practice questions on carboxylic acids

8/12/2019 Practice Questions on Carboxylic Acids

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Carboxylic Acids

1) The combination of a carbonyl group and a hydroxyl group on the same carbon atom is calleda __________ group.

A) carbamate

B) carbonateC) urethane

D) carboxyl

E) carboxylateAnser! D

Diff! 1

") The common name for pentanedioic acid is!

A) pimelic acid

B) oxalic acid

C) glutaric acidD) succinic acid

E) adipic acidAnser! C

Diff! "

#) $ro%ide the structure of #'dimethylheptanoic acid.

Anser! C(#C("C("C("CC(#)"C("C*"(

Diff! 1

+) $ro%ide the structure of glutaric acid.

Anser!

Diff! "

,) $ro%ide the name of the compound shon belo.

Anser! "&,'dimethyl'+'hexenoic acid or "&,'dimethylhex'+'enoic acid

Diff! "

1


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-) $ro%ide the /$AC name for (*"CC("CC(#)"C("C("C*"(.

Anser! 'dimethylhexanedioic acid

Diff! 1

0) $ro%ide the /$AC name for the compound shon belo.

Anser! o'hydroxybenoic acid or "'hydroxybenoic acid

Diff! 1


Anser! E'"&,'dimethyloct','enoic acidDiff! 1


Anser! 'hydroxyhexanoic acid

Diff! 1

14) $ro%ide the structure of trans'1'cyclohexanedicarboxylic acid.Anser!

Diff! 1

11) $ro%ide the structure of pent'#'ynoic acid.Anser! C(#C5CC("C*"(

Diff! 1

"


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1") $ro%ide the structure of #'nitrophthalic acid.

Anser!

Diff! 1

1#) $ro%ide the structure of succinic acid.

Anser! (*"C C("C("C*"(

Diff! "

1+) Carboxylic acids boil at considerably higher temperatures than do alcohols& 6etones& or

aldehydes of similar molecular eights. This is because they!A) ha%e a greater oxygen content.

B) are more acidic.

C) form stable hydrogen'bonded dimers.D) are hydrophobic.

E) none of the abo%e.

Anser! CDiff! 1

1,) Are carboxylic acids of more than 14 carbons more soluble in polar or nonpolar sol%ents7

Anser! nonpolar sol%ents

Diff! 1

1-) Dra an acetic acid dimer. Be sure to indicate the hydrogen bonds present.

Anser!

Diff! "

#


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10) 8hy are the *( groups of carboxylic Acids more acidic than alcohols7

A) resonance stabiliation of the carboxylate ion

B) inducti%e electron donating by the carbonyl oxygenC) reduced hydrogen bonding capacity

D) because they ha%e loer p9a %alues

E) none of the abo%e ' carboxylic acids are not more acidic than alcoholsAnser! A

Diff! 1

12) :ist the folloing ea6 acids in order of increasing acidity from loest to highest.).

A) + ; # ; " ; 1 ; ,

B) + ; 1 ; # ; " ; ,C) , ; " ; # ; 1 ; +

D) + ; 1 ; " ; , ; #

E) 1 ; " ; + ; # ; ,Anser! B

Diff! 1

13) 8hich of the folloing is the strongest acid7A) acetic acid

B) chloroacetic acidC) bromoacetic acid

D) fluoroacetic acid

Anser! DDiff! "

"4) 8hich of the folloing is the strongest acid7

A) chloroacetic acid

B) dichloroacetic acidC) trichloroacetic acid

D) acetic acid

Anser! C

Diff! "

+


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"1) The strongest dichlorobutanoic acid is!

A) "&"'dichlorobutanoic acid

B) "'dichlorobutanoic acidC) #'dichlorobutanoic acid

D) #&+'dichlorobutanoic acid

E) +&+'dichlorobutanoic acidAnser! A

Diff! "

"") 8hich of the folloing compounds is the strongest acid7

A) p'nitrobenoic acidB) p'bromobenoic acid

C) m'methylbenoic acid

D) m'methoxybenoic acidE) ater

Anser! A

Diff! "

"#) 8hich of the folloing is the strongest acid7

A) C(#)"C(C*"(

B) C(#C("C*"(

C) C(#*C("C*"(

D) $hC("C*"(

E) *"


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",) At p( +.,& hich of the folloing acids ould be most dissociated7

A) p'nitrobenoic acid p9a> #.+1)

B) acetic acid ethanoic acid) p9a> +.0+)

C) hexanoic acid p9a> +.22)

D) octanoic acid p9a> +.23)

E) aterAnser! A

Diff! #

"-) 8hat salt results from the reaction of benoic acid ith potassium hydroxide7

Anser! potassium benoateDiff! 1

"0)


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#4) After completing the synthesis of #'methylpentanoic acid& hich of the folloing treatments

ill neutralie the mineral acids and facilitate the distribution of the organic acid from the

organic layer to the a=ueous extraction layer7A) Extraction ith a=ueous


8/23

#,) /sing acid'base extractions& ho might you purify a crude sample of benoic acid7

Anser!

1. Dissol%e sample in ether.". Extract ith ater to remo%e ater'soluble impurities.

#. Extract ith sodium bicarbonate to separate benoate from organic impurities.

+. Acidify a=ueous layer and extract benoic acid into ether.,. Dry ether layer& filter to remo%e drying agent& and e%aporate ether to gi%e purified benoic

acid.

Diff! "

#-) 8here ould one expect to find the 1(


9/23

#3) 8hat to features are prominent in the infrared spectrum of a carboxylic acid7

Anser! The carbonyl stretch at H1014 cm'1and the hydroxyl stretch beteen ",44 and

#,44 cm'1.Diff! 1

+4) (o does the *'( stretch in the F spectrum of a carboxylic acid differ from the *'( stretch

of an alcohol7

Anser! The *'( stretch of a carboxylic acid is broader and shifted to loer a%enumbers.Diff! "

+1) Deduce a reasonable structure for the compound hich exhibits the folloing spectroscopicdata.

C,(3Cl*"! F! "044'#+44 cm'1broad)& 1014 cm'1I 1(


10/23

++) An acid hich could not be prepared from an organic halide by carboxylation of the

Jrignard reagent is!

A) benoic acidB) "&"'dimethylpropanoic acid

C) propanoic acid

D) +'oxocyclohexanecarboxylic acidE) "'methylbutanoic acid

Anser! D

Diff! "

+,) 8hat compound is produced hen cyclohexene is treated ith concentrated 9n*+7

A) hexanoic acidB) adipic acid

C) cyclohexanecarboxylic acid

D) benoic acid

E) succinic acidAnser! B

Diff! "

+-) 8hat compound is produced hen C(#)"C(C("Br is sub@ected to the folloing se=uence

of steps! 1. g& Et"*& ". C*"& #. (#*?7

A) "'methylpropanoic acid

B) #'methylpropanoic acid

C) "'methylbutanoic acidD) #'methylbutanoic acid

E) "'methylhexanoic acidAnser! DDiff! "

14


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+2) 8hich se=uence of steps belo describes the best synthesis of ,'oxohexanoic acid starting

ith 1'methylcyclopentan'1'ol

A) 1. Conc. 9n*+". Dry gaseous (Br

#. mgKether

+. C*"

B) 1. ("L*+and heat

". Conc. 9n*+C) 1. Conc. 9n*+

". C(#gBrK ether

#. (#*?

D) 1. ("L*+and heat

". *##. C(#)"L

+. $CC

E) 1. ("L*+and heat

". Conc. 9n*+

#. :iAl(+

+. (#*?

Anser! BDiff! #

11


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,#) $ro%ide the ma@or organic product of the folloing reaction.

Anser!

Diff! "

,+) $ro%ide the ma@or organic product of the folloing reaction se=uence.

Anser!

Diff! "

,,) $ro%ide the ma@or organic product of the folloing reaction se=uence.

Anser!

Diff! "

1#


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,-) $ro%ide the ma@or organic product of the folloing reaction se=uence.

Anser!

Diff! "

,0) $ro%ide the se=uence of reagents needed to accomplish the con%ersion belo.

Anser!1. B(#MT(N

". ("*"& (*'

#.


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,3) $ro%ide the ma@or organic product of the reaction shon belo.

Anser!

Diff! "

-4) $ro%ide the ma@or organic product of the reaction shon belo.

Anser!

Diff! "

-1) $ro%ide the ma@or organic product of the reaction shon belo.

Anser!Diff! "

1,


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17/23

-0) "'$henylethanol yields hat acid upon treatment ith hot chromic acid or permanganate7

Anser! benoic acid

Diff! "

-3) $ropose a reasonable synthetic route to prepare cyclohexylacetic acid frommethylenecyclohexane.

Anser!

1. (Br& peroxides

". g& ether#. C*"

+. (?& ("*

or

1. (Br& peroxides

".


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0#) 8hich of the folloing conditions ill dri%e the e=uilibrium of the Nischer esterification

toards ester formation7

A) addition of aterB) remo%al of ater as it is formed

C) addition of an inorganic acid as a catalyst

D) addition of alcoholE) both B and D

Anser! E

Diff! # 4

0+) $ro%ide the ma@or organic product of the reaction shon belo.

Anser!

Diff! "

4

0-) The methyl ester of a carboxylic acid can be synthesied directly using!

A) L*Cl"B) $Cl,C) C"*"Cl"D) C(

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practice questions on carboxylic acids

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