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Information about organic chemistry, including the synthesis of the first organic compound, the number of optical isomers, stereochemistry, free radicals, and hybridization. It also includes questions related to bonding and hybridization in organic compounds. a comprehensive overview of organic chemistry concepts and is useful for students studying this subject.
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urea in the laboratory.
depends on its structure and number of asymmetric
carbon atoms present in its molecule.
other are called diastereomers.
atoms using sequence rules is
involve free radicals.
when hydrogen is replaced by a halogen. It is
catalysed by benzoyl peroxide ( C 6
5
2
addition reaction.
than n - propyl free radical ( CH 3
2
2
basis of hyperconjugation or conjugation.
electrophilic addition reaction due to the formation
of more stable 2° carbocation.
1
is 3°>
2°>1°>methyl while SN
2
is methyl > 1°> 2°> 3°.
1
while non polar
solvents favour SN
2
reactions.
CH 2 Cl 2. This is because in CH 2 Cl 2 all bond moments
reinforce each other while in CHCl 3
the bond moment
of one of the Cl opposes the net moment of the other
two.
1
while high concentration favour SN
2
1
the attack of the nucleophile may be from
either side and so recimization takes place. However,
in SN
2
the attack of the nucleophile takes place from
back side. So it leads to inversion of configuration.
mechanism.
allyl chloride and the intermediate is allyl free
radical.
1. In methane molecule, the hydrogen atoms around
carbon are arranged as [DPMT 1980; MNR 1981; MP PET 1997, 99]
(a) Square planar (b) Tetrahedral
(c) Triangular (d) Octahedral
2. In carbon tetrachloride, four valence of carbon
are directed to four corners of [CPMT 1973, 77]
(a) Rectangle (b) Square
(c) Tetrahedron (d) None of these
3. In alkene (ethene) number of
2
sp
hybrid carbon
atoms are
(a) 1 (b) 2
(c) 3 (d) 0
4. Each carbon atom in benzene is in the state of
hybridization
[CPMT 1973, 83, 89; MP PMT 1993;
KCET (Med.) 1999; DCE 2001]
(a)
3
sp (b)
2
sp
(c) sp (d) s p
3
5. Which of the following hybridisation has highest
percentage of s- character [BHU 1986]
(a)
3
sp (b)
2
sp
(c) sp
(d) None of these
6. The hybridisation present in
2 2
CH is [EAMCET 1993]
(a) sp (b)
2
sp
(c)
3
sp (d)
2
dsp
7. What hybrid orbitals will form the following
compound
3 2 3
(a) sp and
3
sp (b)
2
sp and
3
sp
(c) sp and
2
sp (d) Only
3
sp
8. The compound in which carbon uses only its
3
sp
hybrid orbitals for bond formation is [IIT-JEE 1989]
(a) HCOOH (b) NH CO
2 2
(c) CH COH
3 3
( ) (d) CH CHO
3 3
9. A straight chain hydrocarbon has the molecular
formula
8 10
CH. The hybridisation for the carbon
atoms from one end of the chain to the other are
respectively sp , sp , sp , sp , sp , sp , sp
3 2 2 3 2 2
and sp
The structural formula of the hydrocarbon would
be [CBSE PMT 1992]
(a)
3 2 2
(b)
3 2 2 2
(c)
3 2 2
(d) CH CH CH CH CH CH C CH
3 2
10. Which of the following has a bond formed by
overlap of
3
sp sp hybrid orbitals [MNR 1993; UPSEAT 2001, 02]
(a) CH C C H
3
(b)
3 3
(c)
2 2
(d) HC CH
11. The bond between carbon atom (1) and carbon
atom (2) in compound
2
N C CH CH involves
the hybridised carbon as [IIT-JEE 1987; DCE 2000]
(a)
2
sp and
2
sp (b)
3
sp and sp
(c) sp and
2
sp (d) sp and sp
12. Number of bonds in
2
is
[Kurukshetra CEE 1991; KCET 2000]
(a) 2 (b) 3
(c) 4 (d) 5
13. Number of electrons present in naphthalene is
[AFMC 1991]
(a) 4 (b) 6
(c) 10 (d) 14
14. Number of electrons in cyclobutadienyl anion
2
4 4
( )
C H is [IIT-JEE 1991]
(a) 2 (b) 4
(c) 6 (d) 8
15. Homolytic fission of C - C bond in ethane gives an
intermediate in which carbon is [IIT-JEE 1992]
(a)
3
sp hybridised (b)
2
sp hybridised
(c) sp hybridised (d) sp d
2
hybridised
16. In the reaction
4
2
3
2
Catalyst
1 2
2
BrCH CH Br
Br
Br
H
The hybridisation states of carbon atoms 1, 2, 3, 4
are
[MP PET 1994]
(a) 1 and 2 ;
2
sp 3 and 4
3
sp
(b) 1 and 2 ;
2
sp 3 and 4 sp
(c) 1, 2, 3 and 4 sp
(d) 1, 2 ;
3
sp
2
sp
17. In which of the compounds given below is there
more than one kind of hybridisation ( , , )
2 3
spsp sp
for carbon
(i)
3 2 2 3
(ii)
3 3
(iii)
2 2
(iv) H C C H [CBSE PMT 1995]
(a) ( ii ) and ( iv ) (b) ( i ) and ( iv )
(c) ( ii ) and ( iii ) (d) ( ii )
18. Examine the following common chemical
structures to which simple functional groups are
often attached
(i) (ii)
(iii) (iv)
3 2 2 2
(v)
2
Which of these systems have essentially planar
geometry
[CBSE PMT 1995]
(a) ( i ) and ( v ) (b) ( ii ) and ( iii )
(c) ( ii ), ( iii ) and ( iv ) (d) ( iv )
19. The structure of di-chloromethane is [MP PMT 1995]
(a) Tetrahedral (b) Trigonal
(c) Linear (d) Hexagonal
20. The numbers of sigma ( ) bonds in 1-butene is
[MP PMT 1995]
(a) 8 (b) 10
(c) 11 (d) 12
21. Which of the following statements is false for
isopentane
[MP PET 1996]
(a) It has three
3
CH groups
(b) It has one
2
CH group
(c) It has one CH group
(d) It has a carbon which is not bonded to
hydrogen
22. The number of bonds in o- xylene is [MP PET 1996]
(a) 6 (b) 9
(c) 12 (d) 18
23. In benzene the total number of bonds is [MP PMT 1997]
(a) 3 (b) 6
(c) 9 (d) 12
(a) 1, 2-butadiene (b) 1, 3-butadiene
(c) 1, 3-pentadiene (d) -butylene
45. In which of the following species is the
underlined carbon having
3
sp hybridisation [AIEEE 2002]
(a) CH COOH
3
(b) CH CHOH
3 2
(c)
3 3
(d)
2 3
46. The H C H bond angle in
4
CH is [MP PET 2002]
(a) 109 28 '
o
(b) 107 28 '
o
(c)
o
90 (d)
o
180
47. The hybridisation of carbons of C C
single bond
of
2
HC C CH CH is [RPMT 2002]
(a)
3 3
sp sp (b)
2
sp sp
(c) sp sp
3
(d)
2 3
sp sp
48. The shape of ethylene molecule is [AFMC 2002]
(a) Square planar (b) Furan
(c) Trigonal planar (d) Tetrahedral
49. Acetylene molecule has carbon in [Kerala (Engg.) 2002]
(a) sp - hybridisation (b)
2
sp - hybridisation
(c)
3
sp - hybridisation (d) sp d
3
makes use of
[DPMT 2001; MP PMT 2002]
(a) sp - hybridised orbitals (b)
2
sp - hybridised orbitals
(c)
3
sp - hybridised orbitals (d) Unhybridised orbitals
51. In graphite C- atom is in ....state [CPMT 2002]
(a)
3
sp (b) sp
(c)
2
sp (d) None of these
52. How many -bonds are present in naphthalene
molecule
[RPMT 2002]
(a) 3 (b) 4
(c) 5 (d) 6
53. Hybridisation state of C in diamond is [RPMT 2002]
(a) sp
(b)
2
sp
(c)
3
sp (d) spd
3
54. The number of and bonds present in pent- 4 -
ene, 1-yne is [AIIMS 2002; CPMT 2002]
(a) 10, 3 (b) 3, 10
(c) 4, 9 (d) 9, 4
55. Which one of the following is more acidic [DPMT 2002]
(a) Butane (b) 1 - butene
(c) 1 - butyne (d) 2 - butyne
56. Graphite is soft while diamond is hard because [BHU 2003]
(a) Graphite is in powder form
(b) Diamond has
2
sp hybridization but graphite
has
3
sp hybridization
(c) Graphite is in planar form while diamond is in
tetrahedral form
(d) Graphite is covalent and diamond is ionic
57. Hybridization of 1 and 2 carbon atoms in
2
1 2
2
(a) sp , sp
(b)
2 2
sp , sp
(c) sp , sp
2
(d)
3 2
sp , sp
58. Hydrogen bonding is maximum in [UPSEAT 2003]
(a) C HOH
2 5
(b)
3 3
(c) CH C O
3 2
( ) (d) CH CHO
3
59. How many methyl group are present in 2, 5 -
dimethyl- 4 - ethylheptane [EAMCET 2003]
(a) 2 (b) 3
(c) 4 (d) 5
60. Which one of the following does not have
2
sp
hybridised carbon [AIEEE 2004]
(a) Acetonitrile (b) Acetic acid
(c) Acetone (d) Acetamide
61. Allyl cyanide contain - and -bonds [MP PET 2004]
(a) 9 , 3 (b) 9 , 9
(c) 3 , 4 (d) 5 , 7
62. Strongest acid is [MP PMT 2004]
(a) HC CH
(b)
2 6
(c)
6 6
CH (d) CH OH
3
63. C C bond is found in [BHU 1982; MP PMT 1994]
(a) Ethene (b) Butene
(c) Ethyne (d) Glycerine
64. Number of bonds in [CPMT 1994]
(a) 6 (b) 15
(c) 10 (d) 12
65. Number of bonds in benzene [DPMT 2005]
(a) 6 and 3 (b) 12 and 3
(c) 3 and 12 (d) 6 and 6
66. Which is most acidic of the following [J & K 2005]
(a) Methane (b) Acetylene
(c) 1 - butene (d) Neo-pentane
67. The enolic form of acetone contains [Pb. PMT 2002]
(a) 8 bonds, 2 -bonds and 1 lone pairs
(b) 9 -bonds, 1 -bond and 2 lone pairs
(c) 9 -bonds, 2 -bonds and 1 lone pairs
(d) 10
1. Which has zero dipole moment [NCERT 1990; BHU 2001]
(a) cis - 2 - butene (b) trans - 2 - butene
(c) 1 - butene (d) 2 - methyl- 1 - propene
2. Dipole moment is shown by [DCE 1999]
(a) 1, 4-dichloro benzene
(b) Cis-1, 2-dichloro ethane
(c) Trans-1, 2-dichloro, 2-pentene
(d) Trans-1, 2-dichloro ether
3. Which compound shows dipole moment [RPMT 2002]
(a) 1,4-di-chloro benzene
(b) 1, 2-di-chloro benzene
(c) Trans-1, 2-di-chloro ethene
(d) Trans- 2 - butene
4. Which of the following is a polar compound
[MH CET 2003]
(a)
2 6
(b)
4
CCl
(c) HCl (d)
4
5. The dipole moment is the highest for [AIIMS 2004]
(a) Trans - 2 - butene (b) 1, 3-Dimethylbenzene
(c) Acetophenone (d) Ethanol
6. Resonance structure of molecule does not have
[IIT-JEE 1984]
(a) Identical arrangement of atoms
(b) Nearly the same energy content
(c) The same number of paired electrons
(d) Identical bonding
7. All bonds in benzene are equal due to
[Roorkee 1990; KCET 1998]
(a) Tautomerism (b) Inductive effect
(c) Resonance (d) Isomerism
8. Aromatic properties of benzene are proved by
[MP PMT 1994]
(a) Aromatic sextet theory (b) Resonance theory
(c) Molecular orbital theory (d) All of these
9. Which of the following will show aromatic
behaviour
[KCET 1996]
(a) (b)
(c) (d)
10. Which one of the following orders is correct
regarding the inductive effect of the substituents [CBSE PMT 1998]
(a) NR OR F
2
(b) NR OR F
2
(c) NR OR F
2
(d) NR OR F
2
11. Benzene is unreactive because [KCET 1998]
(a) It has double bonds
(b) It has carbon-carbon single bond
(c) Carbon are
2
sp hybridised
(d) electrons are delocalised
12. Carboxylic acids are easily ionised. The main
reason of this statement [UPSEAT 1999]
(a) Absence of -hydrogen
(b) Resonance stabilisation of carboxylate ion
(c) Reactivity of -hydrogen
(d) Hydrogen bond
13. ' C C 'bond length in benzene lies between single
and double bond. The reason is [RPET 1999]
(a) Resonance (b) Isomerism
(c) Metamerism (d) Inductive effect
14. Credit for the ring structure of benzene goes to
[RPET 1999]
(a) Wholer (b) Faraday
(c) Kekule (d) Baeyer
15. Polarisation of electrons in acroline may be
written as
[DCE 2000]
(a) CH CH CH O
2
(b)
CH CH CH O
2
(c) CH CH CH O
2
(d)
CH CH CH O
2
16. In the mixture of conc.
2 4
HSO and
3
HNO the
nitrating species is [MP PMT 2000]
(a)
2 4
NO (b)
2
NO
(c)
2
NO (d)
2
NO
17. Which of the following are not aromatic [DCE 2001]
(a) Benzene
(b) Cyclo-octatetrarenyl dianion
(c) Tropyllium cation
(d) Cyclopentadienyl cation
18. Arrangement of
3 3 23 3 2 3
when
attached to benzyl or an unsaturated group in
increasing order of inductive effect is [AIE
(a)
3 3 32 3 2
(b) CH CH CH CH CH C
3 2 32 33
(c)
3 2 33 3 2
(d) CH C CH CH CH CH
2 3 3 2 32
19. Which of the following is observed in ethylene
molecule
[MH CET 2002]
(a) Electromeric effect (b) Inductive effect
(c) Homolytic fission (d) None of these
20. Cyclopentadienyl anion is [Orissa JEE 2003]
(a) Aromatic (b) Non-aromatic
(c) Non-planar (d) Aliphatic
21. Orbital interaction between the sigma bonds of a
substitutent group and a neighbouring pi orbital
is known as
[BHU 1985]
(a) Carbocation (b) Carbanion
(c) Free radical (d) None of these
36. Which of the following carbanion is most stable
[NCERT 1983]
(a) Methyl (b) Primary
(c) Secondary (d) Tertiary
37. Among the given cations, the most stable
carbonium ion is
[IIT-JEE 1981]
(a) sec - butyl (b) ter - butyl
(c) n - butyl (d) None of these
38. In the compound given below
The correct order of the acidity of the positions
( X ), ( Y ) and ( Z ) is [IIT-JEE Screening 2004]
(a) ( Z ) > ( X ) > ( Y ) (b) ( X ) > ( Y ) > ( Z )
(c) ( X ) > ( Z ) > ( Y ) (d) ( Y ) > ( X ) > ( Z )
39. C-C bond length in benzene is
[MP PMT 1987; MP PMT 2001; AIIMS 2001]
(a) 1.39 Å
(b) 1.
Å
(c) 1.34 Å
(d) Different in different bonds
40. Heterolysis of carbon-chlorine bond produces
[MNR 1986; MP PET/PMT 1998]
(a) Two free radicals
(b) Two carbonium ions
(c) Two carbanions
(d) One cation and one anion
41. In , 3 2
CHCHOH the bond that undergoes
heterolytic cleavage most readily is [IIT-JEE 1988]
(a) C – C (b) C – O
(c) C – H (d) O – H
42. Which of the following intermediate have the
complete octet around the carbon atom [Orissa JEE 2003]
(a) Carbonium ion (b) Carbanion ion
(c) Free radical (d) Carbene
43. A solution of D (+) - 2 - chloro- 2 - phenylethane in
toluene racemises slowly in the presence of small
amount of ,
5
SbCl due to the formation of [IIT-JEE 1999]
(a) Carbanion (b) Carbene
(c) Free radical (d) Carbocation
44. The reagent in Friedel Craft's reaction is [DPMT 2005]
(a) Pyridine (b) RCOCl
(c) RCOOH (d) HCl
45. Which gives monosubstituted product [DPMT 2005]
(a) o - dinitrobenzene (b)
m
(c) p
should have a -electron cloud containing
electrons where n can't be
[J & K 2005]
(a) 1/2 (b) 3
(c) 2 (d) 1
47. Which of the following is an electrophile [J & K 2005]
(a) H O
2
(b)
3
(c)
3
NH (d) ROR
48. The presence of the chlorine atom on benzene
ring makes the second substituent enter at a
position [J & K 2005]
(a) ortho (b) meta
(c) para (d) ortholpara
49. Which is the most stable carbocation [J & K 2005]
(a) iso-propyl (b) Triphenylmethyl
cation
(c) Ethyl cation (d) -propyl cation
1. To which of the following four types does this
reaction belong
B R A B R A [Manipal MEE 1995]
(a) Unimolecular electrophilic substitution
(b) Bimolecular electrophilic substitution
(c) Unimolecular nucleophilic substitution
(d) Bimolecular nucleophilic substitution
2. An alkyl halide may be converted into an alcohol
by
[Pb. PMT 2000]
(a) Elimination (b) Addition
(c) Substitution (d) Dehydrohalogenation
CH CH Cl
3 2
The above reaction proceeds through [AMU 2000]
(a) Nucleophilic substitution
(b) Electrophilic substitution
(c) Free radical substitution
(d) More than one of the above processes
4. Geometry of reaction intermediate in
1
SN
reaction is
[MH CET 2001]
(a) Tetrahedral (b) Planar
(c) Triangular bipyramidal (d) None of these
OH KBr
CH
CH
Br KOHAq HC C
CH
CH
H C C
3
3
|
|
3
3
3
|
|
3
( .)
above reaction is [RPMT 2003]
( X )
3
( Z )
( Y )
(a)
1
SN (b)
2
SN
(c)
1
E (d) Both (a) and (b)
6. In electrophilic substitution reaction nitrobenzene is
[Kerala (Med.) 2003]
(a) Meta-directing
(b) Ortho-directing
(c) Para-directing
(d) Not reactive and does not undergo any
substitution
(e) Non-selective
7. The most common type of reaction in aromatic
compounds is [Orissa JEE 2003]
(a) Elimination reaction
(b) Addition reaction
(c) Electrophilic substitution reaction
(d) Rearrangement reaction
8. The function of 3
AlCl in Friedel-Craft’s reaction is
[KCET 2003]
(a) To absorb HCl (b) To absorb water
(c) To produce nucleophile (d)To produce electrophile
9. Which of the following can’t be used in Friedal
Craft’s reactions [AFMC 2004]
(a)
3
FeCl (b)
2
FeBr
(c)
3
AlCl
(d) NaCl
10. The nitration of a compound is due to the [Pb. PMT 2004]
(a)
2
NO (b)
3
(c) NO (d)
2
11. Dehydrohalogenation of an alkyl halide is a/an
[MH CET 2004]
(a) Nucleophilic substitution reaction
(b) Elimination reaction
(c) Both nucleophilic substitution and elimination
reaction
(d) Rearrangement
12. Addition of HCl to vinyl chloride gives 1, 1 -
dichloroethane because of [MP PET 2004]
(a) Mesomeric effect of Cl
(b) Inductive effect of Cl
(c) Restricted rotation around double bond
(d) None of these
13. Formation of ethylene from acetylene is an
example of
(a) Elimination reaction (b) Substitution reaction
(c) Addition reaction (d) Condensation
reaction
14. Conversion of 4
CH to CHCl
3
is an example of
which of the following reaction [Pb. CET 2001]
(a) Electrophilic substitution
(b) Free radical addition
(c) Nucleophilic substitution
(d) Free radical substituion
15. Following reaction,
CH CBr HO CH COH HBr
3 3 2 33
( ) ( ) is an example
of
[DCE 2002]
(a) Elimination reaction (b) Free radical
substitution
(c) Nucleophilic substitution(d)Electrophilic substitution
16. Which is an electrophile [DCE 2002]
(a)
3
BCl
(b) CHOH
3
(c)
3
NH (d)
4
AlCl
17. The electrophile in the nitration of benzene is
[Orissa JEE 2004]
(a)
2
NO (b)
2
(c)
NO (d)
2
NO
18. The following compound will undergo
electrophilic substitution more readily than
benzene [UPSEAT 2004]
(a) Nitrobenzene (b) Benzoic acid
(c) Benzaldehyde (d) Phenol
19. Which represents nucleophilic aromatic
substitution reaction
[Orissa JEE 2004]
(a) Reaction of benzene with
2
Cl in sunlight
(b) Benzyl bromide hydrolysis
(c) Reaction of NaOH with dinitrofluorobenzene
(d) Sulphonation of benzene
20. Which is an electrophile [DCE 2000]
(a)
3
AlCl (b)
CN
(c)
3
(d) CH OH
3
21. Strongest nucleophile is [BHU 2003]
(a)
2
RNH (b) ROH
(c)
C H O
6 5
(d)
CH O
3
22. The major product obtained when Br / Fe
2
is
treated with
is
[IIT-JEE Screening 2004]
(a) (b)
(c) (d)
23. Which one of the following is least reactive in a
nucleophilic substitution reaction [CBSE PMT 2004]
(a) CH CHCl
3 2
(b) CH CHCH Cl
2 2
3
Br
Br
3
Br
3
Br
[CBSE PMT 1988]
(a)
3
3
(b)
2 2 2 3
(c)
2
3 3
(d)
2
3 2 3
8. Which of the following compounds may not exist
as enantiomers [CPMT 1987]
(a) CH CHOHCOH
3 2
(b) CH CHCHCH CH OH
3 2 3 2
(c)
6 5 2 3
(d)
6 5 3
CHCHClCH
9. Number of isomers of molecular formula
2 2 2
CHBr
are
[CPMT 1987]
(a) 1 (b) 2
(c) 3 (d) 0
10. Lactic acid shows which type of isomerism
[CPMT 1987; MP PMT 1987; BHU 2003]
(a) Geometrical isomerism (b) Tautomerism
(c) Optical isomerism (d) Metamerism
11. Which one of the following is an optically active
compound
[CBSE PMT 1988; DPMT 1983]
(a) n - propanol (b) 2 - chlorobutane
(c) n - butanol (d) 4 - hydroxyheptane
12. Compounds with same molecular formula but
different structural formulae are called [BHU 1979; AFMC 1989]
(a) Isomers (b) Isotopes
(c) Isobars (d) Isoelectronic
13. Which one of the following compounds shows
optical isomerism [MP PET 1990]
(a)
3 2 3
CH CHCl CH CH
(b)
3 2 2 3
CH CH CHCl CH CH
(c)
2 2 2 3
ClCH CH CH CH
(d)
2 2 3
ClCH CH CH
14. Which one of the following objects is ‘achiral’
(a) Letter P (b) Letter F
(c) Ball (d) A pair of hand
15. Total number of isomers of a disubstituted
benzene compound is
(a) 1 (b) 2
(c) 3 (d) 4
16. Separating of d and l enantiomorphs from a
racemic mixture is called [CBSE PMT 1988; DPMT 1983;
KCET 2002]
(a) Resolution (b) Dehydration
(c) Rotation (d) Dehydrohalogenation
17. Number of optical isomers of lactic acid are
(a) 1 (b) 2
(c) 3 (d) 4
18. Which one of the following contains asymmetric
carbon atom [IIT-JEE 1989; Roorkee 2000]
(a) H
Br
Cl
(b) Cl
Cl
(c) H
(d)
3
Br
19. n - butane and isobutane are examples of
(a) Chain isomers (b) Geometrical isomers
(c) Position isomers (d) Tautomers
20. Which of the following has chiral structure
(a) CHCOOH
2
3
3
(b)
3 3
(c) CHOH
2
3
3
(d)
3 2 3
21. Which of the following pairs is an example of
position isomerism
(a)
3 2 2 3
CH CH CH CH and
3
3
3
|
CH
CH
CH CH
(b)
3 2 2
CH CH CH CH and
3 3
(c) CH CHOH
3 2
and
3 3
(d)
3
3
3 3
|
|
CH
CH
CH C CH and
3 2 2 2 3
22. Geometrical isomerism is shown by
[IIT-JEE 1983; CPMT 1990, 94; CBSE PMT 1992;
MP PET 1997; AMU (Engg.) 1999]
(a) 2 - butene (b) 2 - butyne
(c) 2 - butanol (d) Butanal
23. An organic compound exhibits optical isomerism
when
[CPMT 1971, 78, 81; MP PET 1999]
(a) Four groups linked to carbon atom are
different
(b) Three groups linked to carbon atom are
different
(c) Two groups linked to carbon atom are
different
(d) All the groups linked to carbon atom are same
24. Which one of the following exhibits geometrical
isomerism
[NCERT 1979; DPMT 1984; CBSE PMT 1990]
(a)
3 3
CH
H
C C
HC
H
(b)
2
(c)
H
H
C C
CH
CH
3
3
(d)
|
3
|
|
25. Maximum number of isomers of alkene 4 8
CH are
[IIT-JEE 1982; MP PMT 1985; MADT Bihar 1995;
Kerala (Engg.) 2002]
(a) 2 (b) 3
(c) 4 (d) 6
26. Rotation of plane polarised light is measured by
[CPMT 1985; DCE 2001]
(a) Manometer (b) Polarimeter
(c) Viscometer (d) Refractometer
27. An alkane forms isomers if the number of least
carbon atom is [CPMT 1976; BHU 1985, 89]
(a) 1 (b) 2
(c) 3 (d) 4
28. Which is not found in alkenes [AIIMS 1982; RPMT 1999]
(a) Chain isomerism (b) Geometrical
isomerism
(c) Metamerism (d) Position isomerism
29. How many isomers of C H OH 5 11
will be primary
alcohols
[CBSE PMT 1992]
(a) 2 (b) 3
(c) 4 (d) 5
30. The compound C H O 4 10
can show
[IIT-JEE 1981; MP PET 2000]
(a) Metamerism (b) Functional
isomerism
(c) Positional isomerism (d) All types
31. The number of possible alcoholic isomers for
4 10
are
[DPMT 1984; MNR 1986]
(a) 4 (b) 2
(c) 3 (d) 5
32. How many isomers are possible for C HO 4 8
[MNR 1992; UPSEAT 2001, 02]
(a) 3 (b) 4
(c) 5 (d) 6
33. Which of the following can exhibit cis-trans
isomerism
[CBSE PMT 1989]
(a) HC CH (b) ClCH = CHCl
(c) CH. CHCl. COOH
3
(d) ClCH CHCl
2 2
34. The number of geometrical isomers in case of a
compound with the structure
3 2 5
CH CH CH CH CH CH is
[NCERT 1980]
(a) 4 (b) 3
(c) 2 (d) 5
35. The property by virtue of which a compound can
turn the plane polarised light is known as [BHU 1979]
(a) Photolysis (b) Phosphorescence
(c) Optical activity (d) Polarization
36. Meso-tartaric acid is optically inactive due to the
presence of
[AIIMS 1982; MP PMT 1987]
(a) Molecular symmetry
(b) Molecular asymmetry
(c) External compensation
(d) Two asymmetric C-atoms
37. Which of the following compounds exhibits
optical isomerism [BHU 1983; AFMC 1990; CPMT 1993;
MP PMT 1999, 2000]
(a) CH CHCOOH
3 2
(b) CH CHOHCOOH
3
(c) CH CHCHOH
3 2 2
(d)
3 3
38. The maximum number of stereoisomers possible
for 2-hydroxy- 2 - methyl butanoic acid is [Roorkee 1992]
(a) 1 (b) 2
(c) 3 (d) 4
39. Which one of the following pairs represents the
stereoisomerism [AIIMS 1992]
(a) Geometrical isomerism, position isomerism
(b) Geometrical isomerism, conformational
isomerism
(c) Optical isomerism, geometrical isomerism
(d) Optical isomerism, metamerism
40. Diethyl ether is not associated with which one of
these isomers [AFMC 1993]
(a) Butanoic acid (b) Methyl propionate
(c) Steroisomerism (d) None of these
41. Diethyl ether and methyl n- propyl ether are
[MP PET 1994; AFMC 1999; MP PMT 2002]
(a) Position isomers (b) Functional isomers
(c) Metamers (d) Chain isomers
42. n- propyl alcohol and isopropyl alcohol are
examples of
[MP PMT 1994]
(a) Position isomerism (b) Chain isomerism
(c) Tautomerism (d) Geometrical
isomerism
43. It is possible to distinguish between optical
isomers by
63. cis and trans 2 - butene are [BHU 1998; DPMT 2002]
(a) Conformational isomers (b) Optical isomers
(c) Position isomers (d) Geometrical isomers
64. Which one of the following is the chiral molecule
[BHU 1998; 2005]
(a) CH Cl
3
(b)
2 2
CHCl
(c)
3
CHBr (d) CHClBrI
65. Cyanide and isocyanide are isomers of type [AFMC 1997]
(a) Positional (b) Functional
(c) Tautomer (d) Structural
66. Glucose and fructose are [AMU (Engg.) 1999]
(a) Optical isomers (b) Functional isomers
(c) Position isomers (d) Chain isomers
67. Which of the following compounds which is an
optically active compound [UPSEAT 1999]
(a) 1 - butanol (b) 2 - butanol
(c) 3 - butanol (d) 4 - heptanol
68. d - tartaric acid and l - tartaric acid are [MH CET 1999]
(a) Enantiomers (b) Tautomers
(c) Diastereoisomers (d) Structural isomers
69. Minimum resistance in bond rotation will be
observed in the compound [RPMT 1999]
(a) Hexachloroethane (b) Ethylene
(c) Acetylene (d) Ethane
70. Which pair show cis-trans isomerism [RPET 1999]
(a) Maleic-fumaric acid (b) Lactic-tartaric acid
(c) Malonic-succinic acid (d)Crotonic-acrylic acid
71. 1, 2-Dichloroethene shows [RPET 1999]
(a) Geometrical isomerism (b) Optical isomerism
(c) Ring-chain isomerism (d) Resonance
72. Which compound is optically active [DCE 1999]
(a) 4 - chloro, 1 hydroxy butane
(b)
o
3
(c) Secondary butyl amine
(d) n - butyl alcohol
73. Choose the pair of chain isomer [RPMT 2000]
(a)
3 2
CHCHBr and CH BrCHBr
2 2
(b) 1 - propanol and 2-propanol
(c) Neo-pentane and isopentane
(d) Diethyl ether and methyl- n - propyl ether
74. Optical isomerism arises due to the presence of
[RPMT 2000]
(a) An asymmetric carbon atom
(b) Centre of symmetry
(c) Axis of symmetry
(d) Plane of symmetry
75. Least hindered rotation about carbon-carbon bond
is observed in [RPMT 2000]
(a) Ethane (b) Ethylene
(c) Ethyne (d) Hexachloroethane
76. Which pair represents chain isomer [RPMT 2000]
(a)
3 2
CHCHCl and ClCH CHCl
2 2
(b) n - propyl alcohol and isopropyl alcohol
(c) 2 - methy l - 1 propanol and 2-Methyl-2 propanol
(d) 2 - methyl butane and neopentane
77. Which of the following compounds will exhibit
geometrical isomerism [IIT-JEE Screening 2000]
(a) 1 - phenyl- 2 - butene (b) 3 - phenyl- 1 - butene
(c) 2 - phenyl- 1 - butene (d) 1, 1 - Diphenyl- 1 -
propene
78. On bromination, propionic acid yields two
isomeric 2-bromopropionic acids. This pair is an
important example of [BHU 2000]
(a) Chain isomers (b) Optical isomers
(c) Cis-trans isomers (d) Position isomers
79. Geometrical isomerism is not possible in [CPMT 2000]
(a) Propene (b) 3 - hexane
(c) Butenedioic acid (d) Cyclic compound
80. Only two isomeric monochloro derivatives are
possible for
[Pb. PMT 2000]
(a) 2 - methyl propane (b) n - pentane
(c) Benzene (d) 2, 4 - dimethyl
pentane
81. Lactic acid in which a methyl group, a hydroxyl
group, a carboxylic acid group and a hydrogen
atom are attached to a central carbon atom,
shown optical isomerism due to the molecular
geometry at the [Pb. PMT 2000]
(a) Central carbon atom
(b) Carbon atom of the methyl group
(c) Carbon atom of the carboxylic acid group
(d) Oxygen of the hydroxyl groups
82. The number of possible alkynes with molecular
formula
5 8
CH is [MP PMT 2000]
(a) 2 (b) 3
(c) 4 (d) 5
83. Which of the following will not lose asymmetry
on reduction with
4
LiAlH [Roorkee 2000]
(a)
2
2 2 3
(b)
2 3
3
2
(c)
3
2
(d)
2 2
3
84. Reason for geometrical isomerism by 2-butene is
[CBSE PMT 2000]
(a) Chiral carbon
(b) Free rotation about single bond
(c) Free rotation about double bond
(d) Restricted rotation about double bond
85. Stereoisomers which are not the mirror images of
one another are called [RPMT 2000]
(a) Enantiomers (b) Mesomers
(c) Tautomers (d) Diasteroisomers
86. The isomerism shown by n - butyl alcohol and
isobutyl alcohol is [RPMT 2000]
(a) Metamerism (b) Chain
(c) Position (d) Stereo
87. Which is optically active [MH CET 2001]
(a)
2 2
CHCl
(b)
3
CHCl
(c) Meso form of tartaric acid
(d) Glyceraldehyde
88. Which of the following will show geometrical
isomerism
[CPMT 2001; BHU 2005]
(a)
3 3
(b)
3 2 32
(c)
3 2 32
(d)
3 32
89. What is the maximum number of open chain
structures possible for
4 8
(a) 2 (b) 3
(c) 4 (d) 1
90. Glucose has optical isomers [DCE 2001]
(a) 8 (b) 12
(c) 16 (d) Cannot be predicted
91. An organic compound
3
7
2
6
2
5
2
4
2
3
2
2
3
1
CH CH CH CH CH CH CH
To make it chiral compound the attack should be
on which carbon atom [DCE 2001]
(a) 1 (b) 3
(c) 4 (d) 7
92. Which of the following statements is not true
about enantiomers [DCE 2001]
(a) They have same physical properties
(b) They have different biological properties
(c) They have same chemical properties towards
chiral compounds
(d) None of these
93. Meso-tartaric acid is [BHU 2001]
(a) Optically inactive
(b) Optically active because of molecular
symmetry
(c) Optically inactive due to external
compensation
(d) Optically active because of asymmetric carbon
atom
94. The number of possible isomers of the compound
with molecular formula C HO
7 8
is [BHU 2001]
(a) 3 (b) 5
(c) 7 (d) 9
95. The number of isomers for the compound with
molecular formula CBrClFI
2
is [IIT-JEE (Screening) 2001]
(a) 3 (b) 4
(c) 5 (d) 6
96. Hydrogenation of the adjoining compound in the
presence of poisoned palladium catalyst gives
[IIT-JEE (Screening) 2001]
Me H
MeH
(a) An optically active compound
(b) An optically inactive compound
(c) A racemic mixture
(d) A diastereomeric mixture
97. The number of possible structural isomers for a
compound with the molecular formula
7 16
CH is [DCE 2001]
(a) 8 (b) 9
(c) 10 (d) 12
98. Which of the following molecule contains
asymmetric carbon atom [JIPMER 2002]
(a) CHCHClCOOH
3
(b) CH CHCOOH
3 2
(c) ClCH CHCOOH
2 2
(d) ClCHCOOH
2
99. A similarity between optical and geometrical
isomerism is that [AIEEE 2002]
(a) Each forms equal number of isomers for a
given compound
(b) If in a compound one is present then so is the
other
(c) Both are included in stereoisomerism
(d) They have no similarity
100. If the light waves pass through a nicol prism then
all the oscillations occur only in one plane, such
beam of light is called as [Kerala (Med.) 2002]
(a) Non-polarised light (b) Plane polarised light
(c) Polarised light (d) Optical light
101. Racemic mixture is formed by mixing two [AIEEE 2002]
(a) Isomeric compounds (b) Chiral compounds
(c) Meso compounds (d) Optical isomers
102. Which of the following does not show geometrical
isomerism [AIEEE 2002]
(a) 1, 2 dichloro- 1 - pentene
(b) 1, 3-dichloro- 2 - pentene
(c) 1, 1-dichloro- 1 - pentene
(d) 1, 4-dichloro- 2 - pentene
Me
120. An enantiomerically pure acid is treated with
racemic mixture of an alcohol having one chiral
carbon. The ester formed will be [IIT-JEE (Screening) 2003]
(a) Optically active mixture (b) Pure enantiomer
(c) Meso compound (d) Racemic mixture
121. Which one of the following will not show
geometrical isomerism [MP PMT 2003]
(a)
H Br
HC Cl
3
(b)
HC Br
HC Cl
3
3
(c)
D Br
H Cl
(d)
Br Br
Cl Cl
122. Isomerism shown by
3 23 3
3 2 2 2 3
2 3
3
3
|
O CH CH
CH
CH CH is [RPMT 2003]
(a) Position isomerism (b) Chain isomerism
(c) Metamerism (d) Optical isomerism
123. A compound whose molecules are superimposable
on their mirror images even through they contain
an asymmetric carbon atom is called [Kerala (Med.) 2003]
(a) A meso compound (b) An erythro isomer
(c) A threo isomer (d) a glycol
124. Of the following, the compound possessing optical
isomerism [Kerala (Med.) 2003]
(a) CH CHOH
3 2
(b) CHCHClBr
3
(c) CCl BrF
2
(d)
2 2
CClF
125. Which of the following statement is wrong [EAMCET 2003]
(a) Diethyl ketone and methyl propyl ketone are
position isomers
(b) 2 - chloro pentane and 1 - chloro pentane are
position isomers
(c) n - butane and 2 - methyl propane are chain
isomers
(d) Acetone and propinaldehyde are functional
isomers
126. Dimethyl ether and ethyl alcohol are
[MH CET 2004; Pb. CET 2002]
(a) Metamers (b) Homologues
(c) Functional isomers (d) Position isomers
127. The correct statement about the compounds A
and B is
[DCE 2002; UPSEAT 2004; IIT-JEE 1997; DPMT 2005]
COOH
H OH
H OH
COOCH
3
3
COOCH
H OH
H OH
COOH
(a) A and B are identical
(b) A and B are diastereomers
(c) A and B are enantiomers
(d) None of these
128. Ethyl acetoacetate shows, which type of
isomerism
[Pb. CET 2003]
(a) Chain (b) Optical
(c) Metamerism (d) Tautomerism
129. Which of the following will have a mesoisomer
also
[AIEEE 2004]
(a) 2, 3-Dichloropentane
(b) 2, 3-Dichlorobutane
(c) 2 - Chlorobutane
(d) 2 - Hydroxypropanoic acid
130. For which of the following parameters the
structural isomers C HOH
2 5
and
3 3
CHOCH would
be expected to have the same values? (Assume
ideal behaviour) [AIEEE 2004]
(a) Boiling points
(b) Vapour pressure at the same temperature
(c) Heat of vaporization
(d) Gaseous densities at the same temperature
and pressure
131. The geometrical isomerism is shown by [AIIMS 2004]
(a) (b)
(c) (d)
132. Which of the following compounds will exhibit
cis-trans isomerism [Kerala PMT 2004]
(a) 2 - butene (b) 2 - butyne
(c) 2 - butanol (d) Butanone
(e) Butanol
133. Which of the following compounds exhibit
stereoisomerism
[MP PMT 2004]
(a) 2 - methyl-butane I (b) 3 - methyl-butanoic
acid
(c) 3 - methyl-butyne I (d) 2 - methyl butanoic
acid
134. The chirality of the compound [CBSE PMT 2005]
HC Cl
H
Br
C
3
|
(a) R (b) S
(c) Z (d) E
135. Which of the following is most likely to show
optical isomerism [UPSEAT 2004]
(a) C CH
Cl
|
|
(b)
3
|
|
Cl
2
2
CH Cl
CH Cl
(c) H
Cl
|
|
(d)
2
|
Cl
136. Nitroethane can exhibit one of the following kind
of isomerism [DCE 2004]
(a) Metamerism (b) Optical activity
(c) Tautomerism (d) Position isomerism
3
shows [BVP 2004]
(a) Geometrical isomerism (b) Optical isomerism
(c) Both (d) None
138. Which will have enantiomer [BVP 2004]
(a)
3
|
3 2
CH
Cl
CH CH CH (b) CH CHCHCHCl
2 2 2 2
(c)
3 2 2 2
CHCHCHCHCl
(d) None
139. The total number of acylic isomers including the
stereoisomers with the molecular formula C HCl
4 7
[Pb. CET 2004]
(a) 11 (b) 12
(c) 9 (d) 10
140. The number of possible enantiomeric pairs that
can be produced during mono-chlorination of 2-
methylbutane is
[Pb. CET 2004]
(a) 3 (b) 4
(c) 1 (d) 2
141. Which one of the following pairs represents
stereoisomerism
[CBSE PMT 2005]
(a) Chain isomerism and rotational isomerism
(b) Structural isomerism and geometric
isomerism
(c) Linkage isomerism and geometric isomerism
(d) Optical isomerism and geometric isomerism
142. When isomers have the same structural formula
but differ in relative arrangement of atoms or
groups are called
[CPMT 2000; KCET (Med.) 2000]
(a) Mesomers (b) Stereoisomers
(c) Optical isomers (d) Geometrical
mesomers
3 2 2
CH CH CH CH and
3 3
CH CH CH CH show
(a) Chain isomerism (b) Position isomerism
(c) Functional isomerism (d) Metamerism
144. The number of possible isomers of butene are
[Kerala (Engg.) 2002]
(a) 3 (b) 2
(c) 4 (d) 5
(e) 6
145. Which of the following show geometrical
isomerism
[BCECE 2005]
(a) C HBr
2 5
(b)
2 2
(c)
2 2
( CH )( COOH ) (d)
2 6
146. Among the following the most stable compound is
[AIIMS 2005]
(a) cis 1 , 2 cyclohexanediol
(b) trans 1 , 2 cyclohexanediol
(c) cis 1 , 3 cyclohexanediol
(d) trans 1 , 3 cyclohexanediol
147. Chirality of carbon compound is because of its
[Kerala (Med.) 2002]
(a) Tetrahedral nature of carbon
(b) Monovalent nature of carbon
(c) Divalent nature of carbon
(d) Trivalent nature of carbon
148. Which kind of isomerism is possible for 1-chloro-
2 - nitroethene [J & K 2005]
(a) Functional group isomerism
(b) Position isomerism
(c) E / Z isomerism
(d) Optical isomerism
149. Which will give chiral molecule [DPMT 2005]
(a)
4
3
LiAlH
CH COCl
(b)
H HO
CHMgBr
2
3
/
2 5
(c)
Cu
CH CHC H
3 2 2 5
( )
(d)
2
3
3
3
Cl
150. Which of the following will be chiral
[J & K 2005]
(a)
3 2
CHCHCl (b) CHCHBrCl
3
(c)
2
2
CDCl (d) CH ClBr
2
151. Which of the following fischer projection formula
is same as D - Glyceraldehyde [Kerala CET 2005]
(a)
2
(b)
2
(c)
2
(d)
2
(e)
2
14. The number of possible isomers for compound
C HClBr
2 3 2
is [MP PMT 1999]
(a) 2 (b) 3
(c) 4 (d) 5
15. The optically active tartaric acid is named as D-
(+)- tartaric acid because it has a positive [IIT-JEE 1999]
(a) Optical rotation and is derived from D - glucose
(b) pH in organic solvent
(c) Optical rotation and is derived from D (+)
glyceraldehyde
(d) Optical rotation only when substituted by
deuterium
16. Among the following compounds (I-III) the
correct order of reaction with electrophilic
reagent is [CBSE PMT 1997]
(a) II > III > I (b) III < I < II
(c) I > II > III (d) I = II > III
17. Carbocation which is most stable [BHU 2003]
(a)
3 2
CHCH (b)
3
(c)
6 5 2
CHCH (d)
3 2 2
18. Tautomerism is exhibited by
[CBSE PMT 1997; KCET 2002]
(a) CH CNO
3 3
( ) (b) CH NH
3 2
(c)
3 2
(d)
2 2
19. Which of the following will have geometrical
isomers
[MP PET 1996; MP PMT 1997; AFMC 1997]
(a) 2 - methylpropene (b) 2 - butene
(c) 1 - butene (d) Propene
20. Examine the following three pairs of possible
isomers
Now state whether the pairs represent identical
compounds or different isomers
(a) All three pairs represent different compounds
(b) ( ia ) and ( ib ) are identical; ( iia ) and ( iib ) are
identical; and ( iiia ) and ( iiib ) are identical
(c) ( ia ) and ( ib ) are isomers; ( iia ) and ( iib ) are
identical; and ( iiia ) and ( iiib ) are isomers
(d) ( ia ) and ( ib ) are identical; ( iia ) and ( iib ) are
identical, and ( iiia ) and ( iiib ) are isomers
21. Tautomerism is exhibited by [IIT-JEE 1998]
(a)
(b)
(c)
(d)
22. The following reaction is described as [CBSE PMT 1997]
3
25 3
3
3 25
( )
| |
( )
CH
CH CH
H
Br HO C
H
C
HC
CH CH
OH
(a)
2
SE (b)
1
SN
(c)
2
SN (d)
0
SN
23. Which one of the following represents eclipsed
form of ethane
(a) (b)
(c) (d) None of these
24. Which are the staggered forms of ethane
I I
I
II
I
Cl
Cl
(ia
)
(iia)
(iiia)
Cl
(ib
)
Cl
(iii
b)
(ii
b)
2
1
3
4
(a) 1 and 4 (b) 3 and 4
(c) 2 and 4 (d) 1 and 3
25. Which of the following is the most stable cation
[CBSE PMT 1988; MNR 1988; AIIMS 1985]
(a)
3 2 3
(b)
3
3 3
(c)
3 2 2 2
(d)
3
CH
26. In a reaction of ,
6 5
the major product (>
60%) is m - isomer, so the group Y is [AIIMS 1997; UPSEAT 2003]
(a) COOH (b)
2
(c) OH (d) Cl
27. Dehydrohalogenation in presence of
OH is
correctly represented by [Orissa JEE 2004]
(a) (b)
(c) (d)
28. Number of structural isomers of C H O 4 10
are
[CPMT 1983, 84, 89, 91; MADT Bihar 1984;
MNR 1984; MP PET 1997; Pb. PMT 1999; MH CET
2003]
(a) 3 (b) 6
(c) 7 (d) 10
29. Among the following the aromatic compound is
[AIIMS 2004]
(a) (b)
(c) (d)
30. Which of the following compounds are not
arranged in order of decreasing reactivity
towards electrophilic substitution [DCE 2003]
(a) Fluoro benzene > chloro benzene > bromo
benzene
(b) Phenol > n - propyl benzene > benzoic acid
(c) Chloro toluene > para-nitro toluene > 2 -
chloro- 4 - nitro toluene
(d) Benzoic acid > phenol > n - propyl benzene
31. Most stable carbonium ion is [Pb. CET 2004]
(a)
5
2
(b)
3 3
(c)
6 53
( ) (d)
6 5 2
32. Which one of the following species is most stable
[IIT-JEE 1995]
(a)
2 6 4 2
p ON CH CH
(b)
3 6 4 2
p CHO CH CH
(c)
6 4 2
p Cl CH CH
(d)
6 5 2
33. Which of the following gives most stable
carbocation by dehydration [RPMT 2002]
(a) CH CH OH
3 2
(b) CH C OH
3 3
(c) CH CH OH
3 2
(d)
3 2 2 3
34. Which of the following orders regarding relative
stability of free radicals is correct [UPSEAT 2004]
(a) 3° < 2° < 1° (b) 3° > 2° > 1°
(c) 1° < 2° > 3° (d) 3° > 2° < 1°
35. The + I effect of alkyl groups is in the order [DCE 2002]
(a) 2° > 3° > 1° (b) 1° > 2° > 3°
(c) 3° > 2° > 1° (d) None of these
36. Which one has asymmetric C - atom [Roorkee 1995]
(a)
Br
CH CH CH
|
3 2 2
(b)
3
3
3
| |
CH
CH
CH
Br
CH CH
(c)
3 2 3
Br
(d)
2 2 3
3
3
|
|
CH CH CH
Br
CH
CH C
37. Which of the following compounds will show
metamerism
[KCET 1996]
(a)
3 2 5
(b)
2 5 2 5
(c)
3 3
CH O CH (d)
3 2 5
38. How many carbon atoms in the molecule
2
are asymmetric
[MP PET 2001]
(a) 1 (b) 2
(c) 3 (d) None of these
39. Which of the following act as nucleophiles [Roorkee 1999]
(a)
3 2
CHNH (b)
RO
(c)
3
AlCl (d) CH MgBr
3
40. Which of the following has the highest
nucleophilicity
[IIT-JEE Screening 2000]
(a)
F (b)
OH
(c)
3
CH (d)
2
NH
41. Keto-enol tautomerism is found in
[IIT-JEE 1988; MADT Bihar 1995]
Br
Br
Br
Br