NCERT Class 11 Chemistry Chapter 12 Organic Chemistry Basic Principles And Techniques Multiple Choice Questions

NCERT Solutions For Class 11 Chemistry Chapter 12 Organic Chemistry Basic Principles And Techniques Multiple Choice Questions

Question 1. The ease of dehydrohalogenation of an alkyl halide with alcoholic KOH is—

1. 3° <2° < 1°
2. 3° < 2° > 1°
3. 3° > 2° > 1°
4. 3° > 2° < 1°

Answer: 2. 3° < 2° > 1°

Question 2. Which will exhibit optical isomerism

Answer: 2

Question 3. Which of the following is sec-butyl Phenyl Vinyl (BPV)methane

Answer: 3

Question 4. The correct states of hybridisation of C₂ and C₃ in compound H₃C —CH=C=CH —CH₃

1. sp², sp³
2. sp², sp
3. sp², sp³
4. sp, sp

Answer: 2. sp², sp

Question 5. Under identical conditions, the S_N1 reaction will most efficiently with

1. Tert-butyl chloride
2. 2-methyl-l-chloropropane
3. 2-chloroquine
4. Vinyl Chloride

Answer: 1. Tert-butyl chloride

Question 6. Which one of the following characteristics belongs to an electrophile

1. It is any species having electron deficiency that reacts at an electron-rich C-centre
2. It is any species having electron enrichment, that reacts at an electron deficient-centre
3. It is cationic
4. It is anionic

Answer:  1. It is any species having electron deficiency that reacts at an electron-rich C-centre

Question 7. The most stable enol tautomer of MeCOCH₂CO₂Et 

1. CH₂=C(OH)CH₂CO₂Et
2. MeC(OH)—CHCO₂Et
3. MeCOCH=C(OH)OEt
4. CH₂=C(OH)CH=C(OH)OEt

Answer: 2. MeC(OH)—CHCO₂Et

Question 8. Order of stability of the carbocations

1. Ph₂C⁺CH₂Me

2. PhCH₂CH₂C⁺HPh

3. PhCH⁺CHMe

4. Ph₂C(Me)CH₂  is

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

Answer: 2. 1 > 2 > 3 > 4

Question 9. MeCH₂CH=CH₂ is stable than Me₂C=CH₂ because—

1. Inductive effect of group.
2. Resonance effect of Me-group.
3. Hyperconjugative effect of Me-group.
4. Resonance and inductive effects of Me-group.

Answer: 3. Hyperconjugative effect of Me-group.

Question 10. (+) and (-)-Lactic acid has the same molecular formula, C₃H₆O₃. They are related as

1. Structure isomers
2. Geometric isomers
3. Optical isomers
4. Homomers

Answer: 3. Optical isomers

Question 11. Which of the following statements is correct for 2-butene—

1. The C₁ —C₂ bond is an sp³ —sp³ σ -bond
2. The C₂— C₃ bond is an sp³—sp² σ -bond
3. The C₁—C₂ bond is an sp³—sp³ σ-bond
4. The C₁— C₂ bond is an sp²—sp² σ -bond

Answer: 3. The C₁—C₂ bond is an sp³—sp³ σ-bond

Question 12. Basicity of aniline is less than methyl amine, because—

1. Hyperconjugation effect of Me-group in MeNH₂
2. Resonance effect of the phenyl group in aniline
3. The molar mass of methylamine is less than that of aniline
4. Resonance effect of Me-group in MeNH₂

Answer: 2. Resonance effect of the phenyl group in aniline

Question 13. Tautomerism is exhibited by—

Answer: 1, 2 and 3

Question 14. Amongst the following, the one which can exist in a free state as a stable compound is—

1. C₇H₉O
2. C₈H₁₂O
3. C₆H₁₁O
4. C₁₀H₁₇O₂

Answer:  2. C₈H₁₂O

Question 15. The correct pair of compounds that gives blue coloration/ precipitate and white precipitate, respectively, when their Lassaigne’s test is separately done is—

1. NH₂NH₂ HCl and C1CH₂COOH

2. NH₂CSNH₂ and PhCH₂Cl

3. NH₂CH₂COOH and NH₂CONH₂

Answer: 4.

Question 16. The IUPAC name of the compound X is—

1. 4-cyano-4-methyl-2-isopentane
2. 2-cyano-2-methyl-4-isopentane
3. 2,2,-dimethyl-4-oxo pentane nitrile
4. 4-cyano-4-methyl-2-pentanone

Answer: 3. 2,2,-dimethyl-4-oxo pentane nitrile

Question 17. The optically active molecule is

Answer: 3

Question 18. (+) -2-chloro-2-phenylethane in toluene racemizes slowly in the presence of the small amount of SbCl5, due to the formation of—

1. Carbanion
2. Free-radical
3. Carbene
4. Carbocation

Answer: 4. Carbocation

Question 19. The order of decreasing ease abstraction of hydrogen atoms in the following Hb molecule is—

1. H_a>H_b>H_c
2. H_a>H_c>H_b
3. H_b>H_a>H_c
4. H_c > H_b>H_a

Answer: 2. H_a>H_c>H_b

Question 20. The most likely protonation site in the given molecule is

1. C-1
2. C-2
3. C-3
4. C-6

Answer: 1. C-1

Question 21. The 4-th higher homolog of ethane is—

1. Butane
2. Pentane
3. Hexane
4. Heptane

Answer: 3. Hexane

Question 22. Among the following structures, the one which is not a resonating structure of others is—

Answer: 4.

Question 23. The correct order of decreasing length of the bond as indicated by the arrow in the following structures is—

Answer: 3

Question Question 24. IUPAC name ofthe molecule, is

1. 5,6-dimethylhept-2-ene
2. 2,3-dimethylhept-5-ene
3. 5,6-dimethylhept-3-ene
4. 5-isopropyl hex-2-ene

Answer:  1. 5,6-dimethylhept-2-ene

Question 25. The correct statement regarding the given compound is—

1. All three compounds are chiral
2. Only 1 and 2 are chiral
3. 1 and 3 are diastereomers
4. Only 1 and 3 are chiral

Answer: 4. Only 1 and 3 are chiral

Question 26. In Lassaigne’s test for the detection of nitrogen in an organic compound, the appearance of blue colored

1. Ferric ferricyanide
2. Ferrous ferricyanide
3. Ferric ferrocyanide
4. Ferrous ferrocyanide

Answer: 3. Ferric ferrocyanide

Question 27. The reaction of methyl trichloroacetate (Cl₃CCO₂Me) with sodium methoxide (NaOMe) generates

1. Carbocation
2. Carbene
3. Carbanion
4. Carbon radical

Answer: 2. Carbene

Question 28. In a mixture, two ommtlomors are found to be present in the amount of 0f*% mu) 15% respectively. The enantiomeric excess (e,o) Is—

1. 85%
2. 15%
3. 70%
4. 60%

Answer: 3. 70%

Question 29. In the following compound, the number it ‘sp’ hybridized carbon is CH₂=C=CH-CH-C≡CH –

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

Answer: 3. 4

Question 30. Which of the following statements Is/are correct

Answer: 2 and 4

Question 31. The correct order of adding strengths of benzoic acid (X), hydroxybenzoic acid (Y), and p-nitrobenzoic acid (Z) is—

1. Y> Z > X
2. Z > Y > X
3. Z > X > Y
4. Y > X > Z

Answer:  3. Z > X > Y

Question 32. In the IUPAC system, PhCH₂CH₂CO₂H is named as—

1. 3-phenylpropanoid acid
2. Benzoyl acetic acid
3. Carboxyethyl benzene
4. 2-phenylpropanoid acid

Answer: 1. 3-phenylpropanoid acid

Question 33. The major product(s) obtained in the reaction Is/are

Answer: 1 and 4

Question 34. The possible product (s) to be obtained from the reaction of cyclobutyl amine with HNOz is/are—

Answer:  1 and 3

Question 35.  Identify the compound that exhibits tautomerism—

1. 2-pentanone
2. 2-butene
3. Lactic acid
4. Phenol

Answer:  2. 2-butene

Question 36. How many chiral compounds are possible on monochlorination of 2-methylbutane—

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

Answer: 1. 2

Question 37. Identify the compound that exhibits tautomerism—

1. 2-pentanone
2. 2-butene
3. Lactic acid
4. Phenol

Answer: 1. 2-pentanone

Question 38. The order of stability of the following carbocations is—

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

Answer: 1. 3>1>2

Question 39. Arrange the compounds in order of decreasing acidity

Answer: 4.

Question 40. A solution of (-)-l-chloro-l-phenylethane in toluene racemizes slowly in the presence of a small amount of SbCl₅, due to the formation of—

1. Free radical
2. Carbanion
3. Carbene
4. Carbocation

Answer:  4. Carbocation

Question 41. In S_N2 reactions, the correct order of reactivity for the compounds: CH₃Cl, CH₃CH₂Cl, (CH₃)₂CHCl and (CH₃)₃CCl is _____

1. (CH₃)₂CHCl > CH₃CH₂Cl > CH₃Cl > (CH₃)₃CC;
2. CHgCl > (CH₃)₂CHCl > CH₃CH₂CI > (CH₃)₃CCI
3. CH₃Cl > CH₃CH₂Cl > (CH₃)₂CHCl > (CH₃)₃CCl
4. CH₃CH₂Cl > CH₃CI > (CH₃)₂CHCl > (CH₃)₃CCl

Answer: 3. CH₃Cl > CH₃CH₂Cl > (CH₃)₂CHCl > (CH₃)₃CCl

Question 42. For the estimation of nitrogen, 1.4 g of an organic compounejÿwas digested by the Kjeldahl method, and the evolved ammonia was absorbed in 60 mL of M/10

1. 5%
2. 6%
3. 10%
4. 3%

Answer: 3. 10%

Question 43. In the Carius method of estimation of halogens, 250 g of an organic compound gave 141 g AgBr. Percentage of Br in the compound(Ag = 108, Br = 80)

1. 48
2. 60
3. 24
4. 36

Answer: 3. 24

Question 44. Which of the following compounds will exhibit

1. 2-phenyl-l-butene
2. 1,1 – diphenyl 1 – propane
3. 1-phenyl-2-button
4. 3 – phenyl – 1 – butene

Answer: 3. 1-phenyl-2-button

Question 45. The increasing order of S_N1 reactivity of the following compounds is—

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

Answer:  4. 2<1<3

Question 46. The resonance stability is minimal for the compound—

Answer: 2.

Question 47. Which of the following compounds will be suitable for Kjeldahl’s method of nitrogen estimation—

Answer: 4

Question 48. The increasing order of basicity of the following compounds is—

Answer: 1

Question 49. Consider the reactions:

Answer: 3

Question 50. Which undergoes nucleophilic substitution most easily—

Answer: 1

Question 51. IUPAC name ofthe compound,

1. Trans-2-chloro-3-iodo-2-pentene
2. Cis-3-iodo-4-chloro-3-pentane
3. Trans-3-iodo-4-chloro-3-pentene
4. Cis-2-chloro-3-iodo-2-pentene

Answer: 1. Trans-2-chloro-3-iodo-2-pentene

Question 52. Considering the state of hybridization of C-atoms, which one among the following is linear

1. CH₃—C₂—CH₂—CH₃
2. CH₃—CH=CH—CH₃
3. CH₃-C = C-CH₃
4. CH₂=CHCH₂C= C

Answer: 3. CH₃-C = C-CH₃

Question 53. Which is a nucleophilic substitution reaction—

Answer: 4

Question 54. Which is most reactive towards an electrophilic reagent—

Answer: 3.

Question 55. The correct order of increasing bond length of C—H, C — O, C—C and C=C is _

1. C—H < C—O < C—C < C=C
2. C—H<C=C<C—O<C—C
3. C—C < C=C < C—O < C—H
4. C—O<C—H<C—C<C=C

Answer: 2. C—H<C=C<C—O<C—C

Question 56. RCHO + NH₂NH₂→RCH=N—NH₂ What sort of reactions it—

1. Electrophilic addition-elimination reaction
2. Free radical addition-elimination reaction
3. Electrophilic substitution-elimination reaction
4. Nucleophilic addition-elimination reaction

Answer: 4. Nucleophilic addition-elimination reaction

Question 57. Which of the following acids do not exhibit optical

1. Maleic acid
2. Amino acids
3. Lactic acid
4. Tartaric acid

Answer: 1. Maleic acid

Question 58. The correct order of decreasing acid strength of trichloroacetic acid (I), trifluoroacetic acid (n), acetic acid (in), and formic acid (IV) is—

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

Answer: 1. 2>1> 4>3

Question 59. Which nomenclature is not according to the IUPAC system

Answer: 3

Question 60. Structure of the company whose IlIPAC name is 3-ethyl- 2-hydroxy-4-methylhex-3-en-5-yonic acid is

Answer: 4

Question 61. The structure of the isobutyl group an organic compound is —

Answer: 2

Question 62. The order of stability of the following tautomeric forms is—

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

Answer: 3. 3>2>1

Question 63. Which of the following compounds will undergo racemization when a solution of KOH hydrolyses—

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

Answer: None of  these

Question 64. Most reactive towards nucleophilic addition reaction is—

Answer:  4

Question 65. In Kjeldahl’s method for estimation of nitrogen present in a soil sample, ammonia evolved from 0.75 g of sample neutralized 10 mL of 1M H₂SO₄ The percentage of nitrogen in the soils—

1. 37.33
2. 45.33
3. 35.33
4. 43.33

Answer: 1. 37.33

Question 66. The number of structural isomers possible from the molecular formula C₃H₉N is

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

Answer:  1. 4

Question 67.  In an S_N1 reaction on chiral centres there is__________

1. 100% racemisation
2. Inversion more than retention leading to partial racemization
3. 100% retention
4. 100%Inversion

Answer:  2. Inversion more than retention leading to partial racemization

Question 68. Which of the following statements is not correct for a nucleophile—

1. A nucleophile is a Lewis acid
2. Ammonia is a nucleophile
3. Nucleophiles attack electron density sites
4. Nucleophiles are not electron-seeking

Answer: 1, 2,3 and 4

Question 69. Two possible stereo-structures of CH3CHOH-COOH, which are optically active, are called—

1. Diastereomers
2. Atropisomers
3. Enantiomers
4. Mesotners

Answer: 3. Enantiomers

Question 70. In which of the following molecules, all the atoms are coplanar—

Answer: 4.

Question 71. The correct order of add strength of the given carboxylic acid is—

Answer: 3

Question 72. Which among the given molecules can exhibit tautomerism

Answer: 4

Question 73.  Which of the following biphenyls is optically active

Answer: 2

Question 74. The pair of electrons in the given carbanion is present in which ofthe following orbitals 

1. sp
2. 2p
3. sp
4. sp

Answer: 1. sp

Question 75. The correct statement about the basicity of aryl amines is—

1. Aryi amines are in general more basic than alkyl amines because the N-atom in aryl amines is sp hybridized
2. Aryi amines are in general less basic than alkyl amines because the unshared pair of electrons on nitrogen in aryi amines undergoes effective delocalization with the ring π-electrons
3. Aryi amines are in general more basic than alkyl amines because the unshared pair of electrons on nitrogen in aryi amines does not undergo delocalization with the ring electrons
4. Aryi amines are more basic than alkyl amines due to

Answer: 2. Aryi amines are in general less basic than alkyl amines because the unshared pair of electrons on nitrogen in aryi amines undergoes effective delocalization with the ring π-electrons

Question 76.  Which one of the following statements for the given
reactions are correct—

1. Is a substitution reaction but (2) and (3) are addition reactions.
2. (1) and (2) are elimination reactions, but (3) is an addition reaction.
3. (1) is an elimination reaction, (2) is a substitution reaction, and (3) is an addition reaction.
4. (1) is an elimination reaction, but (2) and (3) are substitution reactions.

Answer:  3. (1) is an elimination reaction, (2) is a substitution reaction, and (3) is an addition reaction.

Question 77. The IUPAC name ofthe compound 

1. 5-formylhex-2-en-3-one
2. 5-methyl-oxohex-2-en-5-al
3. 3-keto-2-methylhex-5-enal
4. 3-keto-2-methylhex-4-enal

Answer:  4. 3-keto-2-methylhex-4-enal

Question 78. Which one is the most acidic compound—

Answer: 3

Question 79. The most suitable method of separation of 1: a 1 mixture of ortho and para- nitrophenols is—

1. Chromatography
2. Crystallization
3. Steam distillation
4. Sublimation

Answer:  3. Steam distillation

Question 80. The correct statement regarding electrophile is—

1. Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from another electrophile
2. Electrophiles are generally neutral species and can form a bond by accepting a pair of electrons from a nucleophile
3. Electrophiles can be either neutral or positively charged species and can form a bond by accepting a pair ofelectrons from a nucleophile
4. Electrophile is a negatively charged species and can form a bond accepting a pair of electrons from a nucleophile

Answer: 3.  Electrophiles can be either neutral or positively charged species and can form a bond by accepting a pair ofelectrons from a nucleophile

Question 81. Which of the following is correct concerning -I effect of the substituents (R = alkyl) —

1. —NR₂ > —OR > —F
2. —NH₂ < —OR < —F
3. —NH₂ > —OR > —F
4. —NR₂ < —OR < —F

Answer: 2. —NH₂ < —OR < —F

Question 82. Which ofthe following carbocations is expected to be most stable—

Answer: 3.

Question 83. 3. Which of the following molecules represents the order of hybridization sp², sp², sp, sp from left to right atoms—

1. CH₃ —CH=CH —CH₃
2. HC=C —C=CH
3. CH₃=CH—CH=CH₂
4. CH₂=CH-C=CH

Answer: 4. CH₂=CH-C=CH

Question 84. S_N2 reaction readily occurs in—

Answer: 1.

Question 85. The correct decreasing order of pK_a is

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

Answer:  1. 2>4>1>3

Question 86.  The correct decreasing order of pK_b is—

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

Answer: 4. 4>2>1>3

Question 87. Find the dihydroxy cyclopentane—

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

Answer: 3. 3

Question 88. Decreasing order of nucleophilicity is—

1. OH^–>NH^–>CH₃O^–>RNH₂
2. NH^–>OH^–>CH₃O^–>RNH₂
3. NH^–>CH₃O^–>OH^–>RNH₂
4. CH₃O^–>NH^–>OH^–>RNH₂

Answer:  3. NH^–>CH₃O^–>OH^–>RNH₂

Question 89. pK_a increases in benzoic acid when substituent “x” is bonded at para-position, then “x” is—

1. —COOH
2. —NO₂
3. —CN
4. —OCH₃

Answer: 4. —OCH₃

Question 90. The IUPAC name of the given compound is (CH₃)₃CCH₂C(CH₃)₃

1. 2,3,4,4-tetramethylpentane
2. 1,2,2,4-tetramethylpentene
3. 2,2,4,4-tetramethylpentane
4. 3,3-dimethyl pentane

Answer: 3. 2,2,4,4-tetramethyl pentane

Question 91. The purity of an organic compound is determined by—

1. Chromatography
2. Crystallization
3. Melting or boiling point
4.  Both (1) and (3)

Answer: 4.  Both (1) and (3)

Question 92. Lassaigne’s test for the detection of nitrogen fails in—

1. H₂N—CO—NHNH₂.HCI
2. NH₂—NH₂HCI
3. C₆H₅—NH —NH₂. HCl
4.  C₆H₅CONH₂

Answer: 2. NH₂—NH₂HCI

Question 93. Among the following, the achiral amino acid is—

1. 2-ethylamine
2. 2-dimethylglycine
3. 2-hydroxymethyl serine
4. Tryptophan

Answer: 3. 2-hydroxymethyl serine

Question 94. Arrange the following nucleophiles in the decreasing order of nucleophilicity—

Answer:  4

Question 95. Which ofthe following is an electrophile—

1. CCl₂
2. CH₃^–
3. H₂O
4. NH₃

Answer: 1. CCl₂

Question 96. Give IUPAC the name ofthe following compound—

1. 5-hydroxy cyclo hex-3-en-1-one
2. 3-hydroxy cyclo hex-5-en-1-one
3. 8-hydroxy cyclo hex-3-en-1-one
4. 7-hydroxy cyclo hex-5-en-1-one

Answer:  1. 5-hydroxy cyclo hex-3-en-1-one

Question 97. Which of the following is the correct order of acidic strength of the following compounds

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

Answer:  2. 2 > 3> 1

Question 98. IUPAC name ofthe given compound is

1. 2-methoxy-4-bromonitrobenzene
2. 3-bromo-6-nitro-l-methoxybenzene
3. 3 -methoxy-4-nitrobromobenzene
4. 5-bromo-2-nitro-l-methoxybenzene

Answer: 4. 5-bromo-2-nitro-l-methoxybenzene

Question 99. The number of <r- and n -bonds in the pent-1-en-4-one molecule is respectively—

1. 8 and 2
2. 10 and 3
3. 6 and 4
4. 7 and 2

Answer: 2. 10 and 3

Question 100. The hybrid orbitals involved in the formation of the C₂— C₃ bond in the following compound, CH₂=CH — CH₂—CH₂—C≡CH are—

1. sp-sp²
2. sp-sp³
3. sp²-sp³
4. sp³-sp³

Answer: 3.  sp²-sp³

Question 101. The increasing order of electronegativity of the carbon atoms C-2, C-3 and C-4 in the compound CH₃ — C=C — CH₂ — CH=CH₂ is—

1. C-3 < C-2 < C-4
2. C-4 < C-3 < C-2
3. C-2 < C-4 < C-3
4. C-3 < C-4 < C-2

Answer: 1.  C-3 < C-2 < C-4

Question 102. CH₃CONH₂→CH₃CN; In this conversion, the change in the hybridization state of the carbon atom of the functional group is—

1. sp³-sp
2. sp³-sp
3. sp-sp³
4. sp³-sp³

Answer: 2. sp³-sp

Question 103. The correct shapes of CCl₄ and CCl₂=C=C=CCl₂ molecules are respectively—

1. Linear and tetrahedral
2. Planar and pyramidal
3. Tetrahedral and planar
4. Tetrahedral and linear

Answer: 3. Tetrahedral and planar

Question 104. The number of C and H-atoms that lie in the same plane in a toluene (C₆H₅CH₃) molecule is respectively—

1. 7 and 5
2. 6 and 5
3. 7 and 3
4. 6 and 3

Answer: 1.  7 and 5

Question 105. The number of primary, secondary, tertiary, and quaternary carbon atoms in 2,2,4-trimethylpentane is respectively—

1. 5,1,1 and 1
2. 1,1,1 and 5
3. 4,1,1 and 2
4. 1,5,1 and 1

Answer: 1. 5,1,1 and 1

Question 106. The number of primary, secondary, and tertiary H-atoms in the molecule is respectively—

1. 14,9 and 2
2. 15,9 and 1
3. 15,8 and 2
4. 15,8 and 1

Answer: 4.  15,8 and 1

Question 107. In which of the following molecules does all the atoms lie on the same straight line—

1. HC = C—C = CH
2. HC = C—CH₃
3. HC≡CN
4. C₃O₂

Answer: 2. HC = C—CH₃

Question 108. Hybridisation states of C-2, C-3, C-5 and C-6 in the com¬pound, (CH₃)₃CCH =CHCHC=CH are respectively—

1. sp, sp³, sp² and sp³
2. sp³, sp², sp² and sp
3. sp, sp², sp² and sp³
4. sp, sp², sp³ and sp²

Answer: 1. sp, sp³, sp² and sp³

Question 109. IUPAC name of the compound,

1. 1,1-diethyl-2,2-dimethyl pentane
2. 4,4-dimethyl-5,5-diethyl pentane
3. 5,5-diethyl-4,4-dimethyl heptane
4. 3-ethyl-4,4-dimethyl heptane

Answer: 4.  3-ethyl-4,4-dimethyl heptane

Question 110. IUPAC name of the compound,

1. 4-propyl-3-methylhex-5-en-2-one
2. 3-propyl-5-methylhex-l-en-5-one
3. 3-methyl-4-propyl hex-5-en-2-one
4. 3-methyl-4-vinylheptan-2-one

Answer:  3.  3-methyl-4-propyl hex-5-en-2-one

Question 111. Bond lengths of C—H, C—O, C—C and C follow the sequence—

1. C—H < C — O < C—C < C=C
2. C—H < C=C < C—O< C — C
3. C—C<C=C<C—O<C—H
4. C—O<C—H<C—C<C=C

Answer: 2. C—H < C=C < C—O < C — C

Question 112. IUPAC name of the compound

1. 1-chloro-2-nitro-4-methylbenzene
2. 1-chloro-4-methyl-2-nitrobenzene
3. 2-chloro-1-nitro-5-methylbenzene
4. m-nitro-p-chlorotoluene

Answer:  2. 1-chloro-4-methyl-2-nitrobenzene

Question 113. The correct IUPAC name of the alkyl group is—

1. 2-ethyl-3-sec-butyl propyl
2.  2,4-diethyl pentyl
3. 2-ethyl-4-methyl hexyl
4. 2-methyl-4-Ethylhexyl

Answer: 3.  2-ethyl-4-methyl hexyl

Question 114. The hybridization states of the carbon atom of the amido and cyano groups are respectively—

1. sp³ and sp²
2. sp² and sp
3. sp and sp²
4. sp³ and sp

Answer: 2.  sp² and sp

Question 115. Which of the following pair of compounds are isomers—

1. CH₃CH₂OH, CH₃OCH₃

2. CH₃OC₃H₇, C₂H₅OC₂H₅ .

3. CH₃CH₂CHO, CH₃COCH₃

4.

Answer: 4.

Question 116. Two aliphatic compounds will not be considered isomers if they are—

1. Aldehyde and ketone
2. Ether and alcohol
3. Ether and aldehyde
4. Carboxylic acid and ester

Answer: 3.  Ether and aldehyde

Question 117. The number of organic compounds with molecular formula C₄H₁₀ is—

1. 7
2. 5
3. 6
4. 8

Answer: 1. 7

Question 118. Only a monosubstituted compound is obtained when an alkane reacts with chlorine in the presence of UV light. The alkane is—

1. Propane
2. Pentane
3. Butane
4. Cyclohexane

Answer: 4.  Cyclohexane

Question 119. Two enantiomers rotate the plane of polarisation of plane polarised light

1. In different directions but keeping the angle the same
2. In the same direction but with different angles
3. In the same direction and the same angle
4. In different directions with different angles

Answer: 1.  In different directions but keeping the angle the same

Question 120. Which of the following is an optically active compound—

1. CH₃CHClCH=:CH₂
2. CH₃CHCl₂
3. Meso-tartaric acid
4. CH₃CH=C=CH₂

Answer: 1.  CH₃CHClCH=:CH₂

Question 121. Which of the following compounds exhibit both geometrical and optical isomerism—

1. CH₃CHClCH=C(CH₃)₂
2. CH₃CH=CH — CHBrCH₂CH₃
3. CH₂=C=CH—CH=CHCH₃
4. CH₃CH₂CH=CH₂

Answer: 2.  CH₃CH=CH — CHBrCH₂CH₃

Question 122. Which of the following compounds does not exhibit tautomerism—

1. CH₃CH₂N=O
2. CH₃NO₂
3. CH₃COCH₃
4. (CH₃)₃CCOC₆H₅

Answer: 4.  (CH₃)₃CCOC₆H₅

Question 123. The enol content in which of the following compounds is maximum—

1. CH₃COCH₂COCH₃

3. CH₃COCH₃

4. CH₃CHO

Answer: 1. CH₃COCH₂COCH₃

Question 124. The optically active alkane of the lowest molecular mass which is also chiral is—

1. 3-methyl hexane
2. 2, 3-dimethyl pentane
3. 2-methyl hexane
4. 2,5-dimethyl hexane

Answer: 1.  3-methylhexanec

Question 125. Which of the following compounds possesses a center of symmetry—

1. Trans-1,3-dimethylcyclobutane
2. Cis-1,3-dimethylcyclobutane
3. Trans-1-ethyl-3-methyl cyclobutane
4. Cis-l-ethyl-3-methyl cyclobutane

Answer: 1.  Trans-1,3-dimethylcyclobutane

Question 126. The compounds ds-2-butene and Frans-2-butene can be differentiated by

1. The number of products obtained due to their chlorination
2. The number of products obtained due to their bromination
3. Their reaction with H₂ in the presence of a nickel catalyst
4. Their respective boiling points

Answer:  4. Their respective boiling points

Question 127. Which of the following is optically active—

Answer: 4.

Question 128. Which of the following is non-superimposable on its mirror image—

Answer: 3

Question 129. The number of structural isomers that are formed when one H-atom of diphenylmethane   is substituted by chlorine is—

1. 4
2. 6
3. 8
4. 7

Answer: 1. 4

Question 103. The number of isomers formed by a compound whose molecular formula is C₂BrClFI is—

1. 3
2. 4
3. 5
4. 6 
   

Answer: 4. 6

Question 131.   In this reaction, the hydroxy acid obtained is—

1. (+)-enantiomer
2. (-)-enantiomer
3. 50% (+) and 50% (-)- enantiomer
4. 20% (+) and 80% (-)-enantiomer

Answer: 3.  50% (+) and 50% (-)- enantiomer

Question 132. Which of the following compounds will produce the most stable carbocation in the presence of an acid—

1. (CH₃)₂CHCH₂OH
2. CH₂=CH—CH₂OH
3. (CH₃)₂CHOH
4. (CH₃)₃COH

Answer: 2. CH₂=CH—CH₂OH

Question 133. The correct order of stability of the given carbanions:

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

Answer: 1. 1>2>3

Question 134. The most stable carbocation is—

Answer: 4.

Question 135. The most stable carbanion is—

Answer:  2

Question 136. Carbocation which does not undergo rearrangement is-

1. (CH₃)₂CH⁺CH₂
2. (CH₃)₂CH⁺CHCH₃
3.  (CH₃)₃⁺C
4. (CH₃)₃C⁺CH₂

Answer: 3.  (CH₃)₃⁺C

Question 137. Which of the following carbocations is quite stable and can even be stored in the laboratory as a salt— in which hyperconjugation does not occur—

1. (CH₃)₂ ⁺CH
2. (C₆H₅)₃⁺C
3.  CH₂=CH-⁺CH₂
4. ⁺CH₂CH₂C₆H₅

Answer: 2. (C₆H₅)₃⁺C

Question 138. Which of the given alicyclic compounds is most active—

1. C₆H₅C(CH₃)₃
2. C₆H₅CH₃
3. (CH₃)₂C=CH₂
4. CD₃CH=CH₂

Answer: 1. C₆H₅C(CH₃)₃

Question 139.  Which of the given resonance structures is most stable—

Answer: 4

Question 140. Which ofthe given alicyclic compounds is most active—

Answer: 2.

Question 141.

1. ^•CH₃
2. CH₃^•CH₂
3. CH₂=CH^•CH₂
4. C₆H₅^•CH₂

The correct order of stability of these free radicals is—

1. 1>2>3>4
2. 3>2>1>4
3. 4>3>2>1
4. 4>7>2>3

Answer: 3. 4>3>2>1

Question 142. The structures of carbocation and carbanion are respectively—

1. Linear and planar
2. Trigonal planar and trigonal pyramidal
3. Tetrahedral and trigonal planar
4. Trigonal pyramidal and tetrahedral

Answer: 2.  Trigonal planar and trigonal pyramidal

Question 143. The correct order of stability of the given three carbanions is—

Answer: 3

Question 144. Which of the following alkenes is most stable—

1. (CH₃)₂C=C(CH₃)₂
2. (CH₃)₂C=CHCH₂CH₃
3. CH₃CH₂CH=CHCH₂CH₃
4. CH₃CH₂CH₂CH₂CH=CH₂

Answer: 1.  (CH₃)₂C=C(CH₃)₂

Question 145. In which of the following compounds, the extent of resonance between the benzene ring and halogen atom is maximum—

Answer: 1

Question 146. The compound whose basicity is maximum in gaseous and aqueous medium is—

1. NH₃
2. CH₃NH₂
3. (CH₃)₂NH
4. (CH₃)₃N

Answer: 3. (CH₃)₂NH

Question 147. (+)-1-Chloro-1-phenylethane undergoes racemization in the presence of a small amount of SbCl₅.The intermediate formed in this process is—

1. A carbene
2. A carbocation
3. A carbanion
4. A free radical

Answer: 2.  A carbocation

Question 148. In which of the following compounds, the presence of nitrogen cannot be detected by Lassaigne’s test

1. NH₂NH₂.HCI
2. C₆H₅NHNH₂.HCI
3. PhN≡NPh
4. NH₂CONH₂

Answer: 1.  NH₂NH₂.HCI

Question 149. Which of the following compounds is responsible for the formation of Prussian blue during the detection of nitrogen by Lassaigne’s test

1. Na₄[Fe(CN)₆]
2. Fe₄[Fe(CN)₆]
3. Fe₂[Fe(CN)₆]
4. Fe₃[Fe(CN)6]₂

Answer: 2.  Fe₄[Fe(CN)₆]

Question 150. The process by which essential oils can be extracted from flowers is

1. Distillation
2. Crystallization
3. Vacuum distillation
4. Steam distillation

Answer: 4.  Steam distillation

Question 151. The process that is suitable for detecting two different types of ink in any handwritten ancient document is

1. Column chromatography
2. Solvent extraction
3. Distillation
4. Thin layer chromatography

Answer: 4.  Thin layer chromatography

Question1 52. Detection of which of the following functional groups is required to confirm the presence of nitrogen in the corresponding compound—

1. Amido
2. Carboxyl
3. Carbonyl
4. Alkoxycarbonyl

Answer: 1.  Amido

Question 153. Which of the following compounds does not exhibit geometrical isomerism—

Answer: 3.

Question 154. The number of geometrical isomers of the compound, CH₃CH=CH — CHCH₃ is_____

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

Answer: 1.  3

Question 155. Types of non-equivalent H-atoms in CH₃CH(OH)CH(OH)CH₃

1. 2
2. 4
3. 3
4. 6

Answer: 3. 3

Question 156. The number of compounds formed on monobromination

  is_________ 

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

Answer: 4.  4

Question 157.  Types of non-equivalent H-atoms in 

1. 2
2. 4
3. 3
4. 6

Answer: 2. 4

Question 158. The double bond equivalent of C₈H₉CIO is—

1. 4
2. 6
3. 3
4. 2

Answer: 1.  4

Question 159. The correct order of basicity of

1. CH₃NH₂
2. (CH₃)₂NH and
3. (CH₃)₃N

in chlorobenzene is—

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

Answer: 3. 1< 2< 3

Question 160. The correct order of stability of 

1. (CH₃)₂⁺CH

2. CH₃⁺CHOCH₃

3. ClCH₂⁺CHCH₃ is—

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

Answer: 3.  2 > 1> 3

Question 161. The correct order of stability of these carbanions is—

1. CH₃^–CH —CO —CH₃

2. CH₃CH₂-CO- ^–CH₂ and

3.  ^–CH₂CH₂— CO — CH₃ 

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

Answer: 1. 3<1<2

Question 162. In Kjeldahl’s method, CuSO₄ is used to—

1. Catalyze the reaction
2. Oxidise the reaction
3. Reduce the reaction
4. Increase boiling point

Answer: 1. Catalyse the reaction

Question 163. The number of optically active isomers among five probable alcohols of molecular formula C₄H₁₀O is—

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

Answer: 2. 2

Question 164. Which compound gives the most unstable enol—

Answer: 1.

Question 165. If 3.4% sulfur is present in insulin, then the minimum molecular mass of insulin will be—

1. 350
2. 470
3. 560
4. 940

Answer: 4. 940

Question 166. The number of enantiomer pairs formed on monochlorination of 2,3-dimethylbutane is—

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

Answer: 1. 1

Question 167. There are three different asymmetric carbon atoms in a compound. The number of possible stereoisomers of this compound is—

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

Answer: 1. 8

Question 168. In which of the following compounds, the nucleophilic character of N-atom is maximum—

Answer: 1

Question 169. Which of the following resonance structures is incorrect 

1. x>z>y
2. z>x>y
3. x>y>z
4. z>x>y

Answer: 3. x>y>z

Question 170. The number of electrons in the p-orbital of methyl cation is—

1. 2
2. 3
3. 4
4. None of these

Answer: 4. None of these

Question 171. Which compound can exhibit geometrical isomerism—

1. Acetone-oxime
2. Isobutene
3. Acetophenone-oxime
4. Benzophenone-oxime

Answer: 3. Acetophenone-oxime

Question 172. In the given compound, the hydrogen atom is linked to which carbon atom is most acidic—

1. C_α
2. C_β
3. C_γ
4. C_δ

Answer:   4. C_γ

Question 173. In which of the following molecules, all the constituent carbon atoms have the same state of hybridization—

1. HC≡C —C≡N
2. CH₃—C≡C —CH₂CH₃
3. CH₂=C=C=CH₂
4. CH₂=CH —CHO

Answer: 4.  CH₂=CH —CHO

Question 174. In which of the following molecules, all the atoms lie in the same plane—

1. CH₂=C=CH₂
2. CCI₂=C=C=CH₂
3. C₆H₅C=CH
4. CH₂=CH—C=CH

Answer: 2 and 3

Question 175. Which of the following express a homologous series—

1. Methanol, ethanol, 1-propanol
2. 1-hexene, 2-hexene, 3-hexene
3. Formic acid, acetic acid, propionic acid
4. Methane, methanol, methanal

Answer: 1 and 3

Question 176. Which of the following statements is incorrect—

1. Heat of hydrogenation of CH₃CH₂CH=CH₂ is less than that of (CH₃)₂C =CH
2. CCl₃ is more stable than CF₃
3. The bond lengths of three carbon-oxygen bonds in carbonate (CO^2-₃) ions are not equal.
4. Free radicals are paramagnetic

Answer: 1 and 3

Question 177.  Which of the following orders of stability are correct—

1. CH₃⁺CHOCH₃ > CH₃⁺CHCH2OCH₃
2. F⁺CH₂>FCH₂⁺CH₂
3. PhCH₂⁺CH₂>Ph⁺CH₂
4. FCH₂COO^–< CH₃COO^–

Answer:   a and 2

Question 178. Which process is not represented correctly—

Answer: 1 and 3

Question 179. Which ofthe following sets represent only electrophiles ______

1. BF₃, NH₃, H₂O
2. AICI₃, SO₃, ⁺NO₂
3. ⁺NO₂, ⁺CH₃, CH₃⁺CO
4. C₂H₅^–, ^•C₂H₅, C₂H⁺₅

Answer:  2 and 3

Question 180. Delocalisation in hyperconjugation occurs—

1. In the case of rr -bond electrons of the C — H bond of any alkyl group directly linked to a double bond (f)
2. In the case of cr -bond electrons of the C — H bond of any alkyl group directly linked to a positive carbon atom
3. In the case of a-electrons of C=C
4. In the case of a lone pair of electrons

Answer:  1 and 2

Question 181. Which of the following statements is incorrect—

1. Sodium extract is first boiled with dilute HC1 during the detection of halogens by Lassaigne’s test
2. If in an organic compound, both nitrogen and sulfur are present, then blood-red coloration is observed during the detection of nitrogen by Lassaigne’s test
3. Organic compounds that dissociate at their melting points are purified by vacuum distillation
4. In paper chromatography, the stationary phase is solid while the mobile phase is liquid

Answer: 1 and 4

Question 182. Which of the following compounds give a red coloration in Lassaigne’s test during the detection of nitrogen—

Answer:  3 and 4

Question 183. Which of the following mixtures is responsible for blue coloration in Lassaigne’s test during the detection of N—

1. NH₂NH₂ + charcoal
2. NH₄Cl + NaNO₃
3. C₆H₅COOH + NaNO₃
4. NH₂NH₂ + NH₄Cl

Answer: 1 and 3

Question 184. In which of the following structures, the arrangement of the four groups/atoms is different from that of  _________ 

Answer:   1 and 3

Question 185. Which ofthe following are optically active compounds ___________

Answer:  2 and 3

Question 186. In which of the following compounds, is the number of hypercoagulable hydrogen atoms is same—

Answer:  2 and 4

Question 187. For which of the following compounds, is the number of compounds formed on monobromination are same—

Answer:   1 and 2

Question 188. The carbocations which attain stability by resonance are___

Answer: 1,3, and 4

Question 189. Mixtures that can be separated by simple distillation are

1. A mixture of ether and toluene
2. A mixture of hexane and toluene
3. A mixture of benzene and chloroform
4. A mixture of 95% ethanol and 5% water

Answer:  1 and 3

Question 190. Compounds that can be purified by steam distillation are—

1. Acetic acid
2. o-nitrophenol
3. Ethanol
4. Nitrobenzene

Answer:  2 and 4

Question 191. Which of the following statements is incorrect—

1. Quantitative estimation of nitrogen in any compound can be done by Kjeldahl’s method
2. Quantitative estimation of sulfur in organic compounds can be done by the Dumas method
3. Quantitative estimation of halogens in organic compounds can be done by the Carius method
4. In Liebig’s method of detecting carbon and hydrogen in organic compounds, carbon is converted into carbon dioxide while hydrogen is converted into water

Answer: 1 and 3

Question 192. In which of the following processes, any organic liquid vapourises below its boiling point—

1. Vacuum distillation
2. Distillation
3. Steam distillation
4. Sublimation

Answer: 1 and 3

Question 193. Which exhibit optical and geometrical isomerism—

1. CH₃CHCICH=CH₂
2. CH₃-CHCI —CH=CH₂
3. CH₃CH=CH— CH(CH₃)₂
4. CH₃CH=CH—CH=C=CHCH₃

Answer: 2 and 4

Question 194. Which of the following are correct statements—

1. (CF₃)₃C⁺ is more stable than (CH₃)₃C⁺ ,
2. Na⁺does did not act as an electrophile
3. Ph₃C⁺ can be stored in the form of Ph₃C⁺BF^–₄ salt
4. CH₃CH₂O^– is less stable than O₂NCH₃CH₂O^–

Answer:  2 and 3

Question 195.  The nucleophilic reagents are—

1. OH^–
2. : NH₃
3. CCl₂
4. CN^–

Answer: 1,2 and 4

Question 196. The electrophilic reagents are—

1. ⁺NO₂
2. Cl⁺
3. H₂O
4. SO₃

Answer: 1, 2, 4

Question 197. Which of the following statements regarding Lassaigne’s test are correct—

1. N, S, and halogens are detected by converting them into their corresponding inorganic salts
2. This test is done to detect N, S, and hydrogen
3. Organic compounds are fused with sodium metal
4. Different halogens can be distinguished

Answer:  1,3 and 4

Question 198. Which of the following exhibits keto-enol tautomerism—

1. C₆H5COC₆H₅
2. C₆H₅COCH=CH₂
3. C₆H₅COCH₂COCH₃
4. CH₃COCH₂COCH₃

Answer:  2. C₆H₅COCH=CH₂

Question 199. Which of the following do not exhibit optical activity—

1. 3-methyl-l-pentene
2. 2-methyl-2-pentene
3. 4-methyl-l-pentene
4. 3-methyl-2-pentene

Answer: 2,3, and 4

Question 200. The correct statements are—

1. A racemic mixture is an equimolecular mixture of a pair of enantiomers
2. Configuration of a molecule means a stable three-dimensional arrangement of the groups attached to a specific atom of the molecule
3. The melting & boiling points of 2 enantiomers are different
4. A molecule may be optically active or inactive if more than one asymmetric carbon is present in the molecule

Answer: 1,2 and 4

Question 201. Which of the following are planar—

1. Ferf-butyl radical
2. Ferf-butyl carbocation
3. Ferf-butyl carbanion
4. Allyl carbanion

Answer: 1,2 and 4

Question 202. Which can act as both electrophile and nucleophile—

1. CH₃OH
2. CH₃Cl
3. CH₃CN
4. HCHO

Answer: 3 and 4

Question 203. Which of the following can act neither as an electrophile nor as a nucleophile

1. H₃O⁺
2. R₄N⁺
3. CN^–
4. SO₃

Answer: 1 and 2

Question 204. Which of the following conditions favor E2 reaction—

1. A strong base of high-concentration
2. A solvent of low polarity
3. 3° alkyl halide as the substrate
4. Alkyl iodide

Answer: 1,2,3,4

Question 205. Compounds that will not exhibit geometrical isomerism—

Answer:  1,2,3,

Question 206. In which ofthe following, a plane of symmetry is present—

Answer: 1,2,4

Question 207. Three stereoisomers of CH₂YZ are possible if the tire structure of methane is—

1. Rectangular planar
2. Square planar
3. square pyramidal
4. Octahedral

Answer: 1 and 2