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Conquer (kIli)

CHEMISTRY
Isomerism

Practice Booklet
 6. 5 3. 2. 1.
7
3

Position
Functional
isomer
(4) isomer HOCH,-CH;CHO
CH,CH;COOH
HCO0C,Hs (2) (1) iSomers
(1) Possible isomers
(4) isomers
1 are Functional (3Chain
) Position
isomers
(2) (1) position
(1) Which
(4) (3) (2)isomers: Ring-chain isomers
)Position
isomers(41-Chlorobutane
) isomers
(3Chain
(2) (1)
(3) isomer
(Chain
2) (1) (4) (3) Functional (4) (3) (2) Which
(1) the of
Metamers Both Propanoic
Propionaldehyde Ethanol
Methanol Ring CH:(OH)CH;C0,H
(C,H);CO
CH,CH;0CH,CH;CH3
(C,H):CO
All & Geometrical
isomers
&n are: the Structural
Isomerism
chain of
(1) number
group and (2) 2 above the
& &
(2) isomers:are
acid andfollowing isomers
ethoxyethane CH,OCH3 following &
of 2-Chlorobutane
isomer
methoxymethane
and disubstituted are &
and (3) 3
ethylacetate called CH,CH(OH)CO,H
of
acetone pairs
CH,CO0CH3
is
(4) 4 : are are:
benzene
called
is:
Exercise-I

14 13. 12. 11. 10. 8.

(1CeHhs: isomers
(4) (3) Position
Metamers
) 5 for HowGeometrical isomers
(2) (1) compounds
H Given
are: 3 to
(3) 2 (1) present The isomerism
(3) 5 (1)chain
2are:
present isomers
TheGeometricalisomers
(3) isomers
(4) Position (2)Chain(1)
Propene (4) (3) (2) (1) The Metamer(4) isomer isomer
(3Chain(2) (1)
) Position
CH,CONH,
Functional
isomers
group -C-NH shoW Both Only Only Only Functional
isomer
many minimum
Ring formula
minimum
position in in chain andcarboxylic an an an
(2) 4 - an &
structural an carboxylic
alcohol ester CHeO;
CH2 organ1C cyclopropane HCONHCH,
number organic
number
isomers
- isomerism
(3) 3 Br (4) 5 (2) 4 (4) 4 (2) 3 acid represents:
isomers & Compound acid
Br of
compound of and are
are: called:
C-- are: carbon carbon ester
(4) 2 are
Isomerism NH to
possible be to
- atoms
CH3 able showatoms

19 18. 17. 16. 15.

Isomerism

(4 (3 (2) (1) Whichthe of (4)Homologues

isomers
are Functional isomers
Chain
(4) Functional
isomers
Position(3) isomers
Metamers (2) (1) isomers
(3Chain
) (1) and compounds
Given
are:
isomers
(3)Chain(2) (1) MenMe CH,0:
)3
(1possible How
functional None Position
a-owOocn many
OH of
OH
and these (2) with
and and and isomers benzenoid
following
group 4
and -0-CH,-CH:-CI
MeeH the
isomers? Metamers
(4) (2) (3)
Me
pairs Ring molecular
2isomeric
are:
of chain
compounds (4) 5 phenols
isomers Formula

are

25. 24 23 22 21. 20.

3) isomerism:
(2) (1)showWhich
(4) (geometrical CH;(4) C,H(3BrC;H:N 1) matchis: Trans(3)
,) , (2) C.He(Incorrect (1) E Configuration (1simplest
)2
hydroxylamine: Number
the None(4) (3) (2) (1) () Which (4) isomers CH3
Position
isomers (3) Chain(2) (1)
H,C M.F. other Metamers Functional
CH, CH, (CH),C simplest |& l
I Br Geometrical
Isomerism -
has is CH;
- - = of Il has
CBr; of are incorrect
CHCH = (2) 4 E Z () -CHO
CH the unsymmetrical
ketone oximes configuration
configuration
= of symmetrical geometrical
CCL, = CH isomers
No.of group
-
following the &
C,H, statement:
- 3 3 3 (4) formed CH,
CH, (2) Z given (3) 3 isomers
alkenes
2 =
& isomers CH
compound 3 molecule ketone on -
both
(4) 1 CH,OH
reaction of
of
is: and each
are:
4 can with the
 26. Which of the following is not true 33. Geometrical isomerism is shown by Which of the following compound is Stereo isomers but not mirror images are
regarding hex-2-ene: 39
called:
(1) Boiling point of cis is higher (1) (2) achiral:
B (1) Enantiomers
(2) Trans isomer has zero dipole moment
(2) Mesomers
(3) Trans is more stable than cis (1) (2)
(4) Can show position
(3) Tautomers
isomerism (3) (4)
(4) Diastereomers
27. Which of the following compounds will 45, The number of optically active isomers
show geometrical isomerism: 34. Among the following compounds, the one possible in are:
which can exhibit geometrical (3) (4)
(1) 2-Butene
(2) 1-Chloro-1-butene is:
isomerism CH;-ÇH-CH-CH-CH,-OH
(1) 1,3-Butadiene (2) 1,2-Butadiene OH OH OH
(3) 1-Phenylpropene
(3) 1,3-Pentadiene (4) 1,4-Pentadiene Which of the following statement is true (1) 2 (2) 4 (3) 6 (4) 8
(4) All of above 40

35. Which of the for the given compound:

28 following has 46 Which of the following contain chiral
Which is a pair of geomnetrical isomers: Me OH
configuration: carbon atom:
Ch Ch
HC, Br CH(CH,),
Br
cH.
(1
H
(2) C=C H Me () CH,-ÇH-CH-CH,-CH,
CH, HOCH, CH,-CH, HO OH
(3)
C (1) Optically active
Rr (4) All the above (2) CH,-ÇH-ÇH-CH,
(2) Has plane of symmetry Br H3
(1) Iand I (2) | and I||
(3) I| and IV (3) Has centre of symmertry
(4) I and IV
(4) 1&3 both (3) CH,-CH-CH-CH,
Optical lsomerism Br
29. But-2-ene exhibits cis-trans isomerism 36 Which of the following can show 41. How many stereoisomers are possible for (4) All the above
due to: optical
(1) Rotation around C3-C4 isomerism: the given compound:
sigma bond (1) 1-Chlorobutane Which of the following can have meso
(2) Restricted rotation around C=C (2) t-Butyl chloride
bond (3) sec-Butyl chloride isomer:
(3) Rotation around C-C, bond (4) Isobutyl chloride
(1) 3-chloro-2,4-dimethylpentane
(4) Rotation around C-C3
double bond 37. Which of the following (1) 2 (2) 4 (3) 3 (4) 8 (2) Pentane-2,3-diol
compound can
(3) Cyclopentane-1,2-diamine
30 have meso isomer: Absolute configuration of the given
The number of
geometrical isomers of (1) Butane-2,3-diol compound is: (4) 2-Chlorobutane
CH;CH=CHCH=CH-CH=CHCL are: (2) 2,3,4-Trichloropentane ÇHO
(1) 2 (2) 4 (3) 6 (4) 8 48 Number of optically active isomers of
(3) 2,3-Dichlorobutane HO
31. Which of the following (4) All tartaric acid is CH(OH)COOH
functional group H,OH CHOH)CoOH
containing Compounds can exhibit 38 Which of the following
compound can (1) L (2) D (3) S (4) 1&3 both
geometrical isomerism: show optical isomerism: (1) 2 (2) 3 (3) 4 (4) 5
(1) > C = C<
(2) > C = N - 43. How many asymmetric carbon atoms are
(3) - N = N - 49. Meso form of tartaric acid is :
(4) All of these present in :
Me (1) Dextorotatory
(1) Me
32. (2) ()1, 2-Dimethylcyclohexane
CH, -C-CI has the H (2) Laevorotatory
configuration: (ii) 3-Methylcyclopentene (3) Neither Laevo nor dextro rotatory due
c-l-Br
(1) Trans (2) Z c^Br
(ii) 3-Methylcyclohexene
(1) Two, one, one (2) One, one, one
to internal compensation it will be
optically inactive
(3) E (3) (4) All
(4) Both (1) &(2) (3) Two, none, two (4) Two, none, one (4) A mixture of equal quantities of dextro
HBr
and leavo rotatory forms

Isomerism Isomerism 6
 54. Which of the followin8 pair represents Exercise - I|
50 The process of separation of race mic
diastereomers? the
mixture into d and l enantiomer is called:
6. What is the relationship between
CH3 CH3 Assign double bond configurations to the molecules in the following pairs?
(1) Resolution 1.
(1) H Br H -Br
(2) Dehydration following: CHO CH OH
-OH & HO -H COOH
H H
(3) Revolution H OH HO
CH: CH3 OH
NO OR
(4) Dehydrohalogenation COOH COOH CH,OH HO
and HO H
OH HO
51. Which compound would exhibit optical HO -H
(2) H CN CHOH CHO
isomers:
HO
H,N-H,C
HO (2) Diastereomers
COOH ON (1) E, Z (2) Z, E (1) Enantiomers
COOH OOH
(3) E, E (4) Z, Z (3) Identical (4) Structural isomers
(1) CaHs
NO HO0c HO - CH,- CH; - F
What are the correct designations for the
CzHs -0H Which conformer of above compound is
7.
CH (3) H - o structure below?
& H -OH CH3
most stable across C- C?
(2 -OH HC H -oH CH3
Anti staggered (2) Partially eclipsed
HO
COOH CH COH
(3) Gauche (4) Fully eclipsed
HOOCH (4) All of these 3. The geometrical isomerism is shown by: (1) E, E
(3) Conformational IsomerismN (2) Z, E
COOH (2) (3) E, Z
55. Isomers which can be interconverted (4) Geometrical isomerism not possible.
through rotation around a single bond are: 8. Which one of the following is a diastereomer
CHCI
(1) Conformers (4 of (R)-4-Bromo-cis-2-hexene?
(4)
(1) (S) -4-Brom0-cis-2-hexene
(2) Diastereomers
52 Which of the following starred 'C' -atoms (2) (R)-4-Bromo-trans-2-hexene
(3) Enantiomers 4. The following pair of compounds is best
is chiral: (3) (S) -4-Bromo-trans-2-hexene
(4) Positional isomers described as : (4) 2 & 3 both
(1) CH,CH, H (CH)CH,0H 56. How many conformations does ethane Which of the following is the least stable
have: conformer of cyclohexane?
(2) CH.CH,CH(H,)CH,0H (1) 1 (2) 2 (3) 3 (4) Infinite
57.
(1) ldentical
(3) CH, CH, CH(CH)CH,OH The eclipsed and staggered conformation (1) (2)
of ethane is due to: (2) Diastereomers (Chair) (Boat)

(3) Enantiomers
(4)CH,CH,CH(CH) H, OH (1) Free rotation about C-C single bond
(4) Constitutional isomers
53. Which of the following structures (2) Restricted rotation about C-C single
5. Which the following compounds is/are (3) (4)
represents a threo-stereoisomer: bond meso forms?
g-lu:oM
(Twis! Doal) (Half-chat
CH
ÇH (3) Absence of rotation about C-C bond CH
H H
CH. 10. Which of the following depict the same?
-Br ÇH.
CH
(1) H OH (2) HBr (4) None of the above H H
CH CH.
CH CH 58 Dihedral angle require to get maximum H C -H

CH B CH CH C
CH stable conformer from minimum stable CH,CH, CH CH
Br- -H
(1) (2) (3)
(3) H-er " HO conformer in C,-C% bond of n-butane is:
CH
CH CH R
(1) 360 (2) 180° (3) 120 (4) 240° (1) 1only (2) 3 only 2
(3) 1 and 2 (4) 2 and 3

7
Isomerism Isomerism
 (2) CH-ÇH-CH=FCH-CH-CH.
CH CH, 19. Which of the following pairs of compounds Polarimeter tube
CH, are not positional isomers?
25.
HC B (3) CH, -CH= CH-CH, HO CH,
OH

(4) CH, - CH, -CH=CH-CH, -CH, (1) and P.P.L.

Soln. of compound
C
16 For geometric isomers of 3-hexene: Which of the following statement can be
3 C.H, H CH,
H
true for the compound filled in
(1) 1and 2 (2) 1and 3
(2 and
(3) 2 and 3 (4) 1, 2 and 3 C=c CH polarimeter tube:
OH OH
11 (1) Compound does not show optical
The total number of stereoisomer possible CH C.H CH,OH OCH,
for 2,3-Dichlorobutane: C.H (3 and isomerism.
(1) 2 (2) 3 (3) 4 (4) 5 (1) M.P. is high and dipole moment high (2) Compound is an optical isomer but is
12. Which of the following structure iis not for trans
(4) All of these optically inactive.
(2) M.P, is low and dipole moment low for
meso-2,3-butanediol?
trans
20. CH-CH=¢- =CH-CH, (3) Solution is equimolecular mixture of d
CH. OH

-OH
(3) M.P, is high and dipole moment low for Br Br and lmirror images compounds.
(1) CH trans How many geometrical isomers are (4) All
-CH H CH (4) M.P, is low and dipole moment high for possible for the above compound:
OH trans (1) 2 (2) 3 (3) 4 (4) 6
17. In which of the following CH,-CH=(-Ç==CH-CH, Which of the following will form only one
CH compound. 21. 26
oxime on reaction with NH,OH solution.
posses plane of symmetry as well as
(3) OH CH
(4) centre of symmetry? How many geometrical isomers are
H -HO
possible for this compound?
OH CH, (1) 2 (2) 3 (3) 4 (4) 6
13 Which of the following is a meso (1) (2
22
compound?
CH, =CH-CH =CH- CH=CH,
How many geometrical isomers are (U) ()
CH, CH-CH,
possible for this compound
-8r -OH CH
H -Br (2) CH, (1) 2 (2) 3 (3) 4 (4) 8 CI
OH
(3) (4) 23 Which of the following compound can
CH
CH-CH, show geometrical isomerism?
(3) (4) All of these CH CH CH,
18. The pair of (I) (IV
enantiomers among the (1)
OH OH CH, (1) I, I| (2) I, u
14
following compound is:
Among the following which one can have a CH, (3) I, IV (4) I1, , IV
CH, CH,
meso form (3) (4)
Ph EL 27 Which can not be the diastereomer (i.e.
(1) CH,CH(OH)CH(CI)C,H, Br
24 Which is correct structure of non mirror iimage stereoisomers) of the
(2) CH,CH(OH)CH(OH)CH, B Ph D-glyceraldehyde?
(0) following compound.
(3) C,H,CH(OH)CH(OH)CH, CHO
CH,

15.
(4) HOCH,CH(CI)CH,
Which of the following will not
show
Ph
Br Rr.
-CH,
(1) H
+
CH,OH
-OH (2) HO -CHO

CHOH
CHO.C(CH,) = C(CH)CHO?

(1) c= (2) c ~CHO

geometrical isomerism? Ph CH,OH
(1) CHC=CH-CH-CH, (1) (IV)
(1) |and IV
(3) HO (4) All of these
CH, (2) land IV (3 CH (4) All of these
(3) I| and ||| CHO OHCZC CHO
(4) Iand I|

Isomerism Isomerism 10
 (8) A meso compound has
Which of the following is correct set of no
28. centres and thus
are chiral NH, 36. Correct configuration of the following is:
physical properties of the geometrical
isomers?
(C)
inactive.
A meso CompOund has
opticaly (3) H -CO,H (4) H.N
CH,OH

-H
CH,
H -OH
QH
which are
mirror images superimposable molon ecules CH OH
H C=C Br
even though tthey
contain chiral centres,
heir CH,OH
CO,H
(U) () 34. Which of the following pairs can be resolved? (1) 2S, 3s
(D) Ameso compound is
because the rotation optically
R

Dipole
moment| point
Boiling Melingst bility
point molecule is cancelled caused by
by an
inactivanye (A
R
R
(2) 2S, 3R
(3) 2R, 3S
opposite rotation equal and
(1)| |> | |<|| ||> | |>|| causedmirrorby another
molecule that is the Ri
R
(4) 2R, 3R

(2) >| I|>| I|>|

I|>| the first. image of OH OH
Find the number of stereo isomers of
(1) A and B (2) B and C 37.
(3) |> I| I>l|
(3) C and D (4) Aand C
(B) 1,2-dihydroxy cyclopentane:
(4) D>| I|>| HOOC COOH (1) 1 (2) 2 (3) 3 (4) 4
29 Which of the following is optically inactive CH, CH.
32. Which of the following operations on the Which of the following is optically active:
CH. 38
HO CH HO: CH CH, OH
(1) (2) HO
H,C -OH Fischer formula H -OH does not OH
H H
C,H, (1) (2 CH,
HO
CH. OH change its absolute configuration? NO, NO, NO, NO,
(3) HO (4) H,CH (1) Exchanging groups across the ÖH
H.
H,COH
horizontal bond
30. Which of the following will not show (D) OH CH,
(2) Exchanging groups across the vertical
optical isomerism?
(1) Cl - CH = C =C = CH - Cl bond (4)
(1) A, B and C (2) A and C
(3) Exchanging groups across the
(2) Cl - CH = C =C = C = CH -Cl (3) B and D (4) B, C and D
horizontal bond and also across the 35. Which is a pair of geometrical isomers: 39. Which of the following are not enantiomer
ÇOOH vertical bond Me pair.
(3) H -OH (1) and
H -OH (4) Exchanging a vertical and horizontal Br CI Me C,H, CH, C,H, Cl
COOH group
33. Among the following L-serine is Ph OH
H C Me (A)
CH
ÇOOH (2) and (B)
Me Ph
C=N
OH
(1) H,N - -CH.OH C,H, C,H. CH,
(4)
H Me Ph
Me (3) and CI
M
CO,H
Me Me Me (C) (D)
31. Which of the following (2) HOH,C
correct ?
statements is/are -H (1) A and C (2) A and D
(A) A (3) B and C (4) Cand D
meso compound has chiral centres (4) and
NH
and show optical
isomerism

11

Isomerism Isomerism 12
 Dxercise-I
(Previous Years Question) 10 Which of the following acids does not 14. In which of the following molecules, all
exhibit optical isomerism? atoms are coplanar? (NEET-2016]
Which of the
1. The configuration of the given compound 6 following compounds wi [AIPMT PRE-2012]
exhibit cis-trans (geometetrical) isomerism ? (1) Lactic acid
(AIPMT-2005]
(1) 1-Butanol
(3) 2-Butanol
[AIPMT-2009)
(2) 2-Butene
(4) 2-Butyne
(2) Tartaric acid
(3) Maleic acid
CN
the following the most stable (4) a-amino acids
(3) ( (4) CHCH CN
conformation of n-butane is : Two possible stereo-structures of
11. is
(1) E Which of the following biphenys
2 Which
(2) R

one of the following

(3) S (4) Z

pairs
CH
[AIPMT-CH,2010)
CH, CH,CHOH.COOH,
active, are called
which are

[AIPMT PRE-2015]
optically
15.
optically active ?
0,N
[NEET-I

represents stereo isomerism (1) (2 (1) Enantiomers (2) Mesomers

[AIPMT-2005] (1)
HcH (3) Diastereomers (4) Atropisomers
(1) Linkage isomerism and Geometrical
ISomerism CH,
(2) Chain isomerism and Rotational CH.
12. The number of structural isojmers possible
CH Br
isomerism from the molecular formula CzH,N is :
(3) Optical isomerism and Geometrical (3 (4)
ISomerism [AIPMT PRE-2015]
(2)
(4) Structural isomerism and Geometrical (1) 2 (2) 3
isomerism 8. Which of the following conformers for
(3) 4 (4) 5
ethylene glycol is most stable :
3. Which of the following is not chiral : 13. The correct corresponding order names of
OH
[AIPMT-2010]
[AIPMT-2006] JOH
OH four aldoses with configuration given
(1) 2-Butanol (NEET-2016] (3)
below
(2) 2.3-Dibromo pentane (1 (2) HO
CHO CHO
(3) 3-Bromo pentane H H H OF HÌ H

(4) 2-Hydroxy propanoic acid OH -OH

HOH CH
H OH H,OH H,OH
CH-CHCICH,-CH, has a chiral centre H
which one of the following represents its R (3) H (4)
AH CHO CHO
configuration : (AIPMT-2007] -OH
H HO H
CH,
ÇH, CH. 9. The IUPAC name of the following compound HOH HO H
The correct statemnent regarding the
CH OH
(2) CicH, H,OH 16.
comparison of staggered and eclipsed
C
CI CH,CH3 respectively, is:
conformation of ethane, is:
is:
(1) D-erythrose, D-threose, L-erythrose, (NEET- 2016]
CH CH3
CH. L-threose (1) The staggered conformation of ethane
(4) HC [AIPMT MAINS-2011)] (2) L-erythrose, L-threose, L-erythrose,
less stable than eclipsed

CH conformation, because staggered

(1) cis-2-chloro-3-iodo-2-pentene D-threose conformation has torsional strain
5. How many stereoisomer (2) trans-2-chloro-3-iodo-2-pentene (3) D-threose, D-erythrose, L-threose, (2)
The eclipsed conformation of ethane
does this
molecule have CH,CH=CHCH,CHBrCH, more stable than staggered
(3) cis-3-iodo-4 -chloro-3-pentene L-erythrose S

D-erythrose, conformation, because eclipsed

[AIPMT-2008] (4) trans-3-iodo-4-chloro-3-pentene (4) L-erythrose, L-threose, conformation has no torsional strain
(1) 8 (2) 2 (3) 4 (4) 6
D-threose

13 14

Isomerism Isomerism
 Both bond angle and
(3) The eclipsed conformation of ethane
(3)
change
bond length EXERCISE I
is more stable than staggered
(4) Both bond angles and
conformation even through the
remains same bond length Oue. 1 2 3 4 5678
ANSWER KEY
ecipsed conformation has torsional 10 1112 13 14 15 16 17 18 19 20 1 22 23 24 25
1 1 1 3 4 42 4 4 43
strain Ans. 4 1 21 4 34
(4) The staggered conformation of ethane
18. Dihedral angle of least stable conformer of Que. 26 27 28 29 30 31 32 34 35 36 37 38 39 41 42 43
2

44 45 46 47 48
1

49
is more
conformation.
stable than eclipsed
because staggered
ethane is :

(1) 120°
(NEET(UG) 2021]
(2) 180
|Ans.

lQue.
2 4 3
52 53
2

54
4

Ss
4
56
4
57 58
2 3 4 3 1 23 1 4 4 3 1 3 1

conformation has no torsional strain. Ans. 1 13 4 4

4 12
17.
(3) 60° (4) 0°
With respect to the conformers of ethane.
which of the following statements is true? The compound which shows EXERCISE I
19. metamerie ANSWVER KEY
(NEET-2017]
(1) Bond angle remains same but bond
is
[NEET(UG) 2021])
(2) CaHaO
Que. 1 4 5 6 7 8 10 11 12 13 14 15 16 17 18 19 20 21
3 3 |2 3 1 | 4 4 | 4
22 23 24 25
length changes (1) CsHi2 lAns. 4 4 4 4 1 4 2 1 3 4
loue. 26 27 28 2930
(2) Bond angle changes but bond length (3) C,H,o (4) CaHoO 3 3 33 34 35 36 37 38 39
remains same Ans. 2 13 3 1 4 3 3 3 |3 1 3 2 1

EXERCISE II
ANSWER KEY
lQue. 1 2 34s 6 89 10 11 12 13 14 15 16 17 1s 19
Ans. 2 3 323 2 3 13 2 2 |4 4 4

15

16
Isomerism
Isomerism