laboursonline – MCQs, Mock Tests | IIT JEE IIT JEE Isomerism And Stereochemistry

Which of the following pairs of compounds are tautomers ?

1. Propanol and propanone
2. 1-Propanol and 2-propanol
3. Ethanol and vinyl alcohol
4. Vinyl alcohol and ethanal.

✅ Correct Answer: 4

Which of the following compounds is isomeric with trimethyl amine ?

1. 1-Propanamine
2. 2-Propanamine
3. both
4. None.

✅ Correct Answer: 3

Total number of conformations of ethane are

1. 2
2. 3
3. 4
4. Infinite.

✅ Correct Answer: 4

Which of thefollowing conformations of n-butane is the least stable ?

1. Gauche
2. Anti
3. Eclipsed
4. Fully eclipsed.

✅ Correct Answer: 4

Number of dibromo derivatives possible for propane are

1. 2
2. 3
3. 1
4. 4

✅ Correct Answer: 4

The functional isomers of ethane nitrile is

1. Ethyl carbylamine
2. Methane nitrile
3. Methyl carbylamine
4. Propane nitrile.

✅ Correct Answer: 1

The functional isomers of ethers are

1. Ketones
2. Aldehydes
3. Alcohols
4. Esters.

✅ Correct Answer: 3

Which of the following alkanes can form only two monochloro derivatives ?

1. Hexane
2. 2-Methyl pentane
3. 23-Dimethylbutane
4. 3-Methyl pentane.

✅ Correct Answer: 3

The simplest alkane capable of exhibiting chain isomerism has ..... carbon atoms.

1. three
2. five
3. four
4. six.

✅ Correct Answer: 3

Which of the following compounds can exhibit geometrical isomerism ?

1. 1-Hexene
2. 2-Methyl-2-pentene
3. 3-Methyl-1-pentene
4. 2-Hexene.

✅ Correct Answer: 4

Which of the following can exist as diastereomers ?

1. Lactic acid
2. 1-Butene
3. 2-Butene
4. Ethane.

✅ Correct Answer: 3

The number of stereoisomers possible for 2 3-pentanediol is

1. two
2. three
3. four
4. five.

✅ Correct Answer: 3

The number of dichloro derivatives of naphthalene is

1. Ten
2. Fourteen
3. Six
4. Five.

✅ Correct Answer: 1

A compound whose molecules are superimposable on their mirror images even though they contain asymmetric carbon atoms is called

1. A threo compound
2. An erythro compound
3. Adissymmetric compound
4. A meso compound.

✅ Correct Answer: 4

The simplest alkene which is capable of exhibiting geometric isomerism has

1. 3 carbon atoms
2. 5 carbon atoms
3. 6 carbon atoms
4. 4 carbon atoms.

✅ Correct Answer: 4

Anthracene is isomeric with

1. Phenanthrene
2. Naphthalene
3. Benzene
4. None of these.

✅ Correct Answer: 1

A racemic mixture contains equal ........ of dextrorotatory and laevorotatory isomers.

1. No. of molecules
2. Masses
3. No. of moles
4. All the above are correct.

✅ Correct Answer: 4

Geometric isomerism will be exhibited by .

1. 1-Pentene
2. 3-Methyl-1-butene
3. 2-Pentene
4. All ot these compounds

✅ Correct Answer: 3

The compound which is not isomeric with diethyl ether is

1. n-Propyl methyl ether
2. 1-Butanol
3. 2-Methyl-2-propanol
4. Butanone

✅ Correct Answer: 2

The number of monosubstitutionderivatives possible for naphthalene is

1. one
2. two
3. three
4. four

✅ Correct Answer: 1

Which of the following compounds can show geometric isomerism ? .

1. Vinyl chloride
2. 1,1-Dichloroethene
3. 1,2-Dichloroentene
4. Trichloroethene

✅ Correct Answer: 3

The simplest alkane which can exhibit enantiomerism has

1. 5 carbon atoms
2. 6 carbon atoms
3. 7 carbon atoms
4. 4 carbon atoms

✅ Correct Answer: 3

Which of th efollowing isomerisms is shown by alkenes but not by alkanes ?

1. conformational
2. Optical
3. Geometric
4. Chain.

✅ Correct Answer: 3

Ethoxyethane and 1-methoxy propane are

1. Chain isomers
2. Position isomers
3. Metamers
4. Tautomers.

✅ Correct Answer: 3

Which of the following statements is false ?

1. Enantiomers have same m.p. and b.p.
2. A mixture containing equal amounts of enantiomers is optically inactive
3. Enantiomers have same chemical properties
4. A micture containing two enantiomers can be separated into fractions containing pure enantiomers.

✅ Correct Answer: 4

Which of the following is the functional isomer of methyl acetate ? .

1. Ethyl acetate
2. Propanoic acid
3. Ethyl formate
4. Propanone

✅ Correct Answer: 2

Which of the following compounds does not exhibit geometric isomerism ?

1. 11-Dichloro-2-butene
2. 12-Dichloro-2-butene
3. 11-Dichloro-1-butene
4. 23-Dichloro-2-butene.

✅ Correct Answer: 3

How many isomer are possible for methylanthracene

1. 2
2. 3
3. 4
4. 5

✅ Correct Answer: 4

n-Butane and iso-butane are .......... isomers

1. Chain
2. Position
3. Geometric
4. Optical.

✅ Correct Answer: 1

Which of the following compound will show stereoisomerism ?

1. 4-Chlorobutan-1-ol
2. Tertiary butyl alcohol
3. sec-butyl amine
4. n-butyl alcohol.

✅ Correct Answer: 3

Enantiomerism was discovered by

1. Vant Hoff and Le Bell
2. Louis Pasteur
3. Berzelius
4. Kolbe.

✅ Correct Answer: 2

Which of the following compounds can exist in mesoform ?

1. 12-Dichlorobutane
2. 23-Dichloropentane
3. 23-Dichlorobutane
4. none

✅ Correct Answer: 3

Which of th efollowing compounds is expected to be most reactive ?

1. Cyclohexane
2. Cyclopropane
3. Cyclobutane
4. Cyclopentene.

✅ Correct Answer: 2

Maleic acid and fumaric acid are

1. Position isomers
2. Geometric isomers
3. Enantiomers
4. Functional isomers

✅ Correct Answer: 2

The energy difference between staggered and eclipsed conformations of etane is about

1. 25 kJ/mole
2. 30 kJ/mole
3. 100 kJ/mole
4. 12.5 kJ/mole

✅ Correct Answer: 4

The least stable conformation of cyclohexane is

1. Boat
2. Chair
3. Twist boat
4. Half chair.

✅ Correct Answer: 1

Which of the following is responsible for the inability of meso compound to show optical activity ?

1. Absence of chirality centre
2. Presence of more than one chirality centres
3. Dissymmetric nature of its structure
4. Internal compensation.

✅ Correct Answer: 4

ow many chirality centres are present in the structrue 1-chloro-2-methylchlorohexane ?

1. 2
2. 3
3. 4
4. 1

✅ Correct Answer: 1

The simplest alcohol that can exhibit enantiomerism is .

1. 1-Propanol
2. 1-Butanol
3. 2-Propanol
4. 2-Butanol

✅ Correct Answer: 4

d and l forms of tartaric acid are mixed in equal proportions. The mixture is called

1. Utectic mixture
2. Azeotropic mixture
3. Diastereomers
4. Racemic mixture

✅ Correct Answer: 4

Which of th efollowing does not contain any asymmetric carbon but can show enantiomerism ?

1. Lactic acid
2. 13-Pentadiene
3. Trataric acid
4. 23-Pentadiene.

✅ Correct Answer: 4

Which of the following is a chiral molecule ?

1. 1-Chloropropane
2. 2-Chloropropane
3. 1-Chlorobutane
4. 2-Chlorobutane.

✅ Correct Answer: 4

A certain compound contain three chirality centres. The maximum number of stereoisomers it can have is

1. 8
2. 6
3. 9
4. 3

✅ Correct Answer: 1

Maleic acid and fumaric acid are

1. Homologous
2. Geometrical isomers
3. Enantiomers
4. Diastereomers.

✅ Correct Answer: 2

The process of separation of (dl)-mixture into its constituents is referred to as .

1. Fractional distillation
2. Resolution
3. Fragmentation
4. Sedimentation

✅ Correct Answer: 2

Which of the following compounds exhibit tautomerism ?

1. Cloroethane
2. Ethanol
3. Ethoxyethane
4. Nitroethane.

✅ Correct Answer: 1

The angle of rotation ofplane polarized light in polarimeter depends upon .

1. Cmnc. of the substance
2. Length of the tube
3. Nature ofthe substance
4. All of these

✅ Correct Answer: 4

The instrument used for measuring specific rotation is

1. Spectrometer
2. Polarimeter
3. Lactometer
4. Ammeter.

✅ Correct Answer: 2

Tartaric acid and meso-tartaric acid are .

1. Enantiomers
2. Diastereomers
3. Geometric isomers
4. None of these

✅ Correct Answer: 2

The energy difference between boat and chair conformations of cyclohexane is about

1. 150 kJ/mole
2. 30 kJ/mole
3. 12.5 kJ/mole
4. 50 kJ/mole

✅ Correct Answer: 2

Which of the following compound has chiral structure ?

1. 2-Metyylpentane
2. 23-Dimethylpentane
3. Isoamyl alcohol
4. Trimethylamine.

✅ Correct Answer: 2

cis-2-butene and trans-2-butene can be distinguished on the basis of

1. their hydrogenation products
2. their optical rotation
3. their ozonolysis products
4. their addition procucts with bromine.

✅ Correct Answer: 4

Which of the following can exhibit enantiomerism ?

1. cis-12-Dichlorocyclobutane
2. trans-12-Dichlorocyclobutane
3. cis-12-Dichlorocyclobutane
4. trans-13-Dichlorocyclobutan

✅ Correct Answer: 4