

A)first.
B)second.
C)third.
D)zero.
E)fourth.

Question 60

To determine the rate law for a reaction, data from several reactions run at different concentrations are usually required.For what type of reaction are data from just one experiment plotting concentration versus time sufficient to determine the rate law?

A)zero-order reactions
B)first-order reactions
C)second-order reactions
D)reactions with fractional orders
E)photochemical reactions

Question 61

For the first-order reaction 2 SO₂ Cl(g) $\rightarrow$ 2 SO₂ (g) +CL₂ (g), it takes 3.50 minutes for the concentration of SO₂Cl to decrease from 0.250 M to 0.205 M when the temperature is 25.0 $\degree$ C.How long will it take for the reaction to be 75.0% complete?

A)1.07 minute
B)5.07 minutes
C)13.2 minutes
D)14.6 minutes
E)24.4 minutes

Question 62

Nitrogen dioxide undergoes thermal decomposition according to the second-order reaction 2 NO₂ (g) $\rightarrow$ 2 NO (g) + O₂ (g).When 0.500 M NO₂ is allowed to react for 90.0 seconds, its concentration falls to 0.0196 M.What is the rate constant for the reaction?

A)0.00534 M^-1s^-1
B)0.589 M^-1s^-1
C)0.545 M^-1s^-1
D)0.0214 M^-1s^-1
E)0.0231 M^-1s^-1

Question 63

The half-life for a particular first-order reaction is 2.50 minutes at 25.0 $\degree$ C.How long will it take for the reaction to be 88.0% complete?

A)0.460 minute
B)2.84 minutes
C)4.40 minutes
D)7.63 minutes
E)8.94 minutes

Question 64

The second-order hydrolysis reaction of ethyl acetate, CH₃COOC₂H₅ (aq) +H₂ O(l) $\rightarrow$ CH₃ COOH(aq) + C₂ H₅ OH(aq), follows pseudo-first-order reaction kinetics in solutions in which the molarity of water is assumed to be roughly constant at 55.5 M.An experiment using an initial CH₃COOC₂H₅ concentration of 0.06500 M is conducted under pseudo-first-order conditions.After 60 seconds, [CH₃COOC₂H₅] = 0.05764 M.Estimate the second-order rate constant.

A)2.00 F*10^-3 M ^-1 s^-1
B)1.27 * 10^-3 M ^-1 s^-1
C)3.61* 10^-5 M ^-1 s^-1
D)0.111 M ^-1 s^-1
E)6.67 M ^-1 s^-1

Question 65

A zero-order reaction has a half-life of 10.0 minutes when the reactant concentration is 0.250 M.How many minutes will it take for the reaction to be 75.0% complete?

A)5.00 minutes
B)7.50 minutes
C)15.0 minutes
D)20.0 minutes
E)30.0 minutes

Question 66

The rate constant for the reaction 2 ClO(g) $\rightarrow$ CL₂ (g) +O₂ (g) is 7.22 * 10⁹ M^-1 s^-1 at a particular temperature.Suppose 0.0250 atm ClO is initially present in a reaction vessel containing air at STP (1 atm, 273 K).What is the half-life of this reaction?

A)5.54 * 10^-9 s
B)1.24* 10^-7 s
C)1.39 * 10^-10 s
D)1.81 F*10^-10 s
E)8.09 * 10^-12 s

Question 67

Nitrogen dioxide undergoes thermal decomposition according to the second-order reaction 2 NO₂ (g) $\rightarrow$ 2 NO(g) + O₂ .When 0.5000 M NO₂ is allowed to react for 9.00 minutes, its concentration falls to 0.0250 M.How long did it take for the concentration of NO₂ to fall to 0.2500 M?

A)0.474 minute
B)0.592 minute
C)2.08 minutes
D)4.22 minutes
E)4.74 minutes

Question 68

Collision theory assumes that the rate of a reaction depends on

A)the energy of collisions.
B)the orientation of colliding molecules.
C)the energy of collisions and the orientation of colliding molecules.
D)the change in energy between the products and the reactants.
E)the change in free energy between the reactants and the products.

Question 69

The energy needed to form an activated complex is called

A)collision energy.
B)kinetic energy.
C)potential energy.
D)activation energy.
E)thermodynamic energy.

Question 70

Given the following data, determine the rate law for the reaction H₂ (g) +2 ICl(g) $\rightarrow$ I₂ (g) + 2 HCl(g).

A)k[H₂][ICl]
B)k[H₂][ICl]²
C)k[H₂]²[ICl]
D)k[H₂]^1/2[ICl]^1/2
E)k[H₂][ICl]^1/2

Question 71

The half-life of radioactive carbon-14 is 5730 years.If the 14C level in a sample of organic matter has been reduced to 0.200% of its original value, approximately how much time has passed? Radioactive decay follows first-order kinetics.

A)1650 years
B)51,400 years
C)29,900 years
D)2,870,000 years
E)9220 years

Question 72

The rate constant for the decomposition reaction of H₂O₂ is 3.66 *10^-3 s^-1 at a particular temperature.What is the concentration of H₂O₂ (34.01 g/mol) in a solution that was initially 30.0% H₂O₂ by mass (with a density of 1.135 g/mL) after 15.0 minutes have passed?

A)9.47 M
B)0.270 M
C)0.0371 M
D)0.371 M
E)3.29 M

Question 73

The first-order reaction A $\rightarrow$ B has k = 0.210 min^-1.If [A]₀ =0.500 M, how long will it take [A] to equal 0.115 M ?

A)1.83 min
B)4.55 min
C)7.00 min
D)20.7 min
E)31.9 min

Question 74

Dinitrogen pentoxide rapidly decomposes in the atmosphere according to the reaction 2 N₂O₃ (g) $\rightarrow$ 2 N₂O₄ (g) + O₂ (g).At a particular temperature, the slope of a plot of ln [N₂O₅] versus time is -0.00693.How long will it take N₂O₅ to reach 0.100% of its original concentration if [N₂O₅]₀ = 0.0250 M ?

A)997 s
B)332 s
C)100 s
D)277 s
E)6.93 s

Question 75

Given the following data, determine the rate constant of the reaction 2 NO(g) + CL₂ (g) $\rightarrow$ 2 NOCl(g).

A)1.13 M ^-2s^-1
B)9.44 M ^-2s^-1
C)37.8 M ^-2s^-1
D)0.0265 M ^-2s^-1
E)59.6 M ^-2s^-1

Question 76

Dinitrogen pentoxide rapidly decomposes in the atmosphere according to the reaction 2 N₂O5 (g) $\rightarrow$ 2 N₂O₄ (g) + O₂ (g).At a particular temperature, the slope of a plot of ln[N₂O₅] versus time in seconds is-0.00693.What is the half-life of this reaction if [N₂O5 ]0 = 1.20 M?

A)100 s
B)120 s
C)4.79 s
D)72.2 s
E)86.6 s

Question 77

The rate constant for the reaction 2 ClO(g) $\rightarrow$ CL₂ (g) +O₂ (g) is 7.22 * 10⁹ M^-1s^-1 at a particular temperature.Suppose 0.0250 atm ClO is initially present in a reaction vessel containing air at STP (1 atm, 273 K).After 5.00 minutes, what is the concentration of ClO?

A)4.65 * 10^-11 M
B)8.80 *10^-4 M
C)2.17 F* 10¹² M
D)1.39 *10^-10 M
E)4.62 * 10^-13 M

Question 78

Nitrogen dioxide undergoes thermal decomposition according to the second-order reaction 2 NO₂ (g) $\rightarrow$ 2 NO(g) + O₂ (g).When 0.500 M NO₂ is allowed to react for 90.0 seconds, its concentration falls to 0.0196 M.What is the half-life of the reaction when [NO₂]₀ = 0.500 M?

A)0.273 s
B)1.27 s
C)3.67 s
D)3.40 s
E)86.6 s

Question 79

The half-life for the second-order decomposition reaction of 0.100 M HI to form H₂ and I₂ is 286.4 hours at a particular temperature.What is the rate constant for the reaction?

A)1.03 * 10⁶ M ^-1 s^-1
B)9.70 * 10^-8 M^-1 s^-1
C)3.49 * 10^-2 M ^-1 s^-1
D)2.86 * 10⁴ M ^-1 s^-1
E)9.70 * 10^-6 M ^-1 s^-1

Question 80

Given the following data, determine the rate constant, k, of the reaction H₂ (g) $\rightarrow$ 2 ICl(g) $\rightarrow$ I₂ (g) +2 HCl(g).

A)1.65 * 10^-5 torr^-1s^-1
B)6.06 * 10⁴ torr^-1s^-1
C)8.17 *10^-5 torr^-1s^-1
D)1.34 torr^-1s^-1
E)3.48*10³ torr^-1s^-1