ORGANIC CHEMISTRY - 2 · 2015-06-25 · ORGANIC CHEMISTRY Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY...

$: ORGANIC CHEMISTRY - 2 · 2015-06-25 · ORGANIC CHEMISTRY Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY COACHING CIRCLE G:\Obj-Organic Chemistry Test-2.doc - 2 READ INSTRUCTIONS CAREFULLY$
Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY COACHING CIRCLE G:\Obj-Organic Chemistry Test-2.doc

ORGANIC CHEMISTRY - 2

READ INSTRUCTIONS CAREFULLY 1. The test is of 1 hour duration.

2. The maximum marks are 150.

3. This test consists of 50 questions. (Negative Marking)

4. For each question you will be awarded 3 marks if you have darkened only the bubble corresponding

to the correct answer and zero mark if no bubbles are darkened. Minus one (-1) mark will be

awarded for wrong answer

1. The treatment of CH3MgX with CH3 – C C – H produces:

a. CH4 b. CH3 – CH = CH2

c. CH3 – C C – CH3 d. CH3 – CH = CH – CH3

2. Correct order of m.p. is shown in :

a. neo-pentane > n-pentane > iso-pentane b. neo-pentane > iso-pentane > n-pentane c. iso-pentane > neo-pentane > n-pentane d. n-pentane > iso-pentane > neo-pentane

3. A, B and C, respectively are : a. b. c. d. 4. The hydrocarbon which cannot react with sodium in liquid ammonia is:

a. CH3 – CH2 – C C – CH2 – CH3 b. CH3 – CH2 – CH2 – C C – CH2 – CH2 – CH2 – CH3 c. CH3 – CH2 – C C – H d. CH3 – CH = CH – CH3

H3C

C = C H

H

CH3 ;

H3C

C = C H H

CH3

; CH3 CH2 CH2 CH3

H3C C = C

H H

CH3

;

H3C

C = C H

H

CH3 ; CH3 CH2 CH2 CH3

CH3 CH2 CH2 CH3 ;

H3C

C = C H

H

CH3 ;

H3C C = C

H H

CH3

H3C

C = C H

H

CH3 ; CH3 CH2 CH2 CH3 ;

H3C

C = C H H

CH3

CH3 C C CH3

Na/NH3/C2H5OH

H2/Pd –C/

H2/Ni2B

A

B

C

Dr. Sangeeta Khanna Ph.D


5. The reagent(s) for the following conversion is/are:

a. alcoholic KOH b. alcoholic KOH followed by NaNH2 c. aqueous KOH followed by NaNH2 d. Zn/CH3OH

6. Which of the following is not a good method for the conversion of CH3 – CH2 – CHO to CH3 –CH2 – CH3?

a. HI/Red P4 b. Zn – Hg/HCl

c. NH2NH2/KOH/glycol d.

SHCH

Ni/Hby follow ed SHHC

22|

2

7. a. b. c. d.

8. Zn/OH (ii) O )i( 23 A; A is:

a.

COOHCHCH

|

COOHCHCH

22

22

b.

CHOCHCH

|

CHOCHCH

22

22

c.

OHHCCHCH

|OHCHCHCH

222

222

d. all of these

9. C8H12 on ozonolysis followed by hydrolysis in the presence of Zn, produces one mole of each of

HCHO, CH3 – CO – CH3 and OCH – CH2 – CO – CH3. The compound is:

a. b. CH2 = CH – CH2 – C(CH3) = C(CH3)2 c. d. CH2 = C(CH3) – CH2 – C(CH3) = C(CH3)2

10. The number of optically active products obtained from the complete ozonolysis of the given compound

is:

a. 0 b. 1 c. 2 d. 4

Br

Br

? H H

KCOOΘ

KCOOΘ

Electrolysis , The Product is:

CH3 CH3

CH3 CH3

CH3 CH = CH C CH = CH C CH = CH CH3

CH3

H CH3

H



11. Among the following compounds which can be dehydrated very easily?

a. 2|

2223 H

OH

CCHCHCHCH b. CH3 – CH2 – CH2 – CHOH – CH3

c. 32

|

|23 CHCH

CH

OH

CCHCH

3

d. CH3 – CH2 – CH2 – CH2 – OH

12. Which of the following will not give ethane?

a. CH3 – CH2 – COONa + NaOH/CaO b. CH3 – CH2 – NH2 + HI/Red P

c. CH3 – CH2 – Mg – Br + CH3 – NH2 d. CH2 = CH2 + H2 K 373Pd/Pt

13. /OHΘ

A (major)

The major product ‘A’ is: a. b. c. d. 14. B.P. of CF4 (144 K) is much lower than that of n-hexane (341 K) although their molar masses are equal

(90 u). Which of the following is the correct explanation?

a. n-Hexane has saw teeth system b. Electronegativity of F-atom is extremely high c. CF4 has polar bonds d. n-Hexane has very high van der Waals’ forces

15. The correct decreasing order of enthalpy of combustion is shown in:

a. n-pentane > n-butane > isobtutane b. iso-butane > n-butane > n-pentane c. n-butane > iso-butane > n-pentane d. n-pentane > iso-butane > n-butane

16. On mixing a certain alkane with chlorine and irradiating it with UV light, it forms two monochloroalkane.

Which are optically inactive. This alkane would be:

a. neo-pentane b. propane c. pentane d. iso-pentane

17. Which branched chain isomer of the hydrocarbon with molecular mass 72 u gives only one isomer of monochloro substituted alkyl halide?

a. Tertiary butyl chloride b. neo-pentane c. iso-hexane d. neo-hexane

18. The major organic product of the reaction is:

AClCH

CH

CH

CCHK 353333

OHHC/KOH2

|

|3

52

3

3

a. A is 32|

2 CHCH

CH

CCH

3

b. A is 3|

3 CHCH

CH

CCH

3

c. A is CH3 – CH = CH – CH2 – CH3 d. no reaction

N(CH3)3



19. The correct order of reactivity of following alkenes for the reaction with H2 gas is:

a. b. c.

d. 20. CH3 – CH = CH2 reacts with HCl/(RCO)2O2.

The main intermediate is:

a. 33 CHHCCH

b. 223 HCCHCH

c. 33 CHHCCH

d. 223 HCCHCH

21. What is the major product of the addition of HCl on ?

a. b. c. d.

22. 3|

|

|3

?2

|

|3 CHH

CH

C

CH

OH

CCHCHCH

CH

CH

CCH

3

33

3

The reagent used is a. BH3 – THF, NaOH – H2O2 b. Hg(CH3COO)2, H2O, NaBH4 c. H2SO4, H2O d. H2O2/FeSO4

23. Which of the following statements is correct?

a. H.B.O. of unsymmetric alkene is always Anti-Markovnikov reaction b. O.M.D.M. of unsymmetric alkene is always Markovnikov reaction c. Reaction of H2O on alkene in the presence of H2SO4 is Markovnikov addition or rearrangement

addition d. All of the above

24. The final product of reaction of but-2-yne with chlorine water is:

a. 32

||

3 CHCCl

O

CCH b. 3

||||

3 CCl

O

C

O

CCH

c. 3||

3 CHCHCl

O

CCH d. all of these

H3C C = C

CH3

H3C CH3 > C = C

H3C CH3

H

>

CH3 H

C = C H3C CH3

H

> CH2 = CH2

H3C C = C

CH3

H3C CH3 < C = C

H3C CH3

H

<

H3C H

C = C H3C CH3

H

< CH2 = CH2

C = C H3C CH3

H

H3C H

C = C H3C CH3

H >

H3C C = C

CH3

H3C CH3 > CH2 = CH2

C = C H3C CH3

H

H3C H

C = C

H3C CH3

H

< H3C

C = C

CH3

H3C CH3 < CH2 = CH2

CH2 – CH2 – Cl CH CH3

Cl

Cl Cl



25. Which of the following will give red ppt. on reacting with R – C CH?

a. AgNO3/NH3 b. Cu2Cl2/NH3 c. Na/NH3 d. All of these

26. Which of the following shows electrophilic as well as nucleophilic addition reactions?

a. CH2 = CH2 b. CH CH c. CH3 – CH3 d. CH3 – CH = CH – CH3

27. The correct basic strength of CH3COO–, C6H5O–, OH–, R C C–,

Θ

2HN is:

a. CH3COO– < C6H5O– < OH– < 2

ΘΘ

HNCCR

b. 2356 NHOHCCRCOOCHOHC

c. COOCHOHCOHCCRNH 3562

d. OHNHCCRCOOCHOHC 2356

28. From the following reactions predict the correct order about acid strength.

HC CH + LiNH2 NH3 + HC CLi

NH3 + R–

2NH + RH

a. RH < NH3 < HC CH b. RH > NH3 > CH CH

c. RH > NH3 < HC CH d. RH < NH3 > HC CH 29. In the following reaction:

C7H8 CBAHCl/ZnFe/Br/Cl3 22

the compound ‘C’ is: a. m-bromotoluene b. o-bromotoluene

c. 3-bromo-2, 4, 6-trichlorotoluene d. p-bromotoluene 30. Which will undergo fastest SN2 substitution reaction when treated with NaOH?

a. Br

CH

H

CCH

3|

|25 b. Br

CH

CH

CCH

3

3

|

|3 c. Br

CH

HC

CH

3

52

|

| d. 322

|

|CHCHCH

H

Br

CH

31. Most stable carbocation is:

a. b. c. d. 32. Which one of the following alkylbromides undergoes most rapid solvolysis in methanol solution to give

corresponding methyl ether?

a. b. c. d.

CH3

+

+CH2 CH3

+

CH3

+

C

CH2

Br Br

Br

Br



33. In the conversion of ‘X’ is : a. H2/Pt b. Zn – Hg/HCl c. Li/NH3 d. NaBH4 34. The IUPAC names of is:

a. 3-ethyl-4,4-dimethylheptane b. 1, 1-diethyl-2, 2-dimethylpentane c. 4,4-dimethyl-5, 5-dimethylpentane d. 5, 5-diethyl-4, 4-dimethylpentane

35. Which of the following will react most easily with HBr?

a. b.

c. d. 36. Which of the following is correct order w.r.t. acidic character?

a. CH3 – CH2 – CHCl – COOH > CH3 – CHCl – CH2 – COOH > CH2Cl – CH2 – CH2 – COOH b. CH3 – CHCl – CH2 – COOH > CH3 – CH2 – CHCl – COOH > CH2Cl – CH2 – CH2 – COOH c. CH2Cl – CH2 – CH2 – COOH > CH3 – CH2 – CHCl – COOH > CH3 – CHCl – CH2 – COOH d. CH3 – CH2 – CHCl – COOH > CH2Cl – CH2 – CH2 – COOH > CH2 – CHCl – CH2 – COOH

37. The hyperconjuation stabilities of tert-butyl cation and 2-butene, respectively are due to:

a. p (empty) and * electron delocalisations b. * and electron delocalisations c. p (filled) and electron delocalisations d. p (filled) * and - * electron delocalisations

38. Enantiomer of is:

a. b.

CH2 = CH – CH2 – C – CH3

O

X

CH = CH – CH2 – CH

OH

CH3

O2N CH2OH CH2OH

CH3 CH2OH

H

Et

Me

Me

Br

H

HO

Br

H

Et

Br

Br

Me

H

Me

OH

H

Et

Br

Br

Me

H

Me

HO

H3CO CH2OH



c. d.

39. What is correct about isomerism for )I(

3

||

223 CH

O

CCHCHCH

)II(

3

||

|3 CH

O

CH

CH

CCH

3

)III(

32

||

23 CHCH

O

CCHCH

a. I and III are position isomers as well as metamers b. II and III are metamers

c. I and II are metamers d. All of the above

40. Which is the correct sequence of stability of the following enols? (Ph = C6H5)

a. 3

|||

3

||||||

OCH

O

CCH

OH

CCHH

O

CCH

OH

CPhPh

O

CCH

OH

CPh

b. Ph

O

CCH

OH

CPhH

O

CCH

OH

CPhCHO

O

CCH

OH

CCH||||||

3

|||

3

c. Ph

O

CCH

OH

CPhOCH

O

CCH

OH

CCHH

O

CCH

OH

CPh|||

3

|||

3

|||

d. 3

|||

3

||||||

CHO

O

CCH

OH

CCHPh

O

CCH

OH

CPhH

O

CCH

OH

CPh

41. The Z-isomer is:

a.

7325 HCCCH

HCH||

b.

I

||

CBr

ClCF

c.

Br

||

C I

ClCH

d.

5237 HC CCH

HCCCH

||523

42. In the Newman projection for 2,2-dimethylbutane, . What are ‘X’ and ‘Y’?

a. H and H b. H and C2H5 c. C2H5 and H d. CH3 and CH3

Et

Me

Br

Br

H

H

OH

Me

Et

Me

Br

Br

H

Me

H

HO

CH3

Y

H H

H3C

X



43. Which of the following is correct for the reactions? a. A and B form a racemic mixture

b. C and D form a racemic miture c. A, B, C and D all are the same compound d. A and B are the same compounds while C and D are different compounds

44. Which of the following is not correct for SN1 mechanism?

a. Order of reactivity of halide is CH3 > 1° > 2° > 3° b. Rate [substrate] c. Reaction is favoured by polar solvent

d. Only 50% inversion takes place for an optically active d or compound

45. Which of the following does not show geometrical isomerism?

a. 1, 2-Dichloropent-1-ene b. 1, 3-Dichloropent-1-ene c. 1, 1-Dichloropent-1-ene d. 1, 4-Dichloropent-2-ene

46. Which of the following is strongest nucleophile

a. 3

Θ

HC b. 2

Θ

HN c. HOΘ

d. HCCHΘ

2

47. The nubmer of steroisomers and optically active isomers possible for the compound ,

are respectively:- a. 3, 2 b. 3, 3 c. 4, 4 d. 2, 2

48. Electrolytic Redcution of nitrobenzene is strongly acidic medium will form

a. Aniline b. p-Amino phenol c. nitrosobenzene d. Hydrazobenzene

49. Number of stereocentres and stereisomers of the given compound

a. 1 & 2 b. 2 & 4 c. 3 & 8 d. zero, 2

50. (CH3)2C = CH2 + (CH3)3CH 42SOH?

The main product is:

a. 322|

3 CHCHCHCH

CH

CCH

3

b. 3

|

2|

|

3 CHH

CH

CCH

CH

CH

CCH

3

3

3

c. CH3 – (CH2)6 – CH3 d. no reaction

H3C

C = C

CH3

H H + Br2 A + B

(X)

H3C

C = C CH3

H

H + Br2 C + D

(Y)

Cl

CH3

y

x

C – C

z

x

y

z



ORGANIC CHEMISTRY -2 (ANSWERS)

1. A

Sol. CH3 – C C – H + CH3MgX CH4 + CH3 – C C – MgX

2. A

Sol. Branching decreases m.p., but symmetry increases m.p. due to better packing

3. D

4. D

Sol. Na/NH3 cannot reduce C = C double bond. ‘a’ and ‘b’ produce trans-alkenes while ‘c’ works acidically

where H of – C C – H is replaced by Na

5. B

Sol.

6. B

Sol. Zn – Hg/HCl reduction method of carbonyl compounds is called Clemmensen method

7. D

Sol.

At anode Triple bond is not possible in cyclic system 8. B

Sol. Ozonolysis of

CH

HC||

followed by hydrolysis using zinc supplies ‘O’ atoms to double bonded C-atoms

and cleaves this bond. 9. B Sol.

10. A 11. C Sol. It is 3° alcohol that gives 3° carbocation which is easily formed. 12. B Sol. Only CH3 – CH2 – NH2 does not give CH3 – CH3 directly on reacting with HI

Br

Br

KOH (alc.)

H2C = CH – Br

NaNH2 CH = CH

K OCΘ

K OCΘ

O

O

2K+

+

Θ

OC

O

O

Θ

OC

Θ

OC

O

O

Θ

OC

C

C

O

O

O

-2CO2 Two units

C = O, OCH – CH2 – C = O and O = C

H

H CH3

CH3

CH3

can be obtained by the ozonolysis of H2C = CH – CH2 – C = C – CH3

CH3 CH3



13. B Sol.

14. D 15. A 16. B 17. B 18. B

Sol.

product) Say tzef f(3

|

332

|

32

|

|3

Cl

KOH/.Alc3

|

|3 CHCH

CH

CCHCHCH

CH

CCHHC

CH

CH

CCHClCH

CH

CH

CCH

333

3

3

3

19. B 20. C Sol. Peroxide effect is for addition of HBr on unsymmetric alkene

ClCHHCCHHClCHCHCH 3333

21. C Sol. 22. C 23. D 24. A 25. B 26. B

Sol. C C bond undergoes electrophilic as well as nucleophilic addition reaction 27. A

Sol. Acid strength is CH3COOH > C6H5OH > HOH > R – C CH > NH3. So, basis strength order of related

nuelophiles is CH3COO– < C6H5O– < OH– < R – C C– < NH

2

28. A

Sol. From 1st equation HC CH is more acidic than NH3 From 2nd equation, NH3 is more acidic than RH (Acid being produced is weaker than the one that produces it)

Acidic strength HC CH > NH3 > RH or RH < NH3 < HC CH 29. A

Sol.

30. D 31. C 32. A 33. D 34. A

Sol.

ptanedimethy lhe-4 ,4Ethy l3

3

1

2

2

|

3|

|

4

2

5

2

6

3

7

HCHCH

CH CH

C

CH

CH

CHCHCHC

3 2

3

3

N(CH3)3 H2C

H

/OH

Θ

+ H2O + N(CH3)3

CH = CH2

H+

CH = CH2

H

CH2 – CH3

3° Cl

– Cl

CH3

3Cl2/

Sunlight

CCl3

Br2/Fe

CCl3

Br

Zn/HCl

Br

CH3



35. C

Sol. +I effect of CH3 increases the basic character of OH group and makes its reaction easier with HBr.

36. A Sol. Cl has – I effect and increase acidic character. Moreover, closer is its position COOH group, stronger is

the acid. 37. A

Sol.

3

3

3

3

CH

CH

C

H

CHp)(empty

CH

CH

C

H

CH|

|2

|

|

|

2

38. A Sol.

39. D

40. A 41. B

Sol.

isomerZ

17||

9

5335 I C Br

ClCF

42. B, D

Sol. 52

3

3HCY

32

|

|

2

HX

3

1

CHCH

CH

CH

CHC

3

3

33 CHX

32

3|

|

2

CHY

3 CHHC

CH

CH

CCH

43. A Sol. X is cis and Br2 has anti-attack. The product has to be a racemic mixture Y is trans and anti-attack of Br2 gives meso compound i.e., C and D are same compound 44. A 45. C 46. A 47. A 48. B 49. C 50. B

Sol. 3

|

2

|

|3

CH

CH

CCH|

|3

H2

|3 CH

CH

CCH

CH

CH

CCH

CH

CH

CCHCH

CH

CCH

33

3

3

3|

2

3

33

HCCH

3

|

|2

|

|3

|

|3 3CH

3CH

|

|3

3

3

3

3

3

3

CH

CH

CH

CCH

CH

CH

CCH

CH

CH

CCH

H2C

H

C

H

CH CH3

* H2C

C CH CH3 H

H

H

Et

Me

Me

Br

H

HO

Br

H

Et

Br

Br

Me

H

Me

HO

Et

Me

Br

Br

H

Me

H

HO

ORGANIC CHEMISTRY - 2 · 2015-06-25 · ORGANIC CHEMISTRY Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY...

Documents

Transcript of ORGANIC CHEMISTRY - 2 · 2015-06-25 · ORGANIC CHEMISTRY Dr. Sangeeta Khanna Ph.D 1 CHEMISTRY...