Question Bank: Organic Chemistry : Some Basic Principles & Techniques | Chemistry Class 11 - NEET PDF Download

 Page 1


 
 
Tetravalence of Carbon : Shapes of 
Organic Compounds 
1. The number of sigma ( ?) and pi ( ?) bonds in pent- 
2-en-4-yne is 
(a) 13 ? bonds and no ? bond 
(b) 10 ? bonds and 3 ? bonds 
(c) 8 ? bonds and 5 ? bonds 
(d) 11 ? bonds and 2 ? bonds. (NEET 2019) 
2. Which of the following molecules represents the 
order of hybridisation sp
2
, sp
2
, sp, sp from left to 
right atoms? 
(a) HC C — C CH 
(b) CH 2 CH — C CH 
(c) CH 2 CH — CH CH 2 
(d) CH 3 — CH     CH — CH 3 (NEET 2018) 
3. The total number of p-bond electrons in 
the following structure is 
(a) 12 (b) 16 (c)  4 (d) 8 
(2015, Cancelled) 
4. The state of hybridisation of C 2, C 3, C 5 and C 6 of the 
hydrocarbon, 
(a) sp, sp
2
, sp
3 
(b) sp
3
, sp
2
, sp 
(c)  sp
2
, sp, sp
3 
(d) sp, sp
3
, sp
2 
(2008) 
6. In which of the following compounds there is more 
than one kind of hybridisation (sp, sp
2
, sp
3
) for 
carbon?         
(a) CH2 CH – CH   CH 2 
(b) H – C C – H 
(c) CH 3CH 2CH 2CH 3 
(d) CH 3 – CH     CH – CH 3 
(1995) 
7. A straight chain hydrocarbon has the molecular 
formula C 8H 10. The hybridisation of the carbon 
atoms from one end of the chain to the other are 
respectively sp
3
, sp
2
, sp
2
, sp
3
, sp
2
, sp
2
, sp and sp. The 
structural formula of the hydrocarbon would be 
(a) CH 3C      CCH 2 – CH     CHCH   CH 2 
(b) CH 3CH 2 – CH    CHCH    CHC    CH 
(c) CH 3CH     CHCH 2 – C      CCH   CH 2 
(d) CH 3CH CHCH 2 – CH CHC CH (1991) 
8. Which of the following possesses a sp-carbon in 
its structure? 
(a) CH 2 CCl – CH CH 2 
(b) CCl 2 CCl 2 (c)  CH 2 C CH 2 
(d) CH 2 CH – CH CH 2 
(1989) 
9. The Cl–C–Cl angle in 1, 1, 2, 2-tetrachloro-
ethene and tetrachloromethane respectively will be 
about 
CH
3
 CH
3
 
(a)  120° and 109.5° (b) 90° and 109.5° 
(c)  109.5° and 90° (d) 109.5° and 120° 
CH
3 
– C – CH CH – CH – C CH (1988) 
7 6 
5 4 3 2 1 
CH
3
 
is in the following sequence 
(a) sp
3
, sp
2
, sp
2 
and sp (b) sp, sp
2
, sp
2 
and sp
3
 
Classification of Organic Compounds 
10. An  organic   compound   X(molecular   formula   
C H O N) has six carbon atoms in a ring system, 
(c) sp, sp
2
, sp
3 
and sp
2 
(d) sp, sp
3
, sp
2 
and sp
3
 6 7 2 
5. In the hydrocarbon, 
CH
3 
– CH CH– CH
2
– C CH 
(2009) 
two double bonds and a nitro group as substituent, 
X is 
(a) homocyclic but not aromatic 
6 5 4 3 2 1 (b) aromatic but not homocyclic 
the state of hybridisation of carbons 1, 3 and 5 are in 
the following sequence 
(c) homocyclic and aromatic 
(d) heterocyclic and aromatic. (1990) 
12.2 
12.4 
Page 2


 
 
Tetravalence of Carbon : Shapes of 
Organic Compounds 
1. The number of sigma ( ?) and pi ( ?) bonds in pent- 
2-en-4-yne is 
(a) 13 ? bonds and no ? bond 
(b) 10 ? bonds and 3 ? bonds 
(c) 8 ? bonds and 5 ? bonds 
(d) 11 ? bonds and 2 ? bonds. (NEET 2019) 
2. Which of the following molecules represents the 
order of hybridisation sp
2
, sp
2
, sp, sp from left to 
right atoms? 
(a) HC C — C CH 
(b) CH 2 CH — C CH 
(c) CH 2 CH — CH CH 2 
(d) CH 3 — CH     CH — CH 3 (NEET 2018) 
3. The total number of p-bond electrons in 
the following structure is 
(a) 12 (b) 16 (c)  4 (d) 8 
(2015, Cancelled) 
4. The state of hybridisation of C 2, C 3, C 5 and C 6 of the 
hydrocarbon, 
(a) sp, sp
2
, sp
3 
(b) sp
3
, sp
2
, sp 
(c)  sp
2
, sp, sp
3 
(d) sp, sp
3
, sp
2 
(2008) 
6. In which of the following compounds there is more 
than one kind of hybridisation (sp, sp
2
, sp
3
) for 
carbon?         
(a) CH2 CH – CH   CH 2 
(b) H – C C – H 
(c) CH 3CH 2CH 2CH 3 
(d) CH 3 – CH     CH – CH 3 
(1995) 
7. A straight chain hydrocarbon has the molecular 
formula C 8H 10. The hybridisation of the carbon 
atoms from one end of the chain to the other are 
respectively sp
3
, sp
2
, sp
2
, sp
3
, sp
2
, sp
2
, sp and sp. The 
structural formula of the hydrocarbon would be 
(a) CH 3C      CCH 2 – CH     CHCH   CH 2 
(b) CH 3CH 2 – CH    CHCH    CHC    CH 
(c) CH 3CH     CHCH 2 – C      CCH   CH 2 
(d) CH 3CH CHCH 2 – CH CHC CH (1991) 
8. Which of the following possesses a sp-carbon in 
its structure? 
(a) CH 2 CCl – CH CH 2 
(b) CCl 2 CCl 2 (c)  CH 2 C CH 2 
(d) CH 2 CH – CH CH 2 
(1989) 
9. The Cl–C–Cl angle in 1, 1, 2, 2-tetrachloro-
ethene and tetrachloromethane respectively will be 
about 
CH
3
 CH
3
 
(a)  120° and 109.5° (b) 90° and 109.5° 
(c)  109.5° and 90° (d) 109.5° and 120° 
CH
3 
– C – CH CH – CH – C CH (1988) 
7 6 
5 4 3 2 1 
CH
3
 
is in the following sequence 
(a) sp
3
, sp
2
, sp
2 
and sp (b) sp, sp
2
, sp
2 
and sp
3
 
Classification of Organic Compounds 
10. An  organic   compound   X(molecular   formula   
C H O N) has six carbon atoms in a ring system, 
(c) sp, sp
2
, sp
3 
and sp
2 
(d) sp, sp
3
, sp
2 
and sp
3
 6 7 2 
5. In the hydrocarbon, 
CH
3 
– CH CH– CH
2
– C CH 
(2009) 
two double bonds and a nitro group as substituent, 
X is 
(a) homocyclic but not aromatic 
6 5 4 3 2 1 (b) aromatic but not homocyclic 
the state of hybridisation of carbons 1, 3 and 5 are in 
the following sequence 
(c) homocyclic and aromatic 
(d) heterocyclic and aromatic. (1990) 
12.2 
12.4 
 
Nomenclature of Organic Compounds 
15. The correct IUPAC name for the compound 
11. The IUPAC name of the compound 
(a) 5-formylhex-2-en-3-one 
(b) 5-methyl-4-oxohex-2-en-5-al 
(c) 3-keto-2-methylhex-5-enal 
(d) 3-keto-2-methylhex-4-enal (NEET 2017)
12. The structure of isobutyl group in an organic 
compound is 
(a) CH 3 —CH 2 —CH 2 —CH 2 — 
(b) 
(c) 
is 
(a) 4-ethyl-3-propylhex-1-ene 
(b) 3-ethyl-4-ethenylheptane 
(c) 3-ethyl-4-propylhex-5-ene 
(d) 3-(1-ethylpropyl)hex-1-ene. (2011) 
16. The IUPAC name of the following compound is 
(a) trans-2-chloro-3-iodo-2-pentene 
(b) c is-3-iodo-4-chloro-3-pentane 
(c) trans-3-iodo-4-chloro-3-pentene 
(d) c is-2-chloro-3-iodo-2-pentene. 
(Mains 2011, 1998) 
17. The IUPAC name of the compound 
(d) (NEET 2013) 
13. Structure of the compound whose IUPAC name is 
3-ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid 
is 
(a) (b) 
CH 3CH CHC CH is 
(a)  pent-4-yn-2-ene (b)  pent-3-en-1-yne 
(c)  pent-2-en-4-yne (d)  pent-1-yn-3-ene. 
(Mains 2010) 
18. The IUPAC name of the compound having the 
formula CH C—CH CH 2 is 
(a) 1-butyne-3-ene (b) but-1-yne-3-ene 
(c)  1-butene-3-yne (d) 3-butene-1-yne. 
(c) (d) 
 
(NEET 2013) 
19. The IUPAC name of is 
(a) 1-chloro-1-oxo-2,3-dimethylpentane 
(b) 2-ethyl-3-methylbutanoyl chloride 
(2009) 
14. Which nomenclature is not according to IUPAC 
system? 
(a) Br – CH 2 – CH CH 2 
1-Bromoprop-2-ene 
CH 3 
(b) CH 3 – CH 2 – C – CH 2 – CHCH 3 
(c) 2,3-dimethylpentanoyl chloride 
(d) 3,4-dimethylpentanoyl chloride. (2006) 
20. Names of some compounds are given. Which one is 
not in IUPAC system? 
(a) 
Br CH 3 
(c) 
4-Bromo-2,4-dimethylhexane 
CH3 – CH – CH – CH 2 CH 3 
CH3 
2-Methyl-3-phenylpentane 
(b) 
(c) 
(d) CH3 – C – CH2 – CH2 – CH 2 COOH 
O 
5-Oxohexanoic acid 
(d) (2005) 
12.5 
(2012) 
Page 3


 
 
Tetravalence of Carbon : Shapes of 
Organic Compounds 
1. The number of sigma ( ?) and pi ( ?) bonds in pent- 
2-en-4-yne is 
(a) 13 ? bonds and no ? bond 
(b) 10 ? bonds and 3 ? bonds 
(c) 8 ? bonds and 5 ? bonds 
(d) 11 ? bonds and 2 ? bonds. (NEET 2019) 
2. Which of the following molecules represents the 
order of hybridisation sp
2
, sp
2
, sp, sp from left to 
right atoms? 
(a) HC C — C CH 
(b) CH 2 CH — C CH 
(c) CH 2 CH — CH CH 2 
(d) CH 3 — CH     CH — CH 3 (NEET 2018) 
3. The total number of p-bond electrons in 
the following structure is 
(a) 12 (b) 16 (c)  4 (d) 8 
(2015, Cancelled) 
4. The state of hybridisation of C 2, C 3, C 5 and C 6 of the 
hydrocarbon, 
(a) sp, sp
2
, sp
3 
(b) sp
3
, sp
2
, sp 
(c)  sp
2
, sp, sp
3 
(d) sp, sp
3
, sp
2 
(2008) 
6. In which of the following compounds there is more 
than one kind of hybridisation (sp, sp
2
, sp
3
) for 
carbon?         
(a) CH2 CH – CH   CH 2 
(b) H – C C – H 
(c) CH 3CH 2CH 2CH 3 
(d) CH 3 – CH     CH – CH 3 
(1995) 
7. A straight chain hydrocarbon has the molecular 
formula C 8H 10. The hybridisation of the carbon 
atoms from one end of the chain to the other are 
respectively sp
3
, sp
2
, sp
2
, sp
3
, sp
2
, sp
2
, sp and sp. The 
structural formula of the hydrocarbon would be 
(a) CH 3C      CCH 2 – CH     CHCH   CH 2 
(b) CH 3CH 2 – CH    CHCH    CHC    CH 
(c) CH 3CH     CHCH 2 – C      CCH   CH 2 
(d) CH 3CH CHCH 2 – CH CHC CH (1991) 
8. Which of the following possesses a sp-carbon in 
its structure? 
(a) CH 2 CCl – CH CH 2 
(b) CCl 2 CCl 2 (c)  CH 2 C CH 2 
(d) CH 2 CH – CH CH 2 
(1989) 
9. The Cl–C–Cl angle in 1, 1, 2, 2-tetrachloro-
ethene and tetrachloromethane respectively will be 
about 
CH
3
 CH
3
 
(a)  120° and 109.5° (b) 90° and 109.5° 
(c)  109.5° and 90° (d) 109.5° and 120° 
CH
3 
– C – CH CH – CH – C CH (1988) 
7 6 
5 4 3 2 1 
CH
3
 
is in the following sequence 
(a) sp
3
, sp
2
, sp
2 
and sp (b) sp, sp
2
, sp
2 
and sp
3
 
Classification of Organic Compounds 
10. An  organic   compound   X(molecular   formula   
C H O N) has six carbon atoms in a ring system, 
(c) sp, sp
2
, sp
3 
and sp
2 
(d) sp, sp
3
, sp
2 
and sp
3
 6 7 2 
5. In the hydrocarbon, 
CH
3 
– CH CH– CH
2
– C CH 
(2009) 
two double bonds and a nitro group as substituent, 
X is 
(a) homocyclic but not aromatic 
6 5 4 3 2 1 (b) aromatic but not homocyclic 
the state of hybridisation of carbons 1, 3 and 5 are in 
the following sequence 
(c) homocyclic and aromatic 
(d) heterocyclic and aromatic. (1990) 
12.2 
12.4 
 
Nomenclature of Organic Compounds 
15. The correct IUPAC name for the compound 
11. The IUPAC name of the compound 
(a) 5-formylhex-2-en-3-one 
(b) 5-methyl-4-oxohex-2-en-5-al 
(c) 3-keto-2-methylhex-5-enal 
(d) 3-keto-2-methylhex-4-enal (NEET 2017)
12. The structure of isobutyl group in an organic 
compound is 
(a) CH 3 —CH 2 —CH 2 —CH 2 — 
(b) 
(c) 
is 
(a) 4-ethyl-3-propylhex-1-ene 
(b) 3-ethyl-4-ethenylheptane 
(c) 3-ethyl-4-propylhex-5-ene 
(d) 3-(1-ethylpropyl)hex-1-ene. (2011) 
16. The IUPAC name of the following compound is 
(a) trans-2-chloro-3-iodo-2-pentene 
(b) c is-3-iodo-4-chloro-3-pentane 
(c) trans-3-iodo-4-chloro-3-pentene 
(d) c is-2-chloro-3-iodo-2-pentene. 
(Mains 2011, 1998) 
17. The IUPAC name of the compound 
(d) (NEET 2013) 
13. Structure of the compound whose IUPAC name is 
3-ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid 
is 
(a) (b) 
CH 3CH CHC CH is 
(a)  pent-4-yn-2-ene (b)  pent-3-en-1-yne 
(c)  pent-2-en-4-yne (d)  pent-1-yn-3-ene. 
(Mains 2010) 
18. The IUPAC name of the compound having the 
formula CH C—CH CH 2 is 
(a) 1-butyne-3-ene (b) but-1-yne-3-ene 
(c)  1-butene-3-yne (d) 3-butene-1-yne. 
(c) (d) 
 
(NEET 2013) 
19. The IUPAC name of is 
(a) 1-chloro-1-oxo-2,3-dimethylpentane 
(b) 2-ethyl-3-methylbutanoyl chloride 
(2009) 
14. Which nomenclature is not according to IUPAC 
system? 
(a) Br – CH 2 – CH CH 2 
1-Bromoprop-2-ene 
CH 3 
(b) CH 3 – CH 2 – C – CH 2 – CHCH 3 
(c) 2,3-dimethylpentanoyl chloride 
(d) 3,4-dimethylpentanoyl chloride. (2006) 
20. Names of some compounds are given. Which one is 
not in IUPAC system? 
(a) 
Br CH 3 
(c) 
4-Bromo-2,4-dimethylhexane 
CH3 – CH – CH – CH 2 CH 3 
CH3 
2-Methyl-3-phenylpentane 
(b) 
(c) 
(d) CH3 – C – CH2 – CH2 – CH 2 COOH 
O 
5-Oxohexanoic acid 
(d) (2005) 
12.5 
(2012) 
Organic Chemistry - Some Basic Principles and Techniques 
21. Name of the compound given below is 
 
27. The IUPAC name of 
is 
(a) 4-ethyl-3-methyloctane 
(b) 3-methyl-4-ethyloctane 
(c) 2,3-diethylheptane 
(d) 5-ethyl-6-methyloctane. (2003) 
22. IUPAC name of the following is 
CH 2 CH – CH 2 – CH 2 – C CH 
(a) 1,5-hexenyne (b) 1-hexene-5-yne 
(c) 1-hexyne-5-ene (d) 1,5-hexynene. 
(2002) 
23. The incorrect IUPAC name is 
(a) - 2-methyl-3-butanone 
(b) -2,3-dimethylpentane 
(c) CH 3 – C CCH(CH 3) 2 -4-methyl-2-pentyne 
(d) -3-bromo-2-chlorobutane. 
(2001) 
24. The IU PA C nam e of (CH3 )2CH – CH2 – CH2Br is 
(a) 1-bromo-3-methylbutane 
(b) 2-methyl-3-bromopropane 
(c) 1-bromopentane 
(d) 2-methyl-4-bromobutane. (1996) 
25. The IUPAC name for 
CH 3CH CHCH 2CHCH 2 COOH is 
| 
NH 2 
(a) 3-amino-5-heptenoic acid 
(b) ?-amino-?-heptenoic acid 
(c) 5-amino-2-heptenoic acid 
(d) 5-amino-hex-2-enecarboxylic acid. (1995) 
26. 2-Methyl-2-butene will be represented as 
(a) 
(b) 
(c) 
(d) (1992) 
(a) 4-hydroxy-1-methylpentanal 
(b) 4-hydroxy-2-methylpent-2-en-1-al 
(c) 2-hydroxy-4-methylpent-3-en-5-al 
(d) 2-hydroxy-3-methylpent-2-en-5-al. (1992) 
Isomerism 
28. Which among the given molecules can exhibit 
tautomerism? 
(a) III only (b) Both I and III 
(c) Both I and II (d) Both II and III 
(NEET-II 2016) 
29. Given : 
Which of the given compounds can exhibit 
tautomerism? 
(a) II and III (b) I, II and III 
(c)  I and II (d) I and III 
(2015, Cancelled) 
30. The enolic form of ethyl acetoacetate as shown 
below has 
(a) 9 sigma bonds and 2 pi-bonds 
(b) 9 sigma bonds and 1 pi-bond 
(c) 18 sigma bonds and 2 pi-bonds 
(d) 16 sigma bonds and 1 pi-bond. (2015, Cancelled) 
31. Which one of the following pairs represents 
stereoisomerism? 
(a) Structural isomerism and geometrical isomerism 
(b) Optical isomerism and geometrical isomerism 
(c) Chain isomerism and rotational isomerism 
(d) Linkage isomerism and geometrical isomerism 
(2005) 
32. The molecular formula of diphenylmethane, 
is C 13H 12. 
How many structural isomers are possible when one 
of the hydrogen is replaced by a chlorine atom? 
(a) 6 (b) 4 (c) 8 (d) 7 (2004) 
12.6 
Page 4


 
 
Tetravalence of Carbon : Shapes of 
Organic Compounds 
1. The number of sigma ( ?) and pi ( ?) bonds in pent- 
2-en-4-yne is 
(a) 13 ? bonds and no ? bond 
(b) 10 ? bonds and 3 ? bonds 
(c) 8 ? bonds and 5 ? bonds 
(d) 11 ? bonds and 2 ? bonds. (NEET 2019) 
2. Which of the following molecules represents the 
order of hybridisation sp
2
, sp
2
, sp, sp from left to 
right atoms? 
(a) HC C — C CH 
(b) CH 2 CH — C CH 
(c) CH 2 CH — CH CH 2 
(d) CH 3 — CH     CH — CH 3 (NEET 2018) 
3. The total number of p-bond electrons in 
the following structure is 
(a) 12 (b) 16 (c)  4 (d) 8 
(2015, Cancelled) 
4. The state of hybridisation of C 2, C 3, C 5 and C 6 of the 
hydrocarbon, 
(a) sp, sp
2
, sp
3 
(b) sp
3
, sp
2
, sp 
(c)  sp
2
, sp, sp
3 
(d) sp, sp
3
, sp
2 
(2008) 
6. In which of the following compounds there is more 
than one kind of hybridisation (sp, sp
2
, sp
3
) for 
carbon?         
(a) CH2 CH – CH   CH 2 
(b) H – C C – H 
(c) CH 3CH 2CH 2CH 3 
(d) CH 3 – CH     CH – CH 3 
(1995) 
7. A straight chain hydrocarbon has the molecular 
formula C 8H 10. The hybridisation of the carbon 
atoms from one end of the chain to the other are 
respectively sp
3
, sp
2
, sp
2
, sp
3
, sp
2
, sp
2
, sp and sp. The 
structural formula of the hydrocarbon would be 
(a) CH 3C      CCH 2 – CH     CHCH   CH 2 
(b) CH 3CH 2 – CH    CHCH    CHC    CH 
(c) CH 3CH     CHCH 2 – C      CCH   CH 2 
(d) CH 3CH CHCH 2 – CH CHC CH (1991) 
8. Which of the following possesses a sp-carbon in 
its structure? 
(a) CH 2 CCl – CH CH 2 
(b) CCl 2 CCl 2 (c)  CH 2 C CH 2 
(d) CH 2 CH – CH CH 2 
(1989) 
9. The Cl–C–Cl angle in 1, 1, 2, 2-tetrachloro-
ethene and tetrachloromethane respectively will be 
about 
CH
3
 CH
3
 
(a)  120° and 109.5° (b) 90° and 109.5° 
(c)  109.5° and 90° (d) 109.5° and 120° 
CH
3 
– C – CH CH – CH – C CH (1988) 
7 6 
5 4 3 2 1 
CH
3
 
is in the following sequence 
(a) sp
3
, sp
2
, sp
2 
and sp (b) sp, sp
2
, sp
2 
and sp
3
 
Classification of Organic Compounds 
10. An  organic   compound   X(molecular   formula   
C H O N) has six carbon atoms in a ring system, 
(c) sp, sp
2
, sp
3 
and sp
2 
(d) sp, sp
3
, sp
2 
and sp
3
 6 7 2 
5. In the hydrocarbon, 
CH
3 
– CH CH– CH
2
– C CH 
(2009) 
two double bonds and a nitro group as substituent, 
X is 
(a) homocyclic but not aromatic 
6 5 4 3 2 1 (b) aromatic but not homocyclic 
the state of hybridisation of carbons 1, 3 and 5 are in 
the following sequence 
(c) homocyclic and aromatic 
(d) heterocyclic and aromatic. (1990) 
12.2 
12.4 
 
Nomenclature of Organic Compounds 
15. The correct IUPAC name for the compound 
11. The IUPAC name of the compound 
(a) 5-formylhex-2-en-3-one 
(b) 5-methyl-4-oxohex-2-en-5-al 
(c) 3-keto-2-methylhex-5-enal 
(d) 3-keto-2-methylhex-4-enal (NEET 2017)
12. The structure of isobutyl group in an organic 
compound is 
(a) CH 3 —CH 2 —CH 2 —CH 2 — 
(b) 
(c) 
is 
(a) 4-ethyl-3-propylhex-1-ene 
(b) 3-ethyl-4-ethenylheptane 
(c) 3-ethyl-4-propylhex-5-ene 
(d) 3-(1-ethylpropyl)hex-1-ene. (2011) 
16. The IUPAC name of the following compound is 
(a) trans-2-chloro-3-iodo-2-pentene 
(b) c is-3-iodo-4-chloro-3-pentane 
(c) trans-3-iodo-4-chloro-3-pentene 
(d) c is-2-chloro-3-iodo-2-pentene. 
(Mains 2011, 1998) 
17. The IUPAC name of the compound 
(d) (NEET 2013) 
13. Structure of the compound whose IUPAC name is 
3-ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid 
is 
(a) (b) 
CH 3CH CHC CH is 
(a)  pent-4-yn-2-ene (b)  pent-3-en-1-yne 
(c)  pent-2-en-4-yne (d)  pent-1-yn-3-ene. 
(Mains 2010) 
18. The IUPAC name of the compound having the 
formula CH C—CH CH 2 is 
(a) 1-butyne-3-ene (b) but-1-yne-3-ene 
(c)  1-butene-3-yne (d) 3-butene-1-yne. 
(c) (d) 
 
(NEET 2013) 
19. The IUPAC name of is 
(a) 1-chloro-1-oxo-2,3-dimethylpentane 
(b) 2-ethyl-3-methylbutanoyl chloride 
(2009) 
14. Which nomenclature is not according to IUPAC 
system? 
(a) Br – CH 2 – CH CH 2 
1-Bromoprop-2-ene 
CH 3 
(b) CH 3 – CH 2 – C – CH 2 – CHCH 3 
(c) 2,3-dimethylpentanoyl chloride 
(d) 3,4-dimethylpentanoyl chloride. (2006) 
20. Names of some compounds are given. Which one is 
not in IUPAC system? 
(a) 
Br CH 3 
(c) 
4-Bromo-2,4-dimethylhexane 
CH3 – CH – CH – CH 2 CH 3 
CH3 
2-Methyl-3-phenylpentane 
(b) 
(c) 
(d) CH3 – C – CH2 – CH2 – CH 2 COOH 
O 
5-Oxohexanoic acid 
(d) (2005) 
12.5 
(2012) 
Organic Chemistry - Some Basic Principles and Techniques 
21. Name of the compound given below is 
 
27. The IUPAC name of 
is 
(a) 4-ethyl-3-methyloctane 
(b) 3-methyl-4-ethyloctane 
(c) 2,3-diethylheptane 
(d) 5-ethyl-6-methyloctane. (2003) 
22. IUPAC name of the following is 
CH 2 CH – CH 2 – CH 2 – C CH 
(a) 1,5-hexenyne (b) 1-hexene-5-yne 
(c) 1-hexyne-5-ene (d) 1,5-hexynene. 
(2002) 
23. The incorrect IUPAC name is 
(a) - 2-methyl-3-butanone 
(b) -2,3-dimethylpentane 
(c) CH 3 – C CCH(CH 3) 2 -4-methyl-2-pentyne 
(d) -3-bromo-2-chlorobutane. 
(2001) 
24. The IU PA C nam e of (CH3 )2CH – CH2 – CH2Br is 
(a) 1-bromo-3-methylbutane 
(b) 2-methyl-3-bromopropane 
(c) 1-bromopentane 
(d) 2-methyl-4-bromobutane. (1996) 
25. The IUPAC name for 
CH 3CH CHCH 2CHCH 2 COOH is 
| 
NH 2 
(a) 3-amino-5-heptenoic acid 
(b) ?-amino-?-heptenoic acid 
(c) 5-amino-2-heptenoic acid 
(d) 5-amino-hex-2-enecarboxylic acid. (1995) 
26. 2-Methyl-2-butene will be represented as 
(a) 
(b) 
(c) 
(d) (1992) 
(a) 4-hydroxy-1-methylpentanal 
(b) 4-hydroxy-2-methylpent-2-en-1-al 
(c) 2-hydroxy-4-methylpent-3-en-5-al 
(d) 2-hydroxy-3-methylpent-2-en-5-al. (1992) 
Isomerism 
28. Which among the given molecules can exhibit 
tautomerism? 
(a) III only (b) Both I and III 
(c) Both I and II (d) Both II and III 
(NEET-II 2016) 
29. Given : 
Which of the given compounds can exhibit 
tautomerism? 
(a) II and III (b) I, II and III 
(c)  I and II (d) I and III 
(2015, Cancelled) 
30. The enolic form of ethyl acetoacetate as shown 
below has 
(a) 9 sigma bonds and 2 pi-bonds 
(b) 9 sigma bonds and 1 pi-bond 
(c) 18 sigma bonds and 2 pi-bonds 
(d) 16 sigma bonds and 1 pi-bond. (2015, Cancelled) 
31. Which one of the following pairs represents 
stereoisomerism? 
(a) Structural isomerism and geometrical isomerism 
(b) Optical isomerism and geometrical isomerism 
(c) Chain isomerism and rotational isomerism 
(d) Linkage isomerism and geometrical isomerism 
(2005) 
32. The molecular formula of diphenylmethane, 
is C 13H 12. 
How many structural isomers are possible when one 
of the hydrogen is replaced by a chlorine atom? 
(a) 6 (b) 4 (c) 8 (d) 7 (2004) 
12.6 
3 2 2 
3 2 2 3 
 
33. Tautomerism is exhibited by 
(a) R 3 CNO2 (b) RCH 2NO 2 
(c)  (CH 3) 3 CNO (d) (CH 3) 2NH (1997) 
34. The number of isomers in C 4H 10O will be 
(a) 7 (b) 8 (c) 5 (d) 6 (1996) 
35. Isomers of a substance must have the same 
(a) structural formula (b) physical properties 
(c) chemical properties (d) molecular formula. 
(1991) 
36. How many chain isomers could be obtained from 
the alkane C 6H14 ? 
(a) Four (b) Five 
(c) Six (d) Seven (1988) 
Fundamental Concepts in Organic 
Reaction Mechanism 
37. A tertiary butyl carbocation is more stable than a 
secondary butyl carbocation because of which of the 
following? 
(a) –I effect of – CH 3 groups 
(b) +R effect of – CH 3 groups 
(c) –R effect of – CH 3 groups 
(d) Hyperconjugation (NEET 2020) 
38. The most stable carbocation, among the following is 
(a) (CH ) C—C
+
 H—CH 
can form a bond by accepting a pair of electrons 
from a nucleophile 
(c) electrophile can be either neutral or positively 
charged species and can form a bond by 
accepting a pair of electrons from a nucleophile 
(d) electrophile is a negatively charged species and 
can form a bond by accepting a pair of electrons 
from a nucleophile. (NEET 2017)
42. Which of the following statements is not correct for 
a nucleophile? 
(a) Ammonia is a nucleophile. 
(b) Nucleophiles attack low e
– 
density sites. 
(c) Nucleophiles are not electron seeking. 
(d) Nucleophile is a Lewis acid. (2015) 
43. Treatment of cyclopentanone   with methyl 
lithium gives which of the following species? 
(a) Cyclopentanonyl radical 
(b) Cyclopentanonyl biradical 
(c) Cyclopentanonyl anion 
(d) Cyclopentanonyl cation (2015, Cancelled)
44. Which of the following is the most correct electron 
displacement for a nucleophilic reaction to take place? 
(a) 
3  3 3 
(b) CH —CH —C
+
H—CH —CH 
(c) CH —C
+
H—CH —CH —CH 
(b) 
(c) 
(d) CH —CH —C
+
 H (Odisha NEET 2019)
3 2 2 
39. Which of the following is correct with respect to – I 
effect of the substituents? (R = alkyl) 
(a)  – NH 2 < – OR < – F (b) – NR 2 < – OR < – F 
(c)  – NH 2 > – OR > – F (d) – NR 2 > – OR > – F 
(NEET 2018, 1998) 
40. Which of the following carbocations is expected to 
be most stable? 
(a) (b) 
(c) (d) 
(NEET 2018) 
41. The correct statement regarding electrophile is 
(a) electrophile is a negatively charged species and 
can form a bond by accepting a pair of electrons 
from another electrophile 
(b) electrophiles are generally neutral species and 
(d) (2015, Cancelled) 
45. Consider the following compounds : 
Hyperconjugation occurs in 
(a) III only (b) I and III 
(c) I only (d) II only. 
(2015, Cancelled) 
46. In which of the following compounds, the C—Cl 
bond ionisation shall give most stable carbonium 
ion? 
(a) (b) 
(c) (d)  
(2015, Cancelled) 
12.7 
3 
Page 5


 
 
Tetravalence of Carbon : Shapes of 
Organic Compounds 
1. The number of sigma ( ?) and pi ( ?) bonds in pent- 
2-en-4-yne is 
(a) 13 ? bonds and no ? bond 
(b) 10 ? bonds and 3 ? bonds 
(c) 8 ? bonds and 5 ? bonds 
(d) 11 ? bonds and 2 ? bonds. (NEET 2019) 
2. Which of the following molecules represents the 
order of hybridisation sp
2
, sp
2
, sp, sp from left to 
right atoms? 
(a) HC C — C CH 
(b) CH 2 CH — C CH 
(c) CH 2 CH — CH CH 2 
(d) CH 3 — CH     CH — CH 3 (NEET 2018) 
3. The total number of p-bond electrons in 
the following structure is 
(a) 12 (b) 16 (c)  4 (d) 8 
(2015, Cancelled) 
4. The state of hybridisation of C 2, C 3, C 5 and C 6 of the 
hydrocarbon, 
(a) sp, sp
2
, sp
3 
(b) sp
3
, sp
2
, sp 
(c)  sp
2
, sp, sp
3 
(d) sp, sp
3
, sp
2 
(2008) 
6. In which of the following compounds there is more 
than one kind of hybridisation (sp, sp
2
, sp
3
) for 
carbon?         
(a) CH2 CH – CH   CH 2 
(b) H – C C – H 
(c) CH 3CH 2CH 2CH 3 
(d) CH 3 – CH     CH – CH 3 
(1995) 
7. A straight chain hydrocarbon has the molecular 
formula C 8H 10. The hybridisation of the carbon 
atoms from one end of the chain to the other are 
respectively sp
3
, sp
2
, sp
2
, sp
3
, sp
2
, sp
2
, sp and sp. The 
structural formula of the hydrocarbon would be 
(a) CH 3C      CCH 2 – CH     CHCH   CH 2 
(b) CH 3CH 2 – CH    CHCH    CHC    CH 
(c) CH 3CH     CHCH 2 – C      CCH   CH 2 
(d) CH 3CH CHCH 2 – CH CHC CH (1991) 
8. Which of the following possesses a sp-carbon in 
its structure? 
(a) CH 2 CCl – CH CH 2 
(b) CCl 2 CCl 2 (c)  CH 2 C CH 2 
(d) CH 2 CH – CH CH 2 
(1989) 
9. The Cl–C–Cl angle in 1, 1, 2, 2-tetrachloro-
ethene and tetrachloromethane respectively will be 
about 
CH
3
 CH
3
 
(a)  120° and 109.5° (b) 90° and 109.5° 
(c)  109.5° and 90° (d) 109.5° and 120° 
CH
3 
– C – CH CH – CH – C CH (1988) 
7 6 
5 4 3 2 1 
CH
3
 
is in the following sequence 
(a) sp
3
, sp
2
, sp
2 
and sp (b) sp, sp
2
, sp
2 
and sp
3
 
Classification of Organic Compounds 
10. An  organic   compound   X(molecular   formula   
C H O N) has six carbon atoms in a ring system, 
(c) sp, sp
2
, sp
3 
and sp
2 
(d) sp, sp
3
, sp
2 
and sp
3
 6 7 2 
5. In the hydrocarbon, 
CH
3 
– CH CH– CH
2
– C CH 
(2009) 
two double bonds and a nitro group as substituent, 
X is 
(a) homocyclic but not aromatic 
6 5 4 3 2 1 (b) aromatic but not homocyclic 
the state of hybridisation of carbons 1, 3 and 5 are in 
the following sequence 
(c) homocyclic and aromatic 
(d) heterocyclic and aromatic. (1990) 
12.2 
12.4 
 
Nomenclature of Organic Compounds 
15. The correct IUPAC name for the compound 
11. The IUPAC name of the compound 
(a) 5-formylhex-2-en-3-one 
(b) 5-methyl-4-oxohex-2-en-5-al 
(c) 3-keto-2-methylhex-5-enal 
(d) 3-keto-2-methylhex-4-enal (NEET 2017)
12. The structure of isobutyl group in an organic 
compound is 
(a) CH 3 —CH 2 —CH 2 —CH 2 — 
(b) 
(c) 
is 
(a) 4-ethyl-3-propylhex-1-ene 
(b) 3-ethyl-4-ethenylheptane 
(c) 3-ethyl-4-propylhex-5-ene 
(d) 3-(1-ethylpropyl)hex-1-ene. (2011) 
16. The IUPAC name of the following compound is 
(a) trans-2-chloro-3-iodo-2-pentene 
(b) c is-3-iodo-4-chloro-3-pentane 
(c) trans-3-iodo-4-chloro-3-pentene 
(d) c is-2-chloro-3-iodo-2-pentene. 
(Mains 2011, 1998) 
17. The IUPAC name of the compound 
(d) (NEET 2013) 
13. Structure of the compound whose IUPAC name is 
3-ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid 
is 
(a) (b) 
CH 3CH CHC CH is 
(a)  pent-4-yn-2-ene (b)  pent-3-en-1-yne 
(c)  pent-2-en-4-yne (d)  pent-1-yn-3-ene. 
(Mains 2010) 
18. The IUPAC name of the compound having the 
formula CH C—CH CH 2 is 
(a) 1-butyne-3-ene (b) but-1-yne-3-ene 
(c)  1-butene-3-yne (d) 3-butene-1-yne. 
(c) (d) 
 
(NEET 2013) 
19. The IUPAC name of is 
(a) 1-chloro-1-oxo-2,3-dimethylpentane 
(b) 2-ethyl-3-methylbutanoyl chloride 
(2009) 
14. Which nomenclature is not according to IUPAC 
system? 
(a) Br – CH 2 – CH CH 2 
1-Bromoprop-2-ene 
CH 3 
(b) CH 3 – CH 2 – C – CH 2 – CHCH 3 
(c) 2,3-dimethylpentanoyl chloride 
(d) 3,4-dimethylpentanoyl chloride. (2006) 
20. Names of some compounds are given. Which one is 
not in IUPAC system? 
(a) 
Br CH 3 
(c) 
4-Bromo-2,4-dimethylhexane 
CH3 – CH – CH – CH 2 CH 3 
CH3 
2-Methyl-3-phenylpentane 
(b) 
(c) 
(d) CH3 – C – CH2 – CH2 – CH 2 COOH 
O 
5-Oxohexanoic acid 
(d) (2005) 
12.5 
(2012) 
Organic Chemistry - Some Basic Principles and Techniques 
21. Name of the compound given below is 
 
27. The IUPAC name of 
is 
(a) 4-ethyl-3-methyloctane 
(b) 3-methyl-4-ethyloctane 
(c) 2,3-diethylheptane 
(d) 5-ethyl-6-methyloctane. (2003) 
22. IUPAC name of the following is 
CH 2 CH – CH 2 – CH 2 – C CH 
(a) 1,5-hexenyne (b) 1-hexene-5-yne 
(c) 1-hexyne-5-ene (d) 1,5-hexynene. 
(2002) 
23. The incorrect IUPAC name is 
(a) - 2-methyl-3-butanone 
(b) -2,3-dimethylpentane 
(c) CH 3 – C CCH(CH 3) 2 -4-methyl-2-pentyne 
(d) -3-bromo-2-chlorobutane. 
(2001) 
24. The IU PA C nam e of (CH3 )2CH – CH2 – CH2Br is 
(a) 1-bromo-3-methylbutane 
(b) 2-methyl-3-bromopropane 
(c) 1-bromopentane 
(d) 2-methyl-4-bromobutane. (1996) 
25. The IUPAC name for 
CH 3CH CHCH 2CHCH 2 COOH is 
| 
NH 2 
(a) 3-amino-5-heptenoic acid 
(b) ?-amino-?-heptenoic acid 
(c) 5-amino-2-heptenoic acid 
(d) 5-amino-hex-2-enecarboxylic acid. (1995) 
26. 2-Methyl-2-butene will be represented as 
(a) 
(b) 
(c) 
(d) (1992) 
(a) 4-hydroxy-1-methylpentanal 
(b) 4-hydroxy-2-methylpent-2-en-1-al 
(c) 2-hydroxy-4-methylpent-3-en-5-al 
(d) 2-hydroxy-3-methylpent-2-en-5-al. (1992) 
Isomerism 
28. Which among the given molecules can exhibit 
tautomerism? 
(a) III only (b) Both I and III 
(c) Both I and II (d) Both II and III 
(NEET-II 2016) 
29. Given : 
Which of the given compounds can exhibit 
tautomerism? 
(a) II and III (b) I, II and III 
(c)  I and II (d) I and III 
(2015, Cancelled) 
30. The enolic form of ethyl acetoacetate as shown 
below has 
(a) 9 sigma bonds and 2 pi-bonds 
(b) 9 sigma bonds and 1 pi-bond 
(c) 18 sigma bonds and 2 pi-bonds 
(d) 16 sigma bonds and 1 pi-bond. (2015, Cancelled) 
31. Which one of the following pairs represents 
stereoisomerism? 
(a) Structural isomerism and geometrical isomerism 
(b) Optical isomerism and geometrical isomerism 
(c) Chain isomerism and rotational isomerism 
(d) Linkage isomerism and geometrical isomerism 
(2005) 
32. The molecular formula of diphenylmethane, 
is C 13H 12. 
How many structural isomers are possible when one 
of the hydrogen is replaced by a chlorine atom? 
(a) 6 (b) 4 (c) 8 (d) 7 (2004) 
12.6 
3 2 2 
3 2 2 3 
 
33. Tautomerism is exhibited by 
(a) R 3 CNO2 (b) RCH 2NO 2 
(c)  (CH 3) 3 CNO (d) (CH 3) 2NH (1997) 
34. The number of isomers in C 4H 10O will be 
(a) 7 (b) 8 (c) 5 (d) 6 (1996) 
35. Isomers of a substance must have the same 
(a) structural formula (b) physical properties 
(c) chemical properties (d) molecular formula. 
(1991) 
36. How many chain isomers could be obtained from 
the alkane C 6H14 ? 
(a) Four (b) Five 
(c) Six (d) Seven (1988) 
Fundamental Concepts in Organic 
Reaction Mechanism 
37. A tertiary butyl carbocation is more stable than a 
secondary butyl carbocation because of which of the 
following? 
(a) –I effect of – CH 3 groups 
(b) +R effect of – CH 3 groups 
(c) –R effect of – CH 3 groups 
(d) Hyperconjugation (NEET 2020) 
38. The most stable carbocation, among the following is 
(a) (CH ) C—C
+
 H—CH 
can form a bond by accepting a pair of electrons 
from a nucleophile 
(c) electrophile can be either neutral or positively 
charged species and can form a bond by 
accepting a pair of electrons from a nucleophile 
(d) electrophile is a negatively charged species and 
can form a bond by accepting a pair of electrons 
from a nucleophile. (NEET 2017)
42. Which of the following statements is not correct for 
a nucleophile? 
(a) Ammonia is a nucleophile. 
(b) Nucleophiles attack low e
– 
density sites. 
(c) Nucleophiles are not electron seeking. 
(d) Nucleophile is a Lewis acid. (2015) 
43. Treatment of cyclopentanone   with methyl 
lithium gives which of the following species? 
(a) Cyclopentanonyl radical 
(b) Cyclopentanonyl biradical 
(c) Cyclopentanonyl anion 
(d) Cyclopentanonyl cation (2015, Cancelled)
44. Which of the following is the most correct electron 
displacement for a nucleophilic reaction to take place? 
(a) 
3  3 3 
(b) CH —CH —C
+
H—CH —CH 
(c) CH —C
+
H—CH —CH —CH 
(b) 
(c) 
(d) CH —CH —C
+
 H (Odisha NEET 2019)
3 2 2 
39. Which of the following is correct with respect to – I 
effect of the substituents? (R = alkyl) 
(a)  – NH 2 < – OR < – F (b) – NR 2 < – OR < – F 
(c)  – NH 2 > – OR > – F (d) – NR 2 > – OR > – F 
(NEET 2018, 1998) 
40. Which of the following carbocations is expected to 
be most stable? 
(a) (b) 
(c) (d) 
(NEET 2018) 
41. The correct statement regarding electrophile is 
(a) electrophile is a negatively charged species and 
can form a bond by accepting a pair of electrons 
from another electrophile 
(b) electrophiles are generally neutral species and 
(d) (2015, Cancelled) 
45. Consider the following compounds : 
Hyperconjugation occurs in 
(a) III only (b) I and III 
(c) I only (d) II only. 
(2015, Cancelled) 
46. In which of the following compounds, the C—Cl 
bond ionisation shall give most stable carbonium 
ion? 
(a) (b) 
(c) (d)  
(2015, Cancelled) 
12.7 
3 
— 
3 
+ + 
C 
+ 
2 
Organic Chemistry - Some Basic Principles and Techniques  
47. The radical, is aromatic because it has 
52. Which one of the following is most reactive towards 
electrophilic reagent? 
(a) 7 p-orbitals and 7 unpaired electrons 
(b) 6 p-orbitals and 7 unpaired electrons 
(c) 6 p-orbitals and 6 unpaired electrons 
(d) 7 p-orbitals and 6 unpaired electrons. 
(NEET 2013) 
48. Arrange the following in increasing order of stability. 
+ 
1. (CH 3) 2 — C — CH 2 — CH 3 
(a) (b) 
(c) (d) 
(2011, 2010) 
2.   (CH 3) 3 
+
+ 
53. Which of the following species is not electrophilic in 
nature? 
+ 
3.    (CH 3) 2 — C H 4. CH 3 — C H 2 (a) Cl (b) BH 3 
+ 
5. C H 3 
(c) H O
+ 
(d)  N
+  
O (Mains 2010) 
(a) 5 < 4 < 3 < 1 < 2 (b) 4 < 5 < 3 < 1 < 2 
(c) 1 < 5 < 4 < 3 < 2 (d) 5 < 4 < 3 < 2 < 1 
(Karnataka NEET 2013) 
49. What is the hybridisation state of benzyl carbonium 
ion   ? 
54. The stability of carbanions in the following: 
(i) RC    C (ii) 
(iii) R 2C     CH (iv) R 3 C — CH2 
is in the order of 
(a) (iv) > (ii) > (iii) > (i) (b) (i) > (iii) > (ii) > (iv) 
(a) sp
2 
(b) spd
2 
(c) sp
2
d (d) sp
3
(Karnataka NEET 2013) 
50. Homolytic fission of the following alkanes forms 
free radicals CH 3 — CH 3, CH 3 — CH 2 — CH3 , 
(c)  (i) > (ii) > (iii) > (iv) (d)  (ii) > (iii) > (iv) >  (i) 
(2008) 
55. For (i) I
–
, (ii) Cl
–
, (iii) Br
–
, the increasing order of 
nucleophilicity would be 
(CH ) CH — CH , CH — CH — CH(CH ) . (a) Cl
–
 < Br
–
 < I
–
 (b) I
–
 < Cl
–
 < Br
–
 
3  2 3 3 2 
3
 
2
 (c) Br 
–
 < Cl
–
 < I
–
 (d)  I
–
 < Br
–
 < Cl
–
 (2007) 
Increasing order of stability of the radicals is 
• 
•
 56. Which amongst the following is the most stable 
(a) (CH3)2C —
•   
CH2 — CH 3
• 
< CH3 — CH — CH 3
< CH 3 — CH 2 < (CH 3) 3 C 
carbocation? 
• • 
(a) (b) 
(b) CH 3 — CH 2 < CH 3 — CH — CH 3 
• • 
< (CH 3) 2 C — CH 2 — CH 3 < (CH 3) 3 C 
(c) (d) – 
• • 
(c) CH 3 — CH 2 < CH 3 — CH — CH 3 
(2005) 
• • 
< (CH 3) 3C < (CH 3) 2 C— CH 2 — CH 3 57. Which of the following is the most stable carbocation 
• • 
(carbonium ion)? 
(d) (CH 3) 3C< (CH 3)2 C— CH 2 — CH 3 + + 
• • 
(a) CH3CH2 (b) (CH3)2CH 
< CH 3 — CH — CH 3 < CH 3 — CH 2 
(Karnataka NEET 2013) 
(c) (CH 3) 3 C (d) C 6 H 5 CH 2 (1991) 
51. Which one is a nucleophilic substitution reaction 
among the following? 
(a) 
(b) 
(c) 
(d) CH 3CHO + HCN ?? CH 3CH(OH)CN (2011) 
58. Cyclic hydrocarbon ‘A’ has all the carbon and hydrogen 
atomsinasingleplane.Allthecarbon –carbonbondshave 
the same length, less than 1.54 Å, but more than 1.34 Å. 
The bond angle will be 
(a) 109º28? (b) 100º 
(c) 180º (d) 120º (1989) 
Methods of Purification of Organic 
Compounds 
59. Paper chromatography is an example of 
(a) adsorption chromatography 
(b) partition chromatography 
(c) thin layer chromatography 
(d) column chromatography. (NEET 2020) 
12.8