chemistry ch 16 whitten 10th edition

8/9/2019 chemistry ch 16 whitten 10th edition

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CHM 2046 Chapter 16 Homework

This homework will be graded by Canvas. To obtain credit, enter you answer key on

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C

Multiple Choice

Identify the choice that best completes the statement or answers the question.

)))) 1. *ne o# the reactions that is $sed to prod$ce gaseo$s hydrogen commercially #ollows. ! proper e+pression #or

the rate o# this reaction could be )))).

H2*,g- C*,g- → H2,g- C*2,g-

a.

b.

c. k

d.

e.

)))) 2. /n the #ollowing reaction% −0. mol3•s. 5hat is the val$e o# the rate o# the reaction at this time

! 78 → !87

a. 0.70 mol3•s

b. 0. mol3•s

c. −0.70 mol3•s

d. 2.69 mol3•s

e. 0.22 mol3•s

)))) 7. Consider the e+othermic comb$stion o# coal. 5hich o# the #ollowing co$ld increase the rate o# reaction

a. $sing smaller pieces o# coal b. increasing the concentration o# o+ygen

c. lowering the temperat$re

d. both ,a- and ,b- are correct

e. choices ,a-% ,b- and ,c- are all correct

)))) 4. 5hich response below is not an e+ample o# how the nat$re o# reactants a##ects the rate o# reactiona. :raphite b$rns #aster than diamond $nder e($al conditions.

b. Coal d$st b$rns #aster than large ch$nks o# coal.

c. Magnesi$m reacts #aster in higher concentrations o# HCl,a(-.

d. Calci$m reacts #aster in water than magnesi$m.

e. 5hite phosphor$s reacts e+plosively on contact with air; red phosphor$s does not.


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)))) −

,a(- → HC>,a(-

)))) 6. The gas phase reaction ! 8 → C has a reaction rate which is e+perimentally observed to #ollow the

relationship rate k ?!@?8@2. The overall order o# the reaction

a. is #irst.

b. is second.

c. is third.

d. is 'ero.

e. cannot be determined.

)))) 9. Consider the #ollowing rate law e+pressionA rate k ?!@?8@2. /# the concentration o# ! is tripled and the

concentration o# 8 is red$ced by hal#% what is the res$lting change in the reaction rate

a. The rate is increased by 732.

b. The rate is red$ced by 734.

c. The rate stays the same.

d. The rate is do$bled.

e. The rate is red$ced by 132.

)))) . The gasBphase reaction

2>* 2H2 → >2 2H2*

has the #ollowing rate law e+pression% rate k ?>*@2?H2@. /# the ?>*@ is halved and the ?H2@ is tripled% what

change in rate is e+pected

a. decrease by 734

b. increase by 734

c. increase by 732

d. decrease by 732e. stays same

)))) . The hal#Bli#e #or the reactant ! in the #irst order reaction below is 76.2 seconds. 5hat is the rate constant #or

this reaction at the same temperat$re

!→ 8

a. *2 is 1.0*2 → >2*4

a. 20.< s

b. 10.7 s

c. 0.741 min


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d. 196 s

e. 14. s

)))) 11. The decomposition o# dimethylether at


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d. 97.0 s

e.


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c. the n$mber o# moles o# transition state that m$st be #ormed

d. the energy o# the #orward reaction

e. the energy o# the reverse reaction

)))) 21. :iven the #ollowing potential energy diagram #or the oneBstep reaction

I J → K E

The arrow LcL represents the )))).

a. net energy o# reaction #or the #orward reaction b. activation energy #or the #orward reaction

c. net energy o# reaction #or the reverse reaction

d. activation energy #or the reverse reaction

e. energy content #or the reaction

)))) 22. 5hich o# the #ollowing statements abo$t reaction mechanisms is #alsea. ! reaction can have more than one possible mechanism.

b. ! reaction mechanism m$st be consistent with the e+perimentally observed rate law.

c. The slowest step in the reaction mechanism is called the rateBdetermining step.

d. Eeaction mechanisms involve comple+ reaction steps.

e. Eeaction mechanisms are di##ic$lt to prove.

)))) 27. ! reaction mechanism will $s$ally bea. the only possible e+planation #or the reaction.

b. di##ic$lt to veri#y e+perimentally.

c. generally obvio$s #rom the balanced chemical e($ation.

d. obvio$s #rom a consideration o# the balanced chemical e($ation.

e. obvio$s #rom a consideration o# the reaction rate data.

)))) 24. F$ppose the activation energy o# a certain reaction is 2


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a. 0.72 s−1

b. 91. s−1

c. 0.266 s−1

d. 1.0 s−1

e. 0.026< s−1

)))) 26. The rate constant% k % #or a #irstBorder reaction is 1.20 × 102 s−1 at 4

chemistry ch 16 whitten 10th edition

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