Organic Chemistry, 7e (Bruice)
Chapter 4 Isomers: The Arrangement of Atoms in Space
1) What type of isomers are CH
3
CH
2
OCH
3
and CH
3
CH
2
CH
2
OH?
A) constitutional
B) symmetrical
C) configurational
D) conformational
) stereochemical
Ans!er" A
#ection" $%1
2) What is the relationship &et!een the follo!ing compounds?
A) configurational isomers
B) conformational isomers
C) constitutional isomers
D) structural isomers
) positional isomers
Ans!er" A
#ection" $%1
3) What is the relationship &et!een the follo!ing compounds?
A) constitutional isomers
B) enantiomers
C) diastereomers
D) conformational isomers
) superimposa&le !ithout &ond rotation
Ans!er" A
#ection" $%1
1
Copyright ' 2(1$ )earson ducation* +nc,
$) What is the relationship &et!een the structures sho!n &elo!?
A) not isomers
B) constitutional isomers
C) conformational isomers
D) configurational isomers
) enantiomers
Ans!er" B
#ection" $%1
-) What is the relationship &et!een the structures sho!n &elo!?
A) diastereomers
B) constitutional isomers
C) conformational isomers
D) configurational isomers
) enantiomers
Ans!er" B
#ection" $%1
.) +dentify the pair of compounds,
A) identical
B) conformation isomers
C) constitutional isomers
D) configurational isomers
) none of the a&o/e
Ans!er" D
#ection" $%1
2
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0) Which of the follo!ing cannot e1hi&it chirality?
A) 2* 3%di&romo&utane
B) 1* 3%di&romo&utane
C) 1* 2%dichloro&utane
D) 1* $%di&romo&utane
) 1%&romo%2%chloro&utane
Ans!er" D
#ection" $%2
3
Copyright ' 2(1$ )earson ducation* +nc,
2) Which of the follo!ing compounds is chiral?
A)
B)
C)
D)
)
Ans!er" B
#ection" $%2
$
Copyright ' 2(1$ )earson ducation* +nc,
3) +s the molecule sho!n &elo! chiral or achiral?
Ans!er" achiral
#ection" $%2
1() +s the molecule sho!n &elo! chiral or achiral?
Ans!er" chiral
#ection" $%2
11) +s the molecule sho!n &elo! chiral or achiral?
Ans!er" achiral
#ection" $%2
12) +s the molecule sho!n &elo! chiral or achiral?
Ans!er" achiral
#ection" $%2
-
Copyright ' 2(1$ )earson ducation* +nc,
13) +dentify the compounds that are not chiral,
Ans!er" A* B* and D
#ection" $%2
1$) Which of the follo!ing compounds has an asymmetric center?
A) +
B) ++
C) +++
D) +4
) 4
Ans!er" C
#ection" $%3
1-) Ho! many asymmetric centers are present in a molecule of 2*$*.%trimethylheptane?
A) (
B) 1
C) 2
D) 3
) $
Ans!er" A
#ection" $%3
.
Copyright ' 2(1$ )earson ducation* +nc,
1.) Ho! many asymmetric centers are present in the compound sho!n &elo!?
A) 1
B) 2
C) 3
D) $
) -
Ans!er" C
#ection" $%3
10) Ho! many asymmetric centers are present in the compound &elo!?
Ans!er" -
#ection" $%3
12) +dentify the pair of compounds,
A) identical
B) conformational isomers
C) constitutional isomers
D) configurational isomers
) none of the a&o/e
Ans!er" D
#ection" $%3
0
Copyright ' 2(1$ )earson ducation* +nc,
13) 5i/e the num&er of asymmetric centers in limonene,
A) 2
B) 3
C) 1
D) -
) $
Ans!er" C
#ection" $%3
2() +dentify the compound6s) !ith asymmetric centers,
A)
B)
C)
D)
)
Ans!er" C
#ection" $%3
2
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21) A and B are stereoisomers, 7hey are nonsuperimposa&le and are mirror images of one
another, Which of the follo!ing &est descri&es the relationship &et!een A and B?
A) structural isomers
B) enantiomers
C) conformational isomers
D) diastereomers
) constitutional isomers
Ans!er" B
#ection" $%$
22) What is the relationship &et!een the structures sho!n &elo!?
A) enantiomers
B) diastereomers
C) configurational isomers
D) identical compounds
) constitutional isomers
Ans!er" D
#ection" $%$
3
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23) Which of the follo!ing compounds is an enantiomer of the structure &elo!?
A)
B)
C)
D) A and B
) +t does not ha/e an enantiomer,
Ans!er"
#ection" $%$
2$) Which of the follo!ing statements correctly descri&es the molecule sho!n &elo!?
A) +t is achiral,
B) +t is meso,
C) +ts asymmetric center possesses the R configuration,
D) 7he mirror image of this molecule is its enantiomer,
) 7he molecule possesses enantiotopic hydrogens,
Ans!er" D
#ection" $%$
1(
Copyright ' 2(1$ )earson ducation* +nc,
2-) Choose the enantiomer of the compound &elo!,
A)
B)
C)
D)
)
Ans!er"
#ection" $%$
2.) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" the same compound
#ection" $%$
11
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20) 7he compound CH
3
CHClCH
2
CH8CHCH
2
CH
3
contains only one asymmetric center,
1plain !hy it has four stereoisomers,
Ans!er" +n addition to the single asymmetric center !hich may &e either R or S* it also contains
a car&on%car&on dou&le &ond !hich may &e either E or Z, 7hus* the four stereoisomers can &e
designated E* R9 E* S9 Z* R9 and Z* S,
#ection" $%-
22) Dra! the enantiomer of the compound &elo!,
Ans!er"
#ection" $%.
23) +dentify the follo!ing compounds as R or S,
A) S, S, R
B) S, R, S
C) R, S, S
D) S, S, S
) R, R, R
Ans!er" D
#ection" $%.
12
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3() +dentify all pairs of enantiomers,
A) B and D* A and C
B) A and C
C) B and D
D) A and B* A and D* B and C* C and D
) B and D* A and B* A and D* B and C* C and D
Ans!er" C
#ection" $%.
31) +dentify all identical compounds,
A) B and D* A and C
B) A and C
C) B and D
D) A and B* A and D* B and C* C and D
) B and D* A and B* A and D* B and C* C and D
Ans!er" B
#ection" $%.
13
Copyright ' 2(1$ )earson ducation* +nc,
32) Which of the follo!ing compounds has an S configuration?
A)
B)
C)
D)
)
Ans!er" B
#ection" $%0
1$
Copyright ' 2(1$ )earson ducation* +nc,
33) Which of the follo!ing compounds has an R configuration?
A)
B)
C)
D)
)
Ans!er" A
#ection" $%0
3$) Which of the follo!ing groups has the highest priority using the Cahn* +ngold* )relog rules?
A)
B)
C) :OH
D) :O:CH
3
)
Ans!er" D
#ection" $%0
1-
Copyright ' 2(1$ )earson ducation* +nc,
3-) 7he configuration of R%6;)%glyceraldehyde is as follo!s"
What is the a&solute configuration of 6%)%lactic acid?
A) R configuration
B) L configuration
C) S configuration
D) R and S configuration
) D and L configuration
Ans!er" A
#ection" $%0
3.) +ndicate !hether each of the follo!ing structures has the R or S configuration, What is the
relationship &et!een the t!o structures?
Ans!er"
7herefore* the t!o compounds are enantiomers,
#ection" $%0
1.
Copyright ' 2(1$ )earson ducation* +nc,
30) <a&el each asymmetric center in the compound &elo! as R or S,
Ans!er"
#ection" $%0
32) Dra! the structure of 6S)%1%&romo%1%chloropropane, 7a=e particular care to indicate three%
dimensional stereochemistry detail properly,
Ans!er"
#ection" $%0
33) )ro/ide the structure of 6R)%$%octanol, Be careful to indicate proper stereochemistry,
Ans!er"
#ection" $%0
$() +dentify the follo!ing compounds as R or S,
A) R, S, R
B) S, R, R
C) S, S, S
D) R, R, R
) S, S, R
Ans!er" A
#ection" $%0
10
Copyright ' 2(1$ )earson ducation* +nc,
$1) )ro/ide a careful structure for 62R,3S)%2*3%di&romohe1ane,
Ans!er"
#ection" $%0
$2) )ro/ide a careful structure for 62S,3S)%2*3%di&romohe1ane,
Ans!er"
#ection" $%0
$3) )ro/ide a careful structure for 62S,3R)%2*3%di&romohe1ane,
Ans!er"
#ection" $%0
$$) <a&el each asymmetric center as > or #,
Ans!er"
#ection" $%0
12
Copyright ' 2(1$ )earson ducation* +nc,
$-) )ro/ide a careful structure for 62>*3#*$#)%2%&romo%$%methyl%3%he1anol,
Ans!er"
#ection" $%0
$.) )ro/ide a careful structure for 62S,3R,4R)%2%&romo%$%methyl%3%he1anol,
Ans!er"
#ection" $%0
$0) Which of the follo!ing is a true statement?
A) All chiral molecules possess a plane of symmetry,
B) All achiral molecules are meso,
C) All molecules !hich possess a single chirality center of the S configuration are le/orotatory,
D) A mi1ture of achiral compounds !ill &e optically inacti/e,
) All molecules !hich possess t!o or more chirality centers !ill &e chiral,
Ans!er" D
#ection" $%2
$2) Which of the follo!ing is not true of enantiomers?
A) 7hey ha/e the same melting point,
B) 7hey ha/e the same &oiling point,
C) 7hey ha/e the same chemical reacti/ity !ith non%chiral reagents,
D) 7hey ha/e the same density,
) 7hey ha/e the same specific rotation,
Ans!er"
#ection" $%3
13
Copyright ' 2(1$ )earson ducation* +nc,
$3) Which of the follo!ing is?are optically inacti/e?
A) a -(%-( mi1ture of R and S enantiomers
B) a meso compound
C) e/ery achiral compound
D) a racemic mi1ture
) all the a&o/e
Ans!er"
#ection" $%3
-() Which of the follo!ing statements correctly pertains to a pair of enantiomers?
A) 7hey rotate the plane of polari@ed light &y e1actly the same amount and in opposite
directions,
B) 7hey rotate the plane of polari@ed light &y differing amounts and in opposite directions,
C) 7hey rotate the plane of polari@ed light &y differing amounts and in the same direction,
D) 7hey ha/e different melting points,
) 7hey ha/e the same melting point* &ut they ha/e different &oiling points,
Ans!er" A
#ection" $%3
-1) +f 6S)%glyceraldehyde has a specific rotation of %2,0A* !hat is the specific rotation of 6R)%
glyceraldehyde?
A) %2,0A
B) ;2,0A
C) (,(A
D) cannot &e determined from the information gi/en
Ans!er" B
#ection" $%3
-2) A mi1ture of eBual amounts of t!o enantiomers CCCCCCCC,
A) is called a racemic mi1ture
B) is optically inacti/e
C) implies that the enantiomers are meso forms
D) &oth A and B
) none of the a&o/e
Ans!er" D
#ection" $%3
-3) A solution containing (,3. g of 2%&romooctane in 1( m< ether solution ga/e an o&ser/ed
rotation of %1,2A in a 1( cm cell at Calculate the specific rotation of this solution,
Ans!er" DEF 8
DEF 8 8 %12,0-A in ether
#ection" $%3
2(
Copyright ' 2(1$ )earson ducation* +nc,
-$) A ne!ly isolated natural product !as sho!n to &e optically acti/e, +f a solution of 2,( g in 1(
m< of ethanol in a -( cm tu&e gi/es a rotation of ;2,-0A* !hat is the specific rotation of this
natural product?
Ans!er" ;2,-0A
#ection" $%3
--) 7!enty grams of a compound !as dissol/ed in 1(( m< of sol/ent and ga/e an o&ser/ed
rotation of %2( degrees, 7he sample tu&e is $ dm long, Calculate the specific rotation,
Ans!er" %2-A
#ection" $%3
-.) 7he specific rotation of a pure su&stance is 1,.2A, What is the specific rotation of a mi1ture
containing 0-G of this isomer and 2-G of the 6%) isomer?
A) ;1,.2A
B) (A
C) ;1,2.A
D) ;(,2$A
) ;,($2A
Ans!er" D
#ection" $%1(
-0) 7he specific rotation of a pure su&stance is %-,3(A, What is the percentage of this isomer in a
mi1ture !ith an o&ser/ed specific rotation of %2,3-A?
A) 2-G
B) -(G
C) 0-G
D) 2(G
) (G
Ans!er" C
#ection" $%1(
-2) 6%)%Handelic acid has a specific rotation of %1-2A, What !ould &e the specific rotation of a
solution !hich contains $(G 6%)%mandelic acid and .(G 6;)%mandelic acid?
A) ;3-A
B) ;.3A
C) ;32A
D) %32A
) %.3A
Ans!er" C
#ection" $%1(
-3) 7he specific rotation of 6R)%6;)%glyceraldehyde is ;2,0A, +f a mi1ture of glyceraldehydes
enantiomers is 2(G S and 2(G R* !hat is the specific rotation of the mi1ture?
Ans!er" %-,2A
#ection" $%1(
21
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.() A sample of 6;) and 6%)%3%chlorohe1ane has a rotation of %2( degrees, )ure 6;) %3%
chlorohe1ane has a rotation of ;$( degrees, Calculate the enantiomeric e1cess and the amount
of 6%) and 6;)%3%chlorohe1ane in the original sample,
Ans!er" -(G* 0-G 6%)* 2-G 6;)
#ection" $%1(
.1) What is the relationship &et!een the follo!ing compounds?
A) superimposa&le !ithout &ond rotation
B) constitutional isomers
C) conformational isomers
D) diastereomers
) enantiomers
Ans!er"
#ection" $%11
.2) What is the relationship &et!een the structures sho!n &elo!?
A) enantiomers
B) diastereomers
C) configurational isomers
D) identical compounds
) constitutional isomers
Ans!er" B
#ection" $%11
22
Copyright ' 2(1$ )earson ducation* +nc,
.3) What is the relationship &et!een the follo!ing compounds?
A) enantiomers
B) diastereomers
C) constitutional isomers
D) conformational isomers
) identical compounds
Ans!er" A
#ection" $%11
.$) What is the relationship &et!een the follo!ing compounds?
A) enantiomers
B) diastereomers
C) constitutional isomers
D) conformational isomers
) identical compounds
Ans!er" B
#ection" $%11
.-) Which of the follo!ing is chiral?
A) cis%1%&romo%3%chlorocyclo&utane
B) trans%1%&romo%3%chlorocyclo&utane
C) cis%1*$%dimethylcyclohe1ane
D) cis%1*3%dimethylcyclohe1ane
) trans%1*3%dimethylcyclohe1ane
Ans!er"
#ection" $%11
23
Copyright ' 2(1$ )earson ducation* +nc,
..) Ho! many diastereomers e1ist for the compound &elo!?
A) 2
B) $
C) .
D) 0
) 2
Ans!er" C
#ection" $%11
.0) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" enantiomers
#ection" $%11
.2) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" diastereomers
#ection" $%11
2$
Copyright ' 2(1$ )earson ducation* +nc,
.3) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" diastereomers
#ection" $%11
0() Dra! the structure of 62R*3S)%dichloropentane, 7a=e particular care to indicate three%
dimensional stereochemistry detail properly,
Ans!er"
#ection" $%11
01) Dra! the structure of 62S*3R)%dichloropentane, 7a=e particular care to indicate three%
dimensional stereochemistry detail properly,
Ans!er"
#ection" $%11
02) Dra! the structure of any diastereomer of 62R*3S)%dichloropentane, 7a=e particular care to
indicate three%dimensional stereochemistry detail properly,
Ans!er"
#ection" $%11
03) #teroisomers !hich are not mirror image isomers are CCCCCCCC,
Ans!er" diastereomers
#ection" $%11
2-
Copyright ' 2(1$ )earson ducation* +nc,
0$) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" the same compound
#ection" $%11
0-) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" the same compound
#ection" $%11
0.) Which of the follo!ing terms &est descri&es the pair of compounds sho!n" enantiomers*
diastereomers* or the same compound?
Ans!er" enantiomers
#ection" $%11
00) Dra! the stereoisomers of 1*3%dichlorocyclopentane,
Ans!er"
#ection" $%11
2.
Copyright ' 2(1$ )earson ducation* +nc,
02) )ro/ide a perspecti/e dra!ing of 62R*3S)%1*2*3%trichloropentane,
Ans!er"
#ection" $%11
03) )ro/ide a perspecti/e dra!ing of the enantiomer of 62R*3S)%1*2*3%trichloropentane,
Ans!er"
#ection" $%11
2() )ro/ide a perspecti/e dra!ing of each diastereomer of 62R*3S)%1*2*3%trichloropentane,
Ans!er"
#ection" $%11
21) +dentify all pairs of diastereomers,
A) B and D* A and C
B) A and C
C) B and D
D) A and B* A and D* B and C* C and D
) B and D* A and B* A and D* B and C* C and D
Ans!er" D
#ection" $%11
20
Copyright ' 2(1$ )earson ducation* +nc,
22) +dentify all meso compounds,
A) B and D* A and C
B) A and C
C) B and D
D) A and B* A and D* B and C* C and D
) B and D* A and B* A and D* B and C* C and D
Ans!er" B
#ection" $%11
23) +dentify all configurational isomers,
A) B and D* A and C
B) A and C
C) B and D
D) A and B* A and D* B and C* C and D
) B and D* A and B* A and D* B and C* C and D
Ans!er"
#ection" $%11
22
Copyright ' 2(1$ )earson ducation* +nc,
2$) Which of the follo!ing is a meso compound?
A)
B)
C)
D)
)
Ans!er" A
#ection" $%13
23
Copyright ' 2(1$ )earson ducation* +nc,
2-) What is the relationship &et!een the follo!ing compounds?
A) enantiomers
B) diastereomers
C) constitutional isomers
D) conformational isomers
) identical compounds
Ans!er"
#ection" $%13
2.) Which of the follo!ing is a meso compound?
A) trans%1* $%dimethylcyclohe1ane
B) cis%1* 3%dimethylcyclohe1ane
C) trans%1* 3%dimethylcyclohe1ane
D) cis%1* $%dimethylcyclohe1ane
) trans%1* 2%dimethylcyclohe1ane
Ans!er" B
#ection" $%13
20) Ho! many stereoisomers e1ist !ith the follo!ing &asic connecti/ity?
BrCH
2
CH6CH
3
)CH
2
CH
3
A) (
B) 1
C) 2
D) $
) 2
Ans!er" C
#ection" $%13
22) Ho! many stereoisomers e1ist !ith the follo!ing &asic connecti/ity?
CH
3
CHClCH
2
CHClCH
3
A) (
B) 1
C) 2
D) 3
) $
Ans!er" D
#ection" $%13
3(
Copyright ' 2(1$ )earson ducation* +nc,
23) Which of the statements &elo! correctly descri&es an achiral molecule?
A) 7he molecule has a nonsuperimposa&le mirror image,
B) 7he molecule e1hi&its optical acti/ity !hen it interacts !ith plane%polari@ed light,
C) 7he molecule has an enantiomer,
D) 7he molecule might &e a meso form,
) none of the a&o/e
Ans!er" D
#ection" $%13
3() Consider the molecules !ith molecular formula C
2
H
2
Br
2
Cl
2
,
a) Dra! a structure that is optically inacti/e &ecause it does not ha/e an asymmetric center,
&) Dra! a structure that is optically inacti/e &ecause it is a meso compound,
c) Dra! a structure that is optically acti/e &ecause it is chiral,
Ans!er"
a)
no chirality center
&)
meso compound
c)
chiral
#ection" $%13
31
Copyright ' 2(1$ )earson ducation* +nc,
31) Dra! the structure of a meso form of 1*3%dichlorocyclopentane, 7a=e particular care to
indicate three%dimensional stereochemistry detail properly,
Ans!er"
#ection" $%13
32) <a&el the molecule sho!n as chiral or achiral,
Ans!er" Achiral
#ection" $%13
33) <a&el the molecule sho!n as chiral or achiral,
Ans!er" Chiral
#ection" $%13
3$) <a&el the molecule sho!n as chiral or achiral,
Ans!er" Achiral
#ection" $%13
32
Copyright ' 2(1$ )earson ducation* +nc,
3-) <a&el the molecule sho!n as chiral or achiral,
Ans!er" Chiral
#ection" $%13
3.) +s the molecule sho!n chiral? +s it a meso compound?
Ans!er" not chiral9 not meso
#ection" $%13
30) +s the molecule sho!n chiral? +s it a meso compound?
Ans!er" not chiral9 not meso
#ection" $%13
32) +s the molecule sho!n chiral? +s it a meso compound?
Ans!er" not chiral* meso
#ection" $%13
33
Copyright ' 2(1$ )earson ducation* +nc,
33) +s the molecule sho!n chiral? +s it a meso compound?
Ans!er" not chiral9 not meso
#ection" $%13
1(() What is the configuration of the follo!ing compound?
A) 2S* 3R
B) 3R* 3S
C) 2S* 3S
D) 2R* 3R
) CanIt do R and S9 the compound is achiral,
Ans!er" C
#ection" $%1$
3$
Copyright ' 2(1$ )earson ducation* +nc,
1(1) +n the Jischer proKection &elo!* !hat are the configurations of the t!o asymmetric centers?
A) 2R* 3R
B) 2R* 3S
C) 2S* 3R
D) 2S* 3S
) cannot &e determined from structure
Ans!er" A
#ection" $%1$
1(2) <a&el each asymmetrical car&on in the compound &elo! as R or S,
Ans!er"
#ection" $%1$
3-
Copyright ' 2(1$ )earson ducation* +nc,
1(3) Dra! a perspecti/e formula of 62R*3S)%3%&romo%2%&utanol,
Ans!er"
#ection" $%1$
1($) Dra! any diastereomer of 62R*3R)%2*3%dichloropentane, Be careful to indicate proper
stereochemistry,
Ans!er"
#ection" $%1$
1(-) Can one predict !hether a compound !ith a single asymmetric center is de1tro% or
le/orotatory &ased on the R/S assignment at this asymmetric center? 1plain &riefly,
Ans!er" Lo, R/S assignment is purely a con/ention of nomenclature and is completely
independent of the direction in !hich plane%polari@ed light is rotated &y the compound,
#ection" $%1$
1(.) Assign an R or S configurational la&el to each asymmetric center in the molecule &elo!,
Ans!er"
#ection" $%1$
3.
Copyright ' 2(1$ )earson ducation* +nc,
1(0) 5i/e the complete name6s) of the follo!ing compound,
Ans!er" 62R, 4S)%2*$%dichloropentane or 62S, 4R)%2*$%dichloropentane
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1(2) Briefly descri&e ho! t!o enantiomers might &e separated,
Ans!er" 7he t!o compounds can &e con/erted to diastereomers* separated &ased on different
physical properties of these diastereomers* and su&seBuently returned to their original forms or
chromatographic separation using a chiral stationary phase,
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1(3) 7he compound &elo! contains an asymmetric center at nitrogen, Why canIt indi/idual
stereoisomers of this compound &e isolated at room temperature?
Ans!er" Litrogen has a pair of non&onding electrons that allo! it to turn Minside outM at room
temperature, Because of rapid in/ersion* the indi/idual stereoisomers cannot &e isolated,
#ection" $%1.
11() +dentify the compounds that ha/e an asymmetric center,
A) A
B) B
C) C
D) A and B
) A* B* and C
Ans!er"
#ection" $%1.
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Copyright ' 2(1$ )earson ducation* +nc,
111) +dentify the pair of compounds,
A) identical
B) conformational isomers
C) constitutional isomers
D) configurational isomers
) none of the a&o/e
Ans!er" C
#ection" $%32
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Copyright ' 2(1$ )earson ducation* +nc,
