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Exercise - I

OBJECTIVE TYPE QUESTIONS

Multiple choice questions with ONE option correct

1. The IUPAC name for the compound

3 3CH CH CH CHCH|C CH

(a) 4-Ethyl-2-pentane (b) 1-Ethyl-3-methyl-2-butane

(c) 3-Methylhex-4-en-1-yne (d) 4-Methyl-2-hexen-5-yne

2. The correct IUPAC name of the compound

O

(a) Pent-4-en-2-one (b) 3-Buten-1-al

(c) 3-Acetyl propene-1 (d) Formyl Propene

3. The correct IUPAC name of the compound

CH3CH2C – CH2

OH

CH3

(a) ter-pentanol cyclo propane (b) 2-Cyclobutylbutan-2-ol

(c) 1-Cyclopropyl-2-methylbutan-2-ol (d) 2-Cyclobutylbutan-2-ol

4. The correct IUPAC name of the acrolein is

(a) prop-2-enal (b) cyanomethane

(c) methanenitrile (d) cyanoethane

5. The IUPAC name of the compound

CH3CH2NH

CH = O is

(a) aldoethanamine (b) N-Formyl aminoethane

(c) ethyl formylamine (d) N-Ethyl methanamide

6. A student named a certain compound as 2, 3-diethyl butane. Its correct IUPAC name

is

(a) 2, 3-dimethyl hexane (b) 3, 4-Dimethyl hexane

(c) 2-Ethyl-3-methyl pentane (d) 2-Ethyl-butane

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7. The IUPAC name of 3 2Cl CCH CHO is

(a) chloral (b) trichloropropanal

(c) 1, 1, 1-trichloropanal (d) 3, 3, 3-trichloropropanal

8. The principal functional group of following compound is

2 2 2 2

OH O| ||

ClCH CH CH C CH NO

(a) nitro (b) alcohol (c) alkyl halide (d) ketnone

9. The correct IUPAC name of

CH3CH2 – C – CH – CH2

CH2H

CH2Cl

(a) 1-Chloro-2-butyl cyclo propane (b) 1-Chloro-2-cyclopropyl butane

(c) 1-Chloromethyl-1-ethyl cyclo propane

(d) 3-Chloromethyl-1, 2-methylene pentane

10. The IUPAC name of the compound is

(a) bicycle [2.1.0] pentane (b) 1, 2-cyclopropylcyclobutane

(c) cyclopentane (4, 3) annulene (d) 1, 2-methylnecyclobutane

11. The name of

2

CH CH| |CHO NH

is

(a) 1-emino prop-2-enal (b)3-amino prop-2-enal

(c) 1-amino-2-formylthene (d)3-emino-1-oxoprop-2-ene

12. The IUPAC name of the compound

Cl

CH3

C=C

CH2CH3

I is

(a) trans-2-chloro-3-iodo-2-pentene (b) cis-2-chloro-3-iodo-2-pentane

(c) trans-3-iodo-4-chloro-3-pentene (d) cis-3-iodo-4-chloro-3-pentene

13. Heterolytic cleavage of a carbon-carbon bond produces

(a) two carbonium ions (b)two free radicals

(c) one cation and one anion (d)a free radical and carbanion

14. What is the state of hybridization of carbon in carbanion ?

(a) sp (b) sp2 (c) sp

3 (d) sp

2d

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15. Mark the odd reagent amongst the following

(a) CN (b) . .

3. .

CH O H (c) . .

3NH (d) 3SO

Multiple choice question with ONE or MORE THAN ONE option correct

1. Which of the following species is / are electrophilic ?

(a) 3SO (b) 3AlCl (c) 3NH (d) 3 3CH OCH

2. Which of the following free radicals is / are resonance stabilized

(a) Vinyl (b) Allyl (c) iso-Propyl (d) Benzyl

3. Heterolytic cleavage of a C – X bond may result in the formation of

(a) a free radical (b) a carbocation (c) a carbine (d) a carbanion

4. Which of the following pairs of compounds are homologous ?

(a) 1-Propanol and 2-propanol (b) 1-Propanol and 1-butanol

(c) 2-Propanol and 2-methyl-2-propanol (d) Ethanal and propanal

5. Which of the following is (are) unsaturated compounds ?

(a) Benzene (b) Hexane (c) Cyclohexane (d) Propene

6. Resonance structures of a molecule should have

(a) identical arrangements of atoms (b) nearly the same energy content

(c) the same number of paired electrons (d) identical bonding

7. Phenol is less acidic than:

(a) acetic acid (b) p-methoxyphenol (c) p-nitrophenol (d) ethanol

8. Isovalent hyperconjugation explains the stability of

(a) Carbocations (b) Carbanions (c) Free radicals (d) Carbenes

9. Homolytic fission yields

(a) Electrophiles (b)Nucleophiles (c)Freeradicals (d)Electrophiles and nucleophiles.

10. Which of the following species contain six electrons around the central carbon atom?

(a) Carbanion (b) Carbocation (c) Carbene (d) Free radical

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69

Exercise - II

ASSERTION & REASON , COMPREHENSIVE & MATCHING TYPE

Assertion and Reason

(a) If both A and R are true and R is the correct explanation of A.

(b) If both A and R are true but R is not the correct explanation of A

(c) If A is true but R is false.

(d) If A is false but R is true.

1. A : CO is a good reducing agent.

R : CO is a combustible gas

2. A : Carbonic acid is a dibasic acid

R : Carbon monoxide when dissolved in water yields carbonic acid

3. A : Silicon carbide is a very hard carbide

R : Silicon carbide is a covalent hydride.

4. A : Carbon exhibits catenation to maximum extent

R : Valency of carbon is 4.

5. A : Ethane and propane are homologues.

R : Ethane and propane are both alkanes.

Passage based questions

Passage-1

There is another class of intermediate called carbine. There are also radical anion and

radical cation formed by addition and removal of an electron from the p-bond system.

1. Which is not the carbene out of the following?

(a) : CH2 (b) :CCl2 (c) :C

Br

Cl (d) CCl3

2. Singlet carbene and triplet carbene differ in :

(a) number of s-bonds (b) number of unshared electron

pairs

(c) number of hybrid orbitals (d) type of

hybridization

3. Consider following structures of A and B.

H

H C 1.12Å

103°

:CH2

136°

CH2

C H

H

1.03 Å

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Select correct statement about (A) and (B) :

(a) (A) represents singlet and (B) represents triplet carbenes

(b) (A) resembles carbocation and is less stable than (B) which is a free diradical

(c) Non-bonding electron repulsions in A and B are identical

(d) All of the above are correct statements.

Passage-2

The reaction of an electrophile with a nucleophile is the same as the reaction of a Lewis

acid with a Lewis base and is termed as Lewis acid-base association reaction, as a result

of which each atom in the product completes its octet (except H which complets its

duplet).

1. Consider following reaction between an electrophile and nucleophile :

3

3

. .|

3 2|

CH

H C – C H O :

CH

3|

3|

3

CH

H C — C — OH H

CH

Incorrect statement(s) is/are

(a) It is a Lewis acid-base association reaction

(b) It is Lowry-Bronsted acid-base reaction

(c)

atoms in the product

(d) A is an electrophile and B is a nucleophile

2. In which case additional reagent is required to generate an electrophile?

(a) CH=CHCH2 CH=CHCH2Br

(b) CH=CHCH2 CHCHCH3

Br Br

(c) CH=CHCH2 CHCHCH2

Br

(d) In all cases

3. Which is not the correct increasing order of the property indicated?

(a) – –3 3 2 3CH OH CH CO CH O (base strength and nucleophile strength)

(b) –F Cl Br I (base strength and nucleophile strength)

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(c)

CH3 CH3CH3

(stability of free radicals)

(d)

Cl

Cl

Cl

Cl

Cl

Cl (dipole moment)

Matching Type Questions

1. Match the following :

List –I List – II

(A) R X Y R Y X (1) Elimination

(B) 2 2 2RCH CH X RCH CH HX (2) Condensation

(C) 3 3 3 2 2 3

3

CH CH CH CH CH CH CH|CH

(3) Substitution

(D) 2 2RCH O H A RCH A H O (4) Rearrangement

2. Match the following :

List –I List – II

(A)

3

3

CH C H|CH

(1) Free radical

(B) A . . A A A (2) Carbene

(C) 2 2 2 2CH N CH N (3) Benjyne

(D) C6H4 (4) Carbocation

(a) A-4, B-3, C-1, D-2 (b) A-4, B-1, C-2, D-3

(c) A-1, B-4, C-3, D-2 (d) A-1, B-4, C-3, D-2

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72

Exercise - III

SUBJECTIVE TYPE

1. Why does carbon exhibit catenation to maximum extent ?

2. How many alkyl groups are possible for C4H9 ?

3. What types of reagents are produced by heterolytic cleavage of bonds ?

4. Why inductive effect is called transmission effect ?

5. Give two differences between inductive effect and electromeric effect.

6. What is + E effect ? Give one example.

7. Name the kind of effect that operates to explain the stability of carbocations.

8. What is singlet carbine and triplet carbine ?

9. Classify the following species into electrophiles and nucleophiles.

SO3, BF3, H2O, –OH

10. Why hyperconjugation is called no bond resonance ?

11. Classify the following into electrophilic and nucleopilic reagents ?

(i) Cl (ii)

2N O (iii) CN (d) . .

. .R O H

12. Discuss the mechanism of addition of chlorine in CCl4 to ethane ?

13. Explain,

(i) Secondary amine is more basic than primary amine

(ii) - -chloro propionic acid.

14. Explain

(i) Ethene is more reactive than propene

(ii) Formic acid is more acidic than acetic acid

15. Write the IUPC names of the following conjugation

(i) 3 2 2(CH ) C CH (ii) 3 2 2 2(CH ) CH CH CH Cl

(iii) 3 3(CH ) COH (iv) 2 2HOH C CH CH CH OH

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(v) 3 2 2 3 2(CH ) CHCH CH(CH ) (vi) 2 2 2

3

H C C CH CH OH|CH

(vii) 2 2HC C CH CH CH CHO

|Cl

16. Write the structural formulae

(i) But-3-en-1-ol

(ii) 2-Aminoethanol

(iii) 2-Chloro-3-methylbutane

(iv) Octa-3, 5-diene

(v) 4-Ethyl-5-methyl-2-hexene

17. Write the IUPAC names of the following

(i) 3 2 2 3(CH ) CHCH CH

(ii) 2 5 2 3(C H ) CHCH

(iii) 3 2 3 2(CH ) CHCH(CH )

(iv) 3 2 2 2(CH ) C(Br)CH CH Br

18. Are the following names correct in IUPAC system ? If not write the correct names.

(i) Pent-3-yne

(ii) 4, 4, 3-Trimethyl-hex-1-yne

(iii) Hexa-1, 6-diene

19. Give IUPAC names of the following

(i) CH2CHO

(ii)

CH3 – CH – CH – COOH

CH3 CH3

(iii)

CH3 – CH – CH2Cl

CH3 (iv)

CH3 – C – CH3

CHO

CH3

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(v)

CH2

CH2

CH2

CH2

C

CH

CH2 – CH3

(vi)

H2C

HC

CH

CH

CH2

CH2

OH

(vii)

H3CCH3

O

(viii)

CH3 – CH – CHO

(ix)

C6H5 – C – CH – CH3

OH

C2H5

(x) 3 2 3 2(CH ) C(CCl )

(xi)

Me

Me

Me

Me

Me

Me is methyl group (xii)

Me

Me

Me

COOH

Me

E is ethyl group

(xiii) 2 2ClCH CH COCl (xiv) 3 2 2 5(CH ) CHCOOC H

20. Give IUPAC name of the following compounds

(i) C6H5 – C(CH3)2

OH

(ii) CH3 – CH – CO – CH – CH3

CH3 CH3

(iii) CH3 – C – CH2 – C – CH3

C2H5 C2H5

NO2 Br

(iv) CH3 – C – CH2 – C – CH3

C2H5 C2H5

F Cl

(v) CH3 – CH – CH2 – COOC2H5

CH3

(vi) CH3 – CH2 – C – CH – CH2Cl

CH3

Br Br

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(vii)2 5 2(C H ) CH CHO

(viii) CH3 – CH – CH – C = CH2

CH2CH3

Cl

(ix) CH3CH2 – C – N – CH3

O CH3 (x)

CH3 – CH – C – Cl

CH3

*****

Exercise - IV

IIT – JEE PROBLEMS

1. Arrange the following in:

(i) Increasing reactivity towards HCN

CH3CHO, CH3COCH3, HCHO, C2H5COCH3

(ii) n-butane, n-butanol, n-butyl chloride, isobutane in increasing order of boiling

point.

(iii) Increasing order of acid strength:

ClCH2COOH (I), CH3CH2COOH (II)

ClCH2CH2COOH (III), (CH3)2CHCOOH (IV), CH3COOH (V)

(iv) Increasing reactivity in nucleophilic substitution reactions

CH3F, CH3I, CH3Br, CH3Cl

2. Write the IUPAC name of:

(i) CH3CH2CH = CHCOOH

(ii) Give the IUPAC name of the following compound:

Me

Me Me

Me

Me

(iii) Write the IUPAC name for the following:

CH3

N

CH3

CH3

C2H5CH3

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3. Give reasons for the following:

(i) Carbon oxygen bond lengths in formic acid are 1.23 o

A and 1.36o

A and both the

carbon oxygen bonds in sodium formate have the same value i.e. 1.27o

A .

(ii) Phenyl group is known to exert negative inductive effect. But each phenyl ring

in biphenyl (C6H5–C6H5) is more reactive than benzene towards electrophilic

substitution.

(iii) Aryl halides are less reactive than alkyl halides towards nucleophilic reagents.

(iv) CH2=CH– is more basic than HC C .

(v) Normally, benzene gives electrophilic substitution reaction rather than

electrophilic addition reaction although it has double bonds.

4. Write the structural formula of 4-chloro-2-pentene.

5. Discuss the hybridization of carbon atoms in allene (C3H4) and show the orbital

overlaps.

6. Which one is more soluble in diethyl ether – anhydrous 3AlCl or hydrous

3AlCl ?

Explain in terms of bonding?

7. Match the Ka values

Ka

(a) Benzoic acid 3.3 10–5

(b) O2N COOH

10.2 10–5

(c) Cl COOH

30.6 10–5

(d) H3CO COOH

6.4 10–5

(e) CH3 COOH

4.2 10–5

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8. CH3

OH

CH2

Write resonance structure of the given compound.

9. Which of the following is more acidic and why?

H3N H3N F,

10. (i) obs = i i

i

x

Where i is the dipole moment of stable conformer of the molecule. Z–CH2–

CH2–Z and xi is the mole fraction of the stable conformer.

Given: obs = 1.0 D and x (Anti) = 0.82

Draw all the stable conformers of Z–CH2–CH2–Z and calculate the value of

Gauche.

(ii) Draw the stable conformer of Y–CHD–CHD–Y (meso form), when Y = CH3

(rotation about (C2–C3) and Y = OH (rotation about C1–C2) in Newmann

projection.

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