Organic Chemistry 1000 Questions (Questions with Answers)

Multiple-Choice Questions in Organic Chemistry

Multiple choice questions usually include a phrase or stem followed by three to five options/choices.

Test strategies :

• Read the directions carefully

• Know if you are penalized for guessing

• Answer easy questions first

Answering options :

• Improve your odds, think critically

• Hide the options, read the stem, and try to answer

Select the option that most closely matches your answer

• Read the stem with each option

Treat each option as a true-false question, and choose the “most true”

Strategies to answer difficult questions :

• Eliminate options you know to be incorrect

• Question options that are totally unfamiliar to you

• Question options that contain negative or absolute words

• “All of the above”

If you know two of the three options seem correct, “all of the above” is a strong possibility

• Number answers :

Toss out the high and low and consider the middle range numbers

• “Look alike options”

Probably one is correct; choose the best but eliminate choices that mean basically the same thing, and thus cancel each other out

• Echo options :

If two options are opposite each other , chances are one of them is correct

• If two alternatives seem correct,

compare them for differences,

then refer to the stem to find your best answer

Guessing :

• Always guess when there is no penalty

for guessing or you can eliminate options

• Don’t guess if you are penalized

for guessing and if you have no basis for your choice

• Don’t change your answer

unless you are sure of the correction

When taking a test you are demonstrating your ability to understand your course material. Successful test taking avoids carelessness. Stay relaxed and confident. Remind yourself that you are well-prepared and going to do well. If you find yourself anxious, take several slow, deep breaths to relax. Don’t talk about the tests to other students just before it; anxiety is contagious.

This unit includes 1000 multiple choice questions. The purpose is to assess the breadth of student’s knowledge and understanding of the basic concepts of organic chemistry. Remember that the multiple choice questions :

1. are not simply definitions.

2. require application of recalled information, not simple recall.

3. require fine distinctions between correct and nearly-correct statements.

4. emphasize conceptual understanding

These questions have been especially designed to cover all the important concepts of organic chemistry. Solve them carefully. You will be glad that you did !

1. Which of the following is not a characteristic of organic compounds?

(a) They usually have low melting points.

(b) They usually are only slightly soluble or insoluble in water.

(d) Bonds which bind the atoms together are nearly always ionic.

Answer. (d)

2. The element least likely to be found in an organic compound is

(a) oxygen

(b) sulfur

(d) silicon

Answer. (d)

3. One of the major sources of organic compounds is

(a) Natural gas

(b) Fermentation

(d) Atmosphere

Answer. (a)

4. Catenation is a property of the carbon atom which describes its ability to

(a) bond with other carbon atoms

(b) form double and triple bonds

(d) form bonds in its ground state

Answer. (a)

5. In stable organic compounds, carbon will always form

(a) 2 bonds

(b) 4 bonds

(d) 5 bonds

Answer. (b)

6. Carbon-carbon double bonds consist of :

(a) one σ bond, one π bond

(b) two σ bonds, one π bond

(d) two σ bonds, two π bonds

Answer. (a)

7. Acetylene has a total of :

(a) one σ bond, two π bonds

(b) two σ bonds, four π bonds

(d) one σ bond, four π bonds

Answer. (c)

8. In propene there are

(a) eight σ bonds and one π bond

(b) seven σ bonds and two π bonds

(d) nine σ bonds

Answer. (a)

9. In propyne there are

(a) six σ bonds and two π bonds

(b) seven σ bonds and one π bond

(d) eight σ bonds

Answer. (a)

10. 1-Buten-3-yne has

(a) six σ and four π bonds

(b) seven σ and three π bonds

(d) nine σ and one π bond

Answer. (b)

11. Compound in which carbons use only sp3 hybrid orbitals for bond formation is

(a) CH₃CH₂CH₃

(b) CH₃C≡CH

(d) CH₂=CH—CH=CH₂

Answer. (a)

12. Compound in which carbon uses sp3 hybrid orbitals for bond formation is (a)

(b)

(c)

(d) (CH₃)₃COH

Answer. (d)

13. When the carbon atom is sp2 hybridized in a compound, it is bonded to

(a) 2 other atoms

(b) 4 other atoms

(d) 5 other atoms

Answer. (c)

14. Compound in which carbons use only sp2 hybrid orbitals for bond formation is

(a)

(b)

(d) CH₃CH=C=CH₂

Answer. (c)

15. Which of the following is a planar molecule?

(a) Formaldehyde

(b) Acetone

(d) Acetic acid

Answer. (a)

16. What is bond angle between the hybrid orbitals in methane?

(a) 180°

(b) 120°

(d) 115.5°

Answer. (c)

17. The H–C–C bond angle in ethane is

(a) 60°

(b) 109.5°

(d) 118°28′

Answer. (b)

18. The H–C–H bond angle in ethylene is

(a) 60°

(b) 120°

(d) 180°

Answer. (b)

19. What is the bond length of a carbon-carbon double bond?

(a) 1.20 Å

(b) 1.34 Å

(d) 1.68 Å

Answer. (b)

20. The carbon-carbon bond lengths in rank of increasing bond length is :

(a) triple, double, single

(b) single, double, triple

(d) triple, single, double

Answer. (a)

21. Which of the following is the correct order of bond lengths :

(a) C–C < C=C < C≡C

(b) C–C > C≡C > C=C

(d) C≡C < C–C > C=C

Answer. (a)

22. Which of the following hydrocarbons has the shortest C–C bond length?

(a) CH₂=CH₂

(b) CH₃CH₃

(d)

Answer. (c)

23. The carbon-carbon bond length is maximum in

(a) CH₂=CH₂

(b) CH₃CH₃

(d)

Answer. (b)

24. What is the hybridization of the carbon atoms numbered 1 and 2 respectively in the following structure?

(a) sp3, sp2

(b) sp2, sp2

(d) sp2, sp

Answer. (d)

25. How many atoms are attached to an atom having a sp hybridization?

(a) 0

(b) 1

(d) 3

Answer. (c)

26. Which statement is true?

(a) Resonance hybrids are inherently unstable.

(b) Resonance hybrids are more stable than any individual resonance form.

(d) Resonance hybrids are averages of all resonance forms resembling the more stable forms.

Answer. (d)

27. Resonance structures of a molecule have

(a) same arrangement of atoms

(b) different arrangement of atoms

(d) different number of paired electrons

Answer. (a) and (c)

28. Which of the following compounds have planar molecules?

(a) ethyl alcohol

(b) formaldehyde

(d) 1,3-butadiene

Answer. (b) and (d)

29. Which of the following compounds will show dipole moment?

(a) cis-1,2-dichloroethylene

(b) o-dichlorobenzene

(d) p-dichlorobenzene

Answer. (a) and (b)

30. Which molecule has a nonzero dipole moment?

(a) Cl₂

(b) CO₂

(d) CHCl₃

Answer. (d)

31. Which of the following compounds have lowest dipole moment?

(a) carbon tetrachloride

(b) chloromethane

(d) chloroform

Answer. (a)

32. Which molecule has the greatest dipole moment

(a) CH₃Cl

(b) CH₃Br

(d) CH₃I

Answer. (c)

33. Which of the following compounds have highest dipole moment?

(a) dichloromethane

(b) chloroform

(d) carbon tetrachloride

Answer. (a)

34. Homolytic fission of C–C bond leads to the formation of :

(a) Free radicals

(b) Carbonium ions

(d) None of these

Answer. (a)

35. Homolytic fission of covalent bond between carbon atoms will produce :

(a) Two carbonium ions

(b) Two molecules

(d) Carbonium ion and carbanion

Answer. (c)

36. The order of stability of carbonium ions is

(a) tertiary > secondary > primary

(b) secondary > tertiary > primary

(d) primary > tertiary > secondary

Answer. (a)

37. The order of stability of carbanions is

(a) primary > secondary > tertiary

(b) secondary > tertiary > primary

(d) tertiary > primary > secondary

Answer. (a)

38. Which of the following carbonium ions will be most stable? (a)

(b)

(c)

(d)

Answer. (d)

39. The least stable carbanion is :

(a)

(b)

(c)

(d)

Answer. (b)

40. Which alkyl free radical is the most stable?

(a) methyl

(b) primary

(d) tertiary

Answer. (d)

41. Which of the following is an electrophile? (a)

(b)

(c)

(d)

Answer. (b)

42. Which of the following is not an electrophile?

(a) NH₃

(b) Br+

(d) NO₂+

Answer. (a)

43. Which of the following statements is correct regarding nucleophiles?

(a) They have an overall positive charge

(b) They have a lone-pair of electrons

(d) They have empty orbitals

Answer. (b)

44. Which of the following is a nucleophile?

(a) AlCl₃

(b) H₃O+

(d) CN–

Answer. (d)

45. Which of the following is not a nucleophile?

(a) NH₃

(b) HSO₃–

(d) HO–

Answer. (c)

46. Which of the following is not a nucleophile? (a)

(b) BF₃

(c)

(d) NH₃

Answer. (b)

47. Which of the following is a Lewis acid?

(a) AlCl₃

(b) CH₃OH

(d) CH₃OCH₃

Answer. (a)

48. Which of the following ranges best represents the strength of a hydrogen bond?

(a) 5-10 kcals

(b) 60-80 kcals

(d) 100-120 kcals

Answer. (a)

49. Which describes the bond strength or bond dissociation energy?

(a) energy required to break a bond

(b) energy released when a bond breaks

(d) (a) and (c)

Answer. (d)

50. Which statement is correct?

(a) Energy is released when a bond breaks.

(b) A sigma bond results from attraction of protons and electrons.

(d) A carbanion is positively charged.

Answer. (c)

51. Which of the following is incorrect?

(a) Resonance stabilization is the extra stability a compound gains from having delocalized electrons.

(b) Delocalized electrons destabilize a compound.

(d) (a) and (c)

Answer. (b)

52. Which of the following is correct?

(a) Curved arrows are always drawn from an electron poor center to an electron rich center.

(b) A doubled headed arrow means one electron has been moved.

(d) A single headed arrow means two electrons have been moved.

Answer. (c)

53. What does a “curved” arrow represent?

(a) that two structures are resonance structures

(b) the movement of two electrons

(d) that two structures are equivalent

Answer. (b)

54. What is the predicted shape, bond angle, and hybridization for CH₃+?

(a) trigonal planar, 120°, sp2

(b) trigonal planar, 120°, sp3

(d) trigonal pyramidal, 120°, sp2

Answer. (a)

55. What is the name given for a species that contains a positively charged carbon atom?

(a) carbanion

(b) carbocation

(d) free radical

Answer. (c)

56. What orbitals overlap to create the H–C bond in CH₃+?

(a) sp3–sp3

(b) sp2–sp3

(d) s–sp2

Answer. (d)

57. The lone-pair electrons of the methyl anion occupy a orbital.

(a) s

(b) sp

(d) sp3

Answer. (d)

58. An increase in which of the following results in a decrease in the rate of the chemical reaction?

(a) temperature

(b) concentration

(d) energy of activation

Answer. (d)

59. The reaction step that has its transition state at the highest point on the reaction coordinate is the called the .

(a) rate-determining step

(b) activation energy

(d) product favored step

Answer. (a)

60. An electrophile acts as a when it reacts with a nucleophile.

(a) Bronsted-Lowry base

(b) Arrhenius base

(d) Lewis base

Answer. (c)

61. A nucleophile acts as a when it reacts with an electrophile.

(a) Bronsted-Lowry acid

(b) Arrhenius base

(d) Lewis base

Answer. (d)

62. Which of the following is not normally considered to be a nucleophile?

(a) NH₃

(b) CH₃NH₂

(d) CH₃CH₂+

Answer. (d)

63. Which of the following is not a nucleophile?

(a) FeBr₃

(b) Br–

(d) CH₃OCH₃

Answer. (a)

64. Which of the following is the strongest interaction?

(a) a covalent bond

(b) dipole-dipole interactions

(d) van der Waals

Answer. (a)

65. Which of the following statements is incorrect?

(a) Electrons move toward positively charged locations.

(b) An electron-rich atom is called an electrophile.

(d) A nucleophile has a a pair of electrons it can share.

Answer. (b)

66. Which of the following is a nonpolar molecule?

(a) HCl

(b) CH₃Cl

(d) NH₃

Answer. (c)

67. Which is defined as a species that accepts a proton?

(a) Lewis acid

(b) Lewis base

(d) Bronsted-Lowry base

Answer. (d)

68. Which statement is correct about acid-base chemistry?

(a) the larger the K_a, the stronger the acid

(b) a small pK_a correspond to a large K_a

(d) all of the above

Answer. (d)

69. Which of the following statements is correct?

(a) The stronger the acid, the weaker its conjugate base.

(b) The stronger the acid, the stronger its conjugate base.

(d) The stronger the acid, the weaker its conjugate acid.

Answer. (a)

70. What is the conjugate acid of CH₃NH₂?

(a) CH₃NH₃+

(b) CH₃NH–

(d) NH₂–

Answer. (a)

71. What is the conjugate base of CH3NH2?

(a) CH₃NH₃+

(b) CH₃NH–

(d) NH₂–

Answer. (b)

72. The stronger the acid .

(a) the less stable its conjugate base

(b) the larger the pK_a

(d) the larger the pH

Answer. (c)

73. Which of the following is the strongest acid?

(a) HI

(b) H₂O

(d) CH₃OH

Answer. (a)

74. Which of the following are Lewis bases?

(a) NF₃

(b) BF₃

(d) (a) and (c)

Answer. (d)

75. Two compounds have the same composition and also have the same atoms attached to the same atoms, although with different orientations in space. These compounds are

(a) Identical

(b) Position isomers

(d) Stereoisomers

Answer. (d)

76. The isomers of a substance must have

(a) same chemical properties

(b) same molecular weight

(d) same functional groups

Answer. (b)

77. Compounds with the same molecular formula but different structural formulas are called

(a) Alkoxides

(b) Iso compounds

(d) Ortho compounds

Answer. (c)

78. Ethanol (CH₃CH₂OH) and dimethyl ether (CH₃OCH₃) are best considered :

(a) structural isomers

(b) stereoisomers

(d) diastereomers

Answer. (a)

79. The compounds CH₃CH₂OCH₂CH₃ and CH₃OCH₂CH₂CH₃ are

(a) Enantiomers

(b) Conformational isomers

(d) Optical isomers

Answer. (c)

80. Which of the following statements is false about tautomers?

(a) Tautomers are structural isomers

(b) Tautomers are structural isomers which exist in dynamic equilibrium

(d) Tautomers have independent existence

Answer. (d)

81. How many isomers are possible for the compound with molecular formula C₄H₈?

(a) 2

(b) 4

(d) 8

Answer. (c)

82. How many structural isomers are possible for C₄H₉Br?

(a) 2

(b) 3

(d) 5

Answer. (c)

83. How many isomeric aromatic hydrocarbons are possible for C₈H₁₀?

(a) 3

(b) 4

(d) 6

Answer. (b)

84. Which compound is not an isomer of the other three?

(a) n-Pentane

(b) 2,2-Dimethylpropane

(d) 2,3-Dimethylbutane

Answer. (d)

85. Alkenes show geometrical isomerism due to :

(a) Asymmetry

(b) Rotation around a single bond

(d) Restricted rotation around a double bond

Answer. (d)

86. Which of the following compounds exhibit geometrical isomerism?

(a) 1-Pentene

(b) 2-Methyl-2-pentene

(d) 2-Methyl-2-butene

Answer. (c)

87. Which of the following compounds may exist as cis-trans isomers?

(a) 1-Butene

(b) 2-Butene

(d) Acetone

Answer. (b)

88. Geometrical isomerism is shown by

(a) Lactic acid

(b) Maleic acid

(d) 1,1-Dichloroethylene

Answer. (b)

89. Which of the following compounds show geometrical isomerism

(a) (CH₃)₃N

(b) CH₃CH=CH₂

(d) CH₃CH=CHCH₃

Answer. (d)

90. Which of the following compounds will show geometrical isomerism?

(a) CH₂=CHCl₂

(b) ClCH=CHBr

(d) Cl₂C=CBr₂

Answer. (b)

91. Which of the following compounds will not show geometrical isomerism?

(a) BrCH=CHBr

(b) BrCH=CHCl

(c)

(d)

Answer. (d)

92. A molecule is said to be chiral

(a) if it contains plane of symmetry

(b) if it contains centre of symmetry

(d) if it can be superimposed on its mirror image

Answer. (c)

93. Which of the statements is false regarding chiral compounds?

(a) rotate the plane of polarized light

(b) have cis and trans isomers

(d) can be detected with a polarimeter

Answer. (b)

94. An optically active compound

(a) must contain atleast four carbons

(b) when in solution rotate the plane of polarized light

(d) in solution always give a negative reading in polarimeter.

Answer. (b)

95. Plane-polarized light is affected by

(a) Identical molecules

(b) All polymers

(d) All biomolecules

Answer. (c)

96. It is possible to distinguish between optical isomers

(a) by using chemical tests

(b) by mass spectrometry

(d) by polarimetry

Answer. (d)

97. Optical isomers that are mirror images are called :

(a) Tautomers

(b) Diastereomers

(d) Metamers

Answer. (c)

98. Optical isomers that are not mirror images are called

(a) Diastereomers

(b) Enantiomers

(d) Meso compounds

Answer. (a)

99. Enantiomers have which of the following characteristics?

(a) rotate ordinary light

(b) have the same melting point

(d) react with optically active molecules at the same rate

Answer. (b)

100. Which of the following statements is false about enantiomers?

(a) rotate plane-polarized light

(b) are superimposable mirror images

(d) have the same melting point

Answer. (b)

101. A meso compound :

(a) is an achiral molecule which contains chiral carbons

(b) contains a plane of symmetry or a centre of symmetry

(d) is characterized by all of the above

Answer. (d)

102. What is the possible number of optical isomers for a compound containing n

dissimilar asymmetric carbon atoms?

(a) n2

(b) 2n

(d) n + 2

Answer. (b)

103. What is the possible number of optical isomers for a compound containing 2 dissimilar asymmetric carbon atoms?

(a) 2

(b) 4

(d) 8

Answer. (b)

104. meso-Tartaric acid is

(a) sometimes optically active

(b) always optically active

(d) always optically inactive

Answer. (d)

105. Which of the following compounds will be optically active?

(a) Propanoic acid

(b) 3-Chloropropanoic acid

(d) 3-Chloropropene

Answer. (c)

106. Which of the following compounds will be optically active?

(a) Succinic acid

(b) meso-Tartaric acid

(d) Lactic acid

(d) Chloroacetic acid

Answer. (c)

107. Which of the following isomeric compounds show optical isomerism :

(a) 1-Aminopentane

(b) 2-Aminopentane

(d) 2,2-Dimethylpropylamine

Answer. (b)

108. 2-Butanol is optically active because it contains :

(a) an asymmetric carbon

(b) a plane of symmetry

(d) a centre of symmetry

Answer. (a)

109. Optical isomerism is shown by

(a) n-Butyl chloride

(b) sec-Butyl chloride

(d) Isobutyl chloride

Answer. (b)

110. Which of the following compounds is an optically active compound? (a)

(b) CHCl₃

(d) CH₃CH₂OH

Answer. (a)

111. Lactic acid, , is a molecule which shows

(a) Geometrical isomerism

(b) Tautomerism

(d) Metamerism

Answer. (c)

112. How many optical isomers are possible for lactic acid?

(a) 2

(b) 4

(d) 8

Answer. (a)

113. Which of the following represents a racemic mixture?

(a) 75% (R)-2-butanol, 25% (S)-2-butanol

(b) 25% (R)-2-butanol, 75% (S)-2-butanol

(d) none of the above

Answer. (c)

114. Consider (R)- and (S)-2-butanol. Which physical property distinguishes the two compounds?

(a) melting point

(b) solubility in common solvents

(d) Infrared spectrum

Answer. (c)

115. Which of the following is capable of exhibiting cis-trans isomerism?

(a) 1-butene

(b) 1-pentene

(d) 2-butene

Answer. (d)

116. Which of the following is a true statement?

(a) All chiral molecules possess a plane of symmetry.

(b) All achiral molecules are meso.

(d) A mixture of achiral compounds will be optically inactive.

Answer. (d)

117. Which of the statements below correctly describes an achiral molecule?

(a) The molecule has a nonsuperimposable mirror image.

(b) The molecule exhibits optical activity when it interacts with plane-polarized light.

(d) The molecule might be a meso form.

Answer. (d)

118. How many asymmetric centers are present in a molecule of 2,4,6- trimethylheptane?

(a) 0

(b) 1

(d) 3

Answer. (a)

119. Which of the following compounds is never chiral?

(a) 2,3-dibromobutane

(b) 1,3-dibromobutane

(d) 1,4-dibromobutane

Answer. (d)

120. Which of the following statements is correct concerning a pair of enantiomers?

(a) They rotate the plane of polarized light by exactly the same amount and in opposite directions.

(b) They rotate the plane of polarized light by differing amounts and in opposite directions.

(d) They have different melting points.

Answer. (a)

121. Which of the following is not true of enantiomers?

(a) They have the same melting point.

(b) They have the same boiling point.

(d) They have the same specific rotation.

Answer. (d)

122. A and B are stereoisomers. They are nonsuperimposable and are mirror images of one another. Which of the following best describes the relationship between A and B?

(a) structural isomers

(b) enantiomers

(d) diastereomers

Answer. (b)

123. Which of the statements is correct about diastereomers?

(a) They are stereoisomers that are not enantiomers.

(b) They are a pair of identical isomers.

(d) All their asymmetric centers are the same.

Answer. (a)

124. Which of the following is/are optically inactive?

(a) a 50-50 mixture of R and S enantiomers

(b) a meso compound

(d) all the above

Answer. (d)

125. Hydrocarbons are

(a) Composed of carbon and hydrogen

(b) Composed of carbon, hydrogen, and oxygen

(d) Composed of carbon and nitrogen

Answer. (a)

126. Hydrocarbons are

(a) insoluble in water

(b) composed of carbon and hydrogen

(d) None of these

Answer. (c)

127. Which of following statements is false about propane?

(a) all bond angles are 109.5°

(b) each carbon is sp3 hybridized

(d) the compound undergoes polymerization to give polypropylene.

Answer. (d)

128. Which of the following is a correct name according to the IUPAC rules?

(a) 2-Methylcyclohexane

(b) 2-Ethyl-2-methylpentane

(d) 3-Ethyl-2-methylpentane

Answer. (d)

129. A tertiary carbon is bonded directly to :

(a) 2 hydrogens

(b) 3 carbons

(d) 4 carbons

Answer. (b)

130. What type of an alkyl group is an isobutyl group?

(a) primary

(b) secondary

(d) none of these

Answer. (a)

131. Which molecular formula indicates 2-methylpentane?

(a) C₅H₁₂

(b) C₆H₁₄

(d) C₆H₁₂

Answer. (b)

132. Which molecular formula indicates 2,2,4-trimethylhexane?

(a) C₉H₂₀

(b) C₉H₁₈

(d) C₈H₁₆

Answer. (a)

133. How many isomers are possible for butane?

(a) 2

(b) 3

(d) 5

Answer. (a)

134. How many isomers are possible for 2-methylpropane?

(a) 2

(b) 3

(d) 5

Answer. (a)

135. How many isomers are possible for pentane?

(a) 2

(b) 3

(d) 5

Answer. (b)

136. How many isomers are possible for hexane?

(a) 4

(b) 5

(d) 7

Answer. (b)

137. How many isomers are possible for heptane?

(a) 9

(b) 10

(d) 12

Answer. (a)

138. Marsh gas mainly contains

(a) CH₂=CH₂

(b) CH₄

(d) CHCl₃

Answer. (b)

139. Which statement is false?

(a) Many alkanes are soluble in water.

(b) All alkanes have a lower density than water.

(d) All alkanes burn.

Answer. (a)

140. As the molecular weight of alkanes increases, how do the boiling point and melting point change?

(a) boiling point increases ; melting point increases.

(b) boiling point increases ; melting point increases.

(d) boiling point increases ; melting point increases sequentially for alkanes over four carbons.

Answer. (d)

141. The branching of alkanes that produces symmetrical structures :

(a) raises the boiling point ; raises the melting point

(b) raises the boiling point ; lowers the melting point

(d) lowers the boiling point ; raises the melting point

Answer. (a)

142. How does the melting point of propane and ethane compare?

(a) the melting point of propane is greater.

(b) the melting point of ethane is greater.

(d) no relationship exists among these alkanes and their melting points.

Answer. (b)

143. How do the boiling points of butane, propane, and ethane compare?

(a) the boiling point of ethane is greatest.

(b) the boiling point of butane is greatest.

(d) there is no relationship among these three alkanes and their boiling points.

Answer. (b)

144. Which of the following alkanes will have the highest boiling point?

(a) n-Octane

(b) Isopentane

(d) Neopentane

Answer. (a)

145. Which of the following alkanes will have the lowest boiling point?

(a) n-Heptane

(b) Isopentane

(d) Neopentane

Answer. (d)

146. Methane can be prepared by :

(a) the reaction of iodomethane with sodium in dry ether

(b) the reaction of methanol with concentrated H2SO4

(d) the reaction of sodium ethanoate with soda-lime

Answer. (d)

147. Which of the following reactions can be used to prepare alkanes?

(a) Corey-House synthesis

(b) Williamson synthesis

(d) None of these

Answer. (a)

148. Which of the following reactions can be used to prepare alkanes?

(a) Wurtz reaction

(b) Wolf-kishner reduction

(d) All of these

Answer. (d)

149. Kolbe's electrolysis of sodium butyrate gives

(a) C₈H₁₆

(b) C₆H₁₄

(d) C₆H₁₂

Answer. (b)

150. Which of the following classes of compounds is unreactive toward sulfuric acid?

(a) Alkanes

(b) Alcohols

(d) Alkynes

Answer. (a)

151. Which of the following compounds does not dissolve in concentrated H2SO4 on warming?

(a) n-Hexane

(b) Diethyl ether

(d) Aniline

Answer. (a)

152. 2,3-Dimethyl-2-butene undergoes catalytic hydrogenation to give

(a) 2,3-Dimethylbutane

(b) 2-Methylpentane

(d) 3-Methylpentane

Answer. (a)

153. Why is the halogenation of alkanes considered a chain reaction?

(a) it occurs quickly.

(b) it occurs without the generation of intermediates.

(d) the reaction allows long chains of halogenated alkanes to be formed.

Answer. (c)

154. The chlorination of methane to give CCl4 is an example of

(a) an electrophilic addition

(b) a free-radical substitution

(d) an electrophilic substitution

Answer. (b)

155. In the chlorination of alkanes, the first step in which chlorine free radicals are produced is called :

(a) initiation

(b) activation

(d) deactivation

Answer. (a)

156. Chlorine free radicals react with methane by :

(a) donating their free-radical electron to methane to form chloromethane.

(b) abstracting a hydrogen atom from methane, and producing HCl and a methyl radical.

(d) forming a carbonium ion intermediate that rapidly dissociates to form chloromethane.

Answer. (b)

157. Which halogen does not appreciably react with methane in a free-radical substitution reaction?

(a) chlorine

(b) bromine

(d) fluorine

Answer. (c)

158. What product is formed in the free-radical bromination of methane?

(a) bromomethane

(b) dibromomethane

(d) all of these

Answer. (d)

159. Chlorination of an alkane as compared to bromination proceeds

(a) at a slower rate

(b) at a faster rate

(d) with equal or different rate depending upon the source of alkane.

Answer. (b)

160. How many monochlorinated isomers would result from the reaction of chlorine with n-butane in the presence of UV light?

(a) 2

(b) 4

(d) 8

Answer. (a)

161. How many monochlorination products are possible in the reaction of 2,2- dimethylbutane with chlorine in the presence of ultraviolet light?

(a) 2

(b) 3

(d) 5

Answer. (a)

162. A compound of formula C3H8 does not react with bromine in CCl4 in the dark. The compound could be

(a) Alkane

(b) Cycloalkane

(d) Cycloalkene

Answer. (a)

163. The combustion of Pentane produces :

(a) Pentene

(b) HCl + H₂O

(d) CO₂ + H₂O

Answer. (d)

164. The combustion of one mole of propane, C₃H₈, produces how many moles of H₂O?

(a) 2

(b) 3

(d) 5

Answer. (c)

165. The major carbon compound formed from the incomplete combustion of a hydrocarbon in air is

(a) carbon dioxide

(b) carbon monoxide

(d) alkyl chains

Answer. (b)

166. The thermal decomposition of alkanes in the absence of air is called :

(a) Combustion

(b) Oxidation

(d) Hydrogenation

Answer. (c)

167. LPG (Household cooking gas) is mainly a mixture of

(a) Methane + Ethane

(b) Acetylene + O₂

(d) Acetylene + H₂

Answer. (c)

168. What type of bonding is most important in CH₃CH₂CH₂CH₂CH₂CH₃?

(a) ionic

(b) hydrogen

(d) polar

Answer. (c)

169. What is the name given to a compound containing only carbons and hydrogens and having the maximum number of hydrogens in the molecule?

(a) alkene

(b) unsaturated hydrocarbon

(d) alkyne

Answer. (c)

170. Which of the following is the best description of propane, CH₃CH₂CH₃, at room temperature?

(a) liquid, soluble in H₂O

(b) gas, soluble in gasoline

(d) gas, soluble in water

Answer. (b)

171. Choose the correct hybridization for the atom indicated in the molecule below.

(a) sp

(b) sp2

(d) none of these

Answer. (c)

172. Which of the following has the greatest solubility in CH₃CH₂CH₂CH₃?

(a) CH₃OH

(b) CH₃NH₂

(d) (CH₃)₃CH

Answer. (d)

173. Consider the three isomeric alkanes n-hexane, 2,3-dimethylbutane, and 2- methylpentane. Which of the following correctly lists these compounds in order of increasing boiling point?

(a) 2,3-dimethylbutane < 2-methylpentane < n-hexane

(b) 2-methylpentane < n-hexane < 2,3-dimethylbutane

(d) n-hexane < 2-methylpentane < 2,3-dimethylbutane

Answer. (a)

174. The eclipsed and staggered forms of ethane are said to differ in .

(a) molecular formula

(b) configuration

(d) constitution

Answer. (c)

175. Octane number is related to

(a) Gasoline

(b) Kerosene oil

(d) Lubricating oil

Answer. (a)

176. A knocking sound is produced in the engine when the fuel

(a) Burns fast

(b) contains lubricating oil

(d) contains water

Answer. (a)

177. The octane rating of gasoline provides information on

(a) its antiknock properties

(b) its ignition properties

(d) its percentage content of isooctane

Answer. (a)

178. In any fuel, the percentage by volume of isooctane in a mixture of isooctane and n-heptane which will knock under same conditions as the fuel being tested, is called :

(a) Cracking

(b) Iodine number

(d) Octane number

Answer. (d)

179. Which of the following compounds is assigned the Octane Number of zero :

(a) n-Octane

(b) 2,3,3-Trimethylpentane

(d) 2,2,4-Trimethylpentane

Answer. (c)

180. Which of the following compounds is assigned the Octane Number of 100 :

(a) n-Heptane

(b) 2,3,3-Trimethylpentane

(d) 2,2,4-Trimethylpentane

Answer. (d)

181. Gasoline with an octane number of 90 is equivalent in knocking characteristics to a mixture of heptane and isooctane of the following composition

(a) 20% heptane + 80% isooctane

(b) 90% heptane + 10% isooctane

(d) 10% heptane + 90% isooctane

Answer. (d)

182. A fuel with octane number 90 means it is as good as a mixture of :

(a) 90% Isooctane + 10% n-heptane

(b) 90% n-Heptane + 10% isooctane

(d) 2 Litre of 90% n-heptane + 2 litre of benzene

Answer. (a)

183. Which hydrocarbon molecule with eight carbons would produce the lowest octane number (i.e., the most knocking) when used as a fuel in automobile?

(a) 2-Methyl-3,3-dimethylpentane

(b) n-Octane

(d) 2-Methylheptane

Answer. (b)

184. Which of the following compounds is used as an antiknock compound?

(a) Ethyllithium

(b) Tetraethyllead

(d) Lead acetate

Answer. (b)

185. Which of the following methods can be used to increase the octane rating of gasoline?

(a) Adding branched-chain alkanes

(b) Adding tetraethyllead

(d) All of these

Answer. (d)

186. The carbon atoms involved in the double bond of an alkene are

(a) sp hybridized

(b) sp2 hybridized

(d) None of these

Answer. (b)

187. Which of the following compounds will show geometrical isomerism?

(a) Propene

(b) 2-Butene

(d) 2-Butyne

Answer. (b)

188. Which of the following compounds is most stable?

(a) Ethylene

(b) 2,3-Dimethyl-1-butene

(d) 2-Butene

Answer. (b)

189. In which solvent are alkenes most soluble?

(a) water

(b) ethyl alcohol

(d) carbon tetrachloride

Answer. (d)

190. Which statements about alkenes and alkanes of corresponding chain lengths is true?

(I) Alkenes have slightly lower melting points than alkanes

(II) Alkenes have slightly higher melting points than alkanes

(III) Alkenes have higher boiling points than alkanes

(IV) Alkenes have lower boiling points than alkanes

(a) I and III

(b) II and IV

(d) II and III

Answer. (a)

191. How do the melting points of trans isomers compare to the cis isomers for alkenes?

(a) cis isomers have higher melting points

(b) trans isomers have higher melting points

(d) no consistent trend is observed

Answer. (b)

192. Why do trans isomers of alkenes have lower boiling points than cis isomers?

(a) trans isomers have better symmetry

(b) cis isomers have better symmetry

(d) cis isomers are less polar

Answer. (c)

193. The major product of acid-catalyzed dehydration of 3-pentanol is :

(a) 1-Pentene

(b) 2-Methyl-1-butene

(d) 3-Methyl-1-butene

Answer. (c)

194. Ethylene is obtained from ethyl bromide by :

(a) Simple heating

(b) Hydrolysis

(d) Nucleophilic substitution

Answer. (c)

195. The dehydrohalogenation of 2-bromobutane with alcoholic KOH gives mainly

(a) 2-Butene

(b) 2-Butyne

(d) 1-Butyne

Answer. (a)

196. In the reaction of propene with HCl, H+ ion acts as the :

(a) electrophile

(b) carbonium ion

(d) carbanion

Answer. (a)

197. When bromine attacks the double bond in propene, which of the following ions is formed in the first stage of the attack?

(a)

(b)

(c)

(d)

Answer. (a)

198. In the reaction of ethylene with H2O in the presence of sulfuric acid, which one adds across the double bond first?

(a) H+

(b) H.

(d) sulfate ion

Answer. (a)

199. Why does a H+ ion attacking a carbon-carbon double bond add to the carbon with the least number of substituents?

(a) the reaction is resonance stabilized.

(b) the hybrid geometry favors this process.

(d) a more stable carbonium ion is generated.

Answer. (d)

200. Propene reacts with bromine to form 1,2-dibromopropane. This is an example of

(a) Nucleophilic addition

(b) Electrophilic addition

(d) Electrophilic substitution

Answer. (b)

201. Baeyer's reagent is

(a) dilute KMnO₄

(b) HCl + ZnCl₂

(d) NH₂NH₂

Answer. (a)

202. In the addition of HX to a double bond, the hydrogen goes to the carbon that already has more hydrogens is a statement of

(a) Hund's rule

(b) Markovnikov's rule

(d) Saytzeff rule

Answer. (b)

203. Markovnikov's addition of HBr is not applicable to

(a) Propene

(b) 1-butene

(d) 2-butene

Answer. (d)

204. In the reaction of CH₃CH₂CH=CH₂ with HCl, the H of the HCl will become attached to which carbon?

(a) C-1

(b) C-2

(d) C-4

Answer. (a)

205. Which of the following compounds will react most readily with bromine in CCl₄?

(a) CH₃CH₂CH₃

(b) (CH₃)₃CH

(d) (CH₃)₄C

Answer. (c)

206. The disappearance of the purple color of KMnO4 in its reaction with alkene is known as

(a) Markovnikov test

(b) Grignard test

(d) Wurtz test

Answer. (c)

207. Which of the following will give a negative test when treated with bromine in carbon tetrachloride?

(a) Butane

(b) 2-Butene

(d) 2-Butyne

Answer. (a)

208. Ethylene reacts with HI to give

(a) Iodoethane

(b) 2,2-Diiodoethane

(d) None of these

Answer. (a)

209. Which of the following reagents will react with propene?

(a) Hot alkaline KMnO4

(b) Sodium metal

(d) LiAlH4

Answer. (a)

210. Which of the following compounds will have zero dipole moment?

(a) cis-1,2-dibromoethylene

(b) 1,1-dibromoethylene

(d) all of these

Answer. (c)

211. 2-Methylpropene reacts with HBr to give

(a) tert-Butyl bromide

(b) Isobutane

(d) None of these

Answer. (a)

212. 2-Butene reacts with HBr to give

(a) 1-Bromobutane

(b) 2,3-Dibromobutane

(d) 2,2-Dibromobutane

Answer. (c)

213. Which of the following alkenes reacts with HBr in the presence of a peroxide to give anti-Markovnikov's product?

(a) 1-Butene

(b) 2,3-Dimethyl-2-butene

(d) 3-Hexene

Answer. (a)

214. Propene reacts with HBr in the presence of a peroxide to give

(a) n-Propyl bromide

(b) Allyl bromide

(d) Vinyl bromide

Answer. (a)

215. 2-Methylpropene reacts with HBr in the presence of peroxide to give

(a) A primary alkyl bromide

(b) A secondary alkyl bromide

(d) A vicinal dibromide

Answer. (a)

216. 2-Methyl-2-butene reacts with HBr in the presence of peroxide to give

(a) A primary alkyl bromide

(b) A secondary alkyl bromide

(d) A vicinal dibromide

Answer. (b)

217. Hydration of 2-methyl-1-propene (with H₂O/H₂SO₄) gives :

(a) CH₃CH₂CH₂OH

(b) (CH₃)₃COH

(d) (CH₃)₂CHOH

Answer. (b)

218. A compound reacts with steam in the presence of concentrated H₂SO₄ to give isopropyl alcohol. The compound could be

(a) Alkane

(b) Alkyne

(d) Allene

Answer. (c)

219. Propene reacts with Cl₂ in H₂O to give

(a) 1-Chloro-2-propanol

(b) 2-Chloro-2-propanol

(d) 2-Chloro-1-propanol

Answer. (a)

220. 1-Butene reacts with Cl2 in H2O to give

(a) 1-Chloro-2-butanol

(b) 2-Chloro-2-butanol

(d) 2-Chloro-1-butanol

Answer. (a)

221. Catalytic hydrogenation of 3-methyl-1-butene gives :

(a) Isobutane

(b) 2,2-Dimethylbutane

(d) 2,3-Dimethylbutane

Answer. (c)

222. Which of the following alkenes gives only acetic acid on oxidation with hot concentrated KMnO₄.

(a) Ethylene

(b) 1-Butene

(d) 2-Butene

Answer. (d)

223. Which of the following compounds will give only acetaldehyde on ozonolysis?

(a) 1-Butene

(b) Acetylene

(d) Ethylene

Answer. (c)

224. Which of the following alkenes will give a mixture of acetone and formaldehyde on ozonolysis?

(a) 2-butene

(b) 2-methyl-2-butene

(d) 2-methylpropene

Answer. (d)

225. Which of the following alkenes will give a mixture of acetone and acetaldehyde an ozonolysis?

(a) 1-butene

(b) 2-methyl-2-butene

(d) 2-methylpropene

Answer. (b)

226. A hydrocarbon, C6H12, on ozonolysis gives only one product which does not give silver mirror with Tollens' reagent. The hydrocarbon is

(a) 2,3-Dimethyl-2-butene

(b) 2-Hexene

(d) 3-Hexene

Answer. (a)

227. Combustion of an alkene with sufficient oxygen will produce

(a) carbon dioxide and water

(b) carbon monoxide and water

(d) only carbon monoxide

Answer. (a)

228. Which of the following are correct statements concerning unsaturated hydrocarbons?

(a) All unsaturated hydrocarbons are insoluble in water.

(b) All unsaturated hydrocarbons are soluble in nonpolar solvents.

(d) (a) & (c)

Answer. (d)

229. How many electrons are involved in a carbon-carbon double bond?

(a) 1

(b) 2

(d) 4

Answer. (d)

230. Which of the following statements about ethene, C₂H₄, is incorrect?

(a) The H–C–H bond angles are approximately 109.5°.

(b) There is a total of five sigma bonds.

(d) The H–C–H bond angles are approximately 120°.

Answer. (a)

231. Which of the following statements about propene, CH₃CH=CH₂, is correct?

(a) All nine atoms lie in the same plane.

(b) The compound has a cis and trans isomer.

(d) All the carbon atoms are sp2 hybridized.

Answer. (c)

232. Which of the following is capable of exhibiting cis-trans isomerism?

(a) 1-butene

(b) 1-pentene

(d) 2-butene

Answer. (d)

233. Which of the following is the most stable alkene?

(a) trans-3-hexene

(b) cis-3-hexene

(d) (Z)-3-hexene

Answer. (a)

234. Which of the alkyl chlorides listed below undergoes dehydrohalogenation in the presence of a strong base to give 2-pentene as the only alkene product?

(a) 1-chloropentane

(b) 2-chloropentane

(d) 1-chloro-2-methylbutane

Answer. (c)

235. What is the major product from the acid-catalyzed hydration of 2-methyl-2- pentene?

(a) 2-methylpentane

(b) 2-methyl-1-pentanol

(d) 2-methyl-3-pentanol

Answer. (c)

236. 1,2-Butadiene has

(a) only sp hybridized carbon atoms

(b) only sp2 hybridized carbon atoms

(d) sp, sp2, sp3 hybridized carbon atoms

Answer. (d)

237. How many σ (sigma) bonds are there in CH₂=CH—CH=CH₂?

(a) 3

(b) 6

(d) 12

Answer. (c)

238. Propadiene, CH₂=C=CH₂, is

(a) a planar compound

(b) a cumulated diene

(d) a conjugated diene

Answer. (b)

239. Which of the following compounds have planar molecules?

(a) 1,3-Butadiene

(b) Dimethyl ether

(d) Allene

Answer. (a)

240. Which of the following molecular formulas will correspond to an alkene with two double bonds?

(a) C₄H₁₀

(b) C₅H₁₂

(d) C₈H₁₆

Answer. (c)

241. 1,3-Butadiene reacts with bromine to mainly give

(a) 3,4-Dibromo-1-butene

(b) 4-Bromo-1-butene

(d) 1-Bromo-2-butene

Answer. (c)

242. What descriptive term is applied to the type of diene represented by 1,5- octadiene?

(a) conjugated diene

(b) cumulated diene

(d) alkynyl diene

Answer. (c)

243. What descriptive term is applied to the type of diene represented by 2,4- hexadiene?

(a) conjugated diene

(b) cumulated diene

(d) alkynyl diene

Answer. (a)

244. Which of the following statements are correct concerning delocalized electrons?

(a) Electrons do not belong to a single atom.

(b) Electrons are not confined to a bond between two atoms

(d) (a), (b) and (c)

Answer. (d)

245. What is the hybridization of the central carbon of allene (1,2-propadiene)?

(a) sp

(b) sp2

(d) p

Answer. (a)

246. What compound results from the 1,4-addition of one equivalent of HBr to 1,3-butadiene?

(a) 1-bromo-1-butene

(b) 2-bromo-2-butene

(d) 1-bromo-2-butene

Answer. (d)

247. Rank the following dienes in order of increasing stability :

trans-1, 3-pentadiene, cis-1,3-pentadiene, 1,4-pentadiene and 1,2-pentadiene. Answer. 1,2-pentadiene < 1,4-pentadiene < cis-1,3-pentadiene < trans-1,3- pentadiene

248. A triple bond consists of

(a) 2 sigma bonds and 1 pi bond

(b) 3 sigma bonds

(d) 3 pi bonds

Answer. (c)

249. The bond angles associated with the hybrid orbitals of a carbon involved in a triple bond is

(a) 180°

(b) 120°

(d) 45°

Answer. (a)

250. How many electrons are involved in a carbon-carbon triple bond?

(a) 1

(b) 2

(d) 6

Answer. (d)

251. Which of the following improperly describes the physical properties of an alkyne?

(a) relatively nonpolar

(b) nearly insoluble in water

(d) insoluble in most organic solvents

Answer. (d)

252. Which of the following statements correctly describes the general reactivity of alkynes?

(a) An alkyne is an electron-rich molecule and therefore reacts as a nucleophile.

(b) The σ bonds of alkynes are higher in energy than the bonds and are thus more reactive.

(d) Alkynes are generally more reactive than alkenes.

Answer. (d)

253. Which of the following describes a triple bond?

(a) two sigma bonds and two pi bonds

(b) one sigma bond and one pi bond

(d) one sigma bond and two pi bonds

Answer. (d)

254. What two atomic orbitals or hybrid atomic orbitals overlap to form the carbon-carbon σ bond in ethyne?

(a) sp3–sp3

(b) sp2–sp2

(d) sp–sp

Answer. (d)

255. Which of the following statements is not true about propyne, HC–C≡CH₃?

(a) It contains six sigma bonds.

(b) It contains three pi bonds.

(d) The C–C–C bond angle is 180°.

Answer. (b)

256. How many distinct terminal alkynes exist with a molecular formula of C₅H₈?

(a) 1

(b) 2

(d) 4

Answer. (b)

257. How many distinct internal alkynes exist with a molecular formula of C₆H₁₀?

(a) 1

(b) 2

(d) 4

Answer. (c)

258. Which is the correct order of decreasing acidity in the following compounds?

A. H₂O B. CH₃CH₃ C. NH₃ D. CH₂=CH₂ E. HC≡CH

(a) A > E > C > D > B

(b) A > E > D > B > C

(d) A > C > E > D > B

Answer. (a)

259. Which of the following compounds is the major product when 1-hexyne is treated with excess HBr?

(a) 1,1-dibromohexane

(b) 1,1-dibromohexene

(d) 2,2-dibromohexane

Answer. (d)

260. The reagent needed to convert 2-butyne to cis-2-butene is :

(a) H₂/Pt

(b) H₂/Lindlar’s catalyst

(d) Na/NH₃

Answer. (b)

261. Among the compounds water, 1-butyne, 2-butyne, and ethane, which are stronger acids than ammonia?

(a) 1-butyne and ethane

(b) water and 1-butyne

(d) 1-butyne and 2-butyne

Answer. (b)

262. What is the product when 3-heptyne reacts with the Lindlar catalyst?

(a) 2-methyl-2-heptene

(b) trans-3-heptene

(d) cis-3-hexene

Answer. (d)

263. In the addition of hydrogen bromide to alkynes, which of the following species is believed to be an intermediate?

(a) vinyl anion

(b) vinyl cation

(d) carbene

Answer. (b)

264. Starting with 2-butene, which of the following is the best method for preparing

2-butyne?

(a) HBr; H₂/Ni; Zn/H+

(b) HBr; Zn/H+; H₂/Ni

(d) Br₂/CCl₄; 2NaNH₂

Answer. (d)

265.

In the following hydrogenation reactions ;

The hybrid state of the carbon atom changes from (a)

(b)

(c)

(d)

Answer. (b)

266. Which of the following hydrocarbons has acidic hydrogens?

(a) 1-Butene

(b) 1-Butyne

(d) 2-Butyne

Answer. (b)

267. Lindlar's catalyst is

(a) LiAlH₄

(b) Pd/BaSO₄ in Quinoline

(d) HCl/ZnCl₂

Answer. (b)

268. The higher reactivity of an alkene or alkyne, as compared to an alkane, is due to

(a) sigma bonds

(b) pi bonds

(d) None of these

Answer. (b)

269. Which of the following statements about alkenes and alkynes is correct?

(a) Alkynes are reduced more readily than alkenes.

(b) Alkynes are reduced less readily than alkenes.

(d) Alkynes and alkenes can not be reduced.

Answer. (a)

270. Which of the following sequences regarding acid-strength is correct?

(a) HC≡CH > CH₃CH₂OH > CH₃COOH

(b) HC≡CH > CH₃COOH > CH₃CH₂OH

(d) CH₃COOH > CH₃CH₂OH > HC≡CH

Answer. (d)

271. 1,2-Dichloroethane reacts with excess of NaNH2 to form

(a) Vinyl chloride

(b) Ethylene

(d) Acetylene

Answer. (d)

272. Propyne is formed by

(a) Polymerization of acetylene

(b) Reaction of acetylene with methane

(d) Reaction of sodium acetylide with methyl chloride

Answer. (d)

273. Which of the following compounds on hydrolysis gives acetylene?

(a) CaC₂

(b) Mg₂C₃

(d) Cu2Cl₂

Answer. (a)

274. Which of the following compounds on hydrolysis gives propyne?

(a) CaC2

(b) Mg2C3

(d) Cu2Cl2

Answer. (c)

275. Which one of the following compounds will (a) decolorizes dilute cold KMnO₄ ; (b) decolorizes bromine water ; and (c) gives a white precipitate with ammoniacal AgNO3 solution.

(a) 1-Hexene

(b) 1-Hexyne

(d) 2-Hexyne

Answer. (b)

276. Ethylene and acetylene can be distinguished by using

(a) Bromine in CCl₄

(b) Tollens' reagent

(b) Baeyer's reagent

(d) Phenylhydrazine

Answer. (b)

277. 1-Butyne can be distinguished from 2-butyne by using

(a) potassium permanganate

(b) bromine in CCl₄

(d) chlorine in CCl₄

Answer. (c)

278. 1-Butyne reacts with

(a) NaNH₂

(b) Dil H₂SO₄ and HgSO₄

(d) All of these

Answer. (d)

279. Propyne can be converted to propene by using

(a) H2 + Lindlar's catalyst

(b) NH₂NH₂

(d) NH₂NH₂ + KOH

Answer. (a)

280. 2-Butyne undergoes catalytic hydrogenation in the presence of Lindlar's catalyst to give

(a) 2-Butene

(b) Butane

(d) 2-Methylpropene

Answer. (a)

281. Addition of two moles of HCl to propyne gives :

(a) 2,2-Dichloropropane

(b) 1,3-Dichloropropane

(d) None of these

Answer. (a)

282. Propyne reacts with aqueous H₂SO₄ in the presence of HgSO₄ to form

(a) acetone

(b) 1-propanol

(d) 2-propanol

Answer. (a)

283. Acetylene reacts with water in the presence of sulfuric acid and mercuric sulfate to give

(a) Acetone

(b) Acetic acid

(d) Acetaldehyde

Answer. (d)

284. Which of the following compounds will react with ammoniacal silver nitrate?

(a) 1-Butene

(b) 1-Butyne

(d) 2-Butyne

Answer. (b)

285. Which of the following compounds does not react with ammoniacal AgNO₃ solution?

(a) Acetylene

(b) 1-Butyne

(d) 2-Butyne

Answer. (d)

286. Which of the following compounds reacts with ammoniacal cuprous chloride to give a precipitate?

(a) 1-Butene

(b) 1-Butyne

(d) 2-Butyne

Answer. (b)

287. Ozonolysis of 2-butyne gives

(a) Formic acid

(b) Propanoic acid

(d) Butanoic acid

Answer. (c)

288. Which alkyne yields propanoic acid as the only product upon treatment with ozone followed by hydrolysis?

(a) 1-Butyne

(b) 2-Hexyne

(d) 3-Hexyne

Answer. (d)

289. When acetylene is passed through hot iron tube at 400°C, it gives

(a) Benzene

(b) Toluene

(d) Mesitylene

Answer. (a)

290. When propyne is passed through hot iron tube at 400°C, it gives

(a) Benzene

(b) Toluene

(d) Mesitylene

Answer. (d)

291. The monomer for Neoprene is

(a) Isoprene

(b) acrylonitrile

(d) 1,3-butadiene

Answer. (c)

292. A compound, C4H6, reacts with bromine and forms a white precipitate with ammoniacal silver nitrate solution. It reacts with dilute H2SO4 in the presence of mercuric sulfate to form 2-butanone. The compound could be

(a) 1-Butyne

(b) 1-Butene

(d) 2-Butene

Answer. (a)

293. Which of the following correctly ranks the cycloalkanes in order of increasing ring strain per methylene?

(a) cyclopropane < cyclobutane < cyclohexane < cycloheptane

(b) cyclohexane < cyclopentane < cyclobutane < cyclopropane

(d) cyclopentane < cyclopropane < cyclobutane < cyclohexane

Answer. (b)

294. Which of the following has two equatorial alkyl substituents in its most stable conformation?

(a) 1,1-dimethylcyclohexane

(b) cis-1,2-dimethylcyclohexane

(d) cis-1,4-diethylcyclohexane

Answer. (c)

295. Which one of the following is not a metal catalyst for the hydrogenation of an alkene?

(a) Pd

(b) Pt

(d) Ni

Answer. (c)

296. What is(are) the product(s) in the Pd-catalyzed hydrogenation of 1,2- dimethylcyclopentene?

(a) trans-1,2-dimethylcyclopentane

(b) cis-1,2-dimethylcyclopentane

(d) 1,1-dimethylcyclopentane

Answer. (b)

297. Which of the following is not a possible reaction of a carbocation?

(a) addition of a nucleophile

(b) rearrangement to a more stable carbocation

(d) loss of a β-hydrogen to form an alkene

Answer. (c)

298. Addition of HCl to 3-methyl-1-pentene gives two products. One of these is 2-chloro-3-methylpentane. What is the other product?

(a) 1-Chloro-3-methylpentane

(b) 3-Chloro-3-methylpentane

(d) 2-Chloro-2-methylpentane

Answer. (b)

299. Predict which of the following alkenes reacts the fastest with HCl?

(a) CH₃CH₂CH₂CH₂CH=CH₂

(b) cis-CH₃CH₂CH=CHCH₂CH₃

(d) (CH₃)₂C=CHCH₂CH₃

Answer. (d)

300. The hydroboration-oxidation reaction can be characterized as the

to an alkene.

(a) anti-Markovnikov syn addition of water

(b) anti-Markovnikov anti addition of water

(d) Markovnikov anti addition of water

Answer. (a)

301. A compound, C15H24, is reacted with excess hydrogen using a metal catalyst. One equivalent of the compound consumed three equivalents of hydrogen. How

many rings did the original compound have?

(a) 1 only

(b) 2 only

(d) None of these

Answer. (a)

302. The reaction of 1-butene with bromine, Br₂, in aqueous solution gives primarily

1- bromo-2-butanol. Identify the nucleophilic species in the reaction.

(a) Br₂

(b) Br–

(d) HOBr

Answer. (c)

303. Which brief statement most accurately describes why alkenes react the way they do?

(a) C=C double bonds are weak.

(b) A π bond is lost but a stronger σ bond is gained.

(d) C=C π bonds are attacked by nucleophiles.

Answer. (b)

304. Which of the following poisonous gas is formed when chloroform is exposed to light and air?

(a) Mustard gas

(b) Carbon monoxide

(d) Chlorine

Answer. (c)

305. Freon-12, CCl₂F₂, is used as a

(a) Local anesthetic

(b) Dry-cleaning agent

(d) Disinfectant

Answer. (c)

306. Which of the following compounds has been suggested as causing depletion of the ozone layer in the upper stratosphere?

(a) CH₄

(b) CCl₂F₂

(d) CH₂Cl₂

Answer. (b)

307. Which of the following reagents cannot be used to prepare an alkyl chloride from an alcohol?

(a) HCl + ZnCl₂

(b) SOCl₂

(d) PCl₅

Answer. (c)

308. 2-Propanol reacts with KBr and concentrated H2SO4 to give

(a) 1-Bromopropane

(b) 1,2-Dibromopropane

(d) 2,2-Dibromopropane

Answer. (c)

309. The best way to prepare 1,2-Dibromoethane is to treat :

(a) Ethylene with Br2

(b) Acetylene with excess of HBr

(d) 1,2-Dichloroethane with Br2

Answer. (a)

310. Alkyl halides undergo

(a) Electrophilic substitution reactions

(b) Electrophilic addition reactions

(d) Nucleophilic addition reactions

Answer. (c)

311. n-Propyl iodide reacts with sodium ethoxide to give :

(a) CH₃CH₂OCH₂CH₃

(b) CH₃CH₂OCH₂CH₂CH₃

(d) CH₃OCH₂CH₂CH₃

Answer. (b)

312. 1-Bromobutane reacts with alcoholic KOH to mainly give

(a) 1-Butene

(b) 2-Butene

(d) 2-Butanol

Answer. (b)

313. 2-Bromobutane reacts alcoholic KOH to mainly give

(a) 1-Butene

(b) 2-Butene

(d) 2-Butanol

Answer. (b)

314. Isopropyl bromide reacts with alcoholic KOH to give

(a) Propene

(b) Isopropyl alcohol

(d) n-Propyl alcohol

Answer. (a)

315. 2,2-Dichloropropane reacts with aqueous KOH to give

(a) 2,2-Propanediol

(b) Propanal

(d) Propene

Answer. (c)

316. 1,1-Dichloropropane reacts with aqueous KOH to give

(a) 1,1-Propanediol

(b) Acetaldehyde

(d) Propyne

Answer. (b)

317. Which of the following compounds will not give a white precipitate with alcoholic AgNO₃.

(a) Bromobenzene

(b) 1-Bromopropane

(d) 2-Bromopropane

Answer. (a)

318. Which of the following compounds will give a white precipitate with alcoholic AgNO₃?

(a) Vinylbenzene

(b) Chlorobenzene

(d) Allyl chloride

Answer. (d)

319. Carbylamine test involves heating a mixture of

(a) alcoholic KOH, methyl iodide, and sodium metal

(b) alcoholic KOH, methyl iodide, and primary amine

(d) alcoholic KOH, methyl alcohol, and primary amine

Answer. (c)

320. When chloroform is heated with aqueous NaOH, it gives

(a) Formic acid

(b) Sodium formate

(d) Sodium acetate

Answer. (b)

321. Which alkyl halides react most readily by nucleophilic substitution?

(a) CH₃CH₂Cl

(b) CH₃CH₂I

(d) CH₃CH₂F

Answer. (b)

322. Which of the following factors influence whether a reaction will proceed by an S_N1, S_N2, E1, or E2 mechanism?

(a) Structure of the alkyl halide

(b) Solvent

(d) Nature of the nucleophile

(e) All of these

Answer. (e)

323. Which compound reacts most rapidly by an S_N1 mechanism?

(a) Methyl chloride

(b) Isopropyl chloride

(d) tert-Butyl chloride

Answer. (d)

324. Which of the following compounds would react most rapidly in an SN2 reaction?

(a) CH₃CH₂I

(b) CH₂=CH–I

(d) (CH₃)₃CI

Answer. (a)

325. There are 8 isomers that have the molecular formula C5H11Br. How many of these are tertiary alkyl bromides?

(a) 1

(b) 2

(d) 8

Answer. (a)

326. Which of the following statements is correct for a saturated alkyl halide?

(a) the C–X bond results from overlap of the s orbital of carbon and the p orbital of the halogen (X)

(b) the C–X bond results from overlap of the p orbital of carbon and the p orbital of the halogen (X)

orbital of the halogen (X)

(d) the C–X bond results from overlap of the sp2 orbital of carbon and the p

orbital of the halogen (X)

Answer. (c)

327. Which of the following best describes the carbon-chlorine bond of an alkyl chloride?

(a) nonpolar; no dipole

(b) polar; δ+ at carbon and δ– at chlorine

(d) ionic

Answer. (b)

328. Which of the following is a secondary alkyl halide?

(a) CH₃Br

(b) (CH₃)₃CBr

(d) (CH₃)₂CHCH₂Br

Answer. (c)

329. How should CH₃CHClCH₂CH₃ be classified?

(a) primary alkyl halide

(b) secondary alkyl halide

(d) quarternary alkyl halide

Answer. (b)

330. Which of the following will have the lowest boiling point?

(a) CH₃Cl

(b) CH₄

(d) CHCl₃

Answer. (b)

331. Which of the following is not correct concerning substitution and elimination reactions of alkyl halides?

(a) The electrophile replaces the leaving group.

(b) Compounds containing electron-donating groups bonded to an sp3 hybridized carbon undergo substitution and elimination reactions.

(d) (a) and (b)

Answer. (d)

332. Which of the following statements concerning S_N2 reactions of alkyl halides is not correct?

(a) The rate of reaction depends on the concentration of the nucleophile.

(b) The rate of reaction depends on the concentration of the alkyl halide.

(c) The rate of reaction of a particular alkyl bromide depends on the steric accessibility of the carbon of the C-Br bond.

(d) All alkyl iodides react more rapidly than all alkyl chlorides.

Answer. (d)

333. Which of the following correctly reflects relative stabilities of carbocations?

(a) 3° allylic > 2° > 1° benzylic

(b) methyl > 2° benzylic > 3°

(d) 2° allylic > 2° > vinyl

Answer. (d)

334. Which of the following species is most reactive in a S_N2 reaction?

(a) CH₃CH₂Cl

(b) CH₃CH₂Br

(d) CH₃CH₂F

Answer. (c)

335. Which of the following is the best leaving group?

(a) F–

(b) Cl–

(d) I–

Answer. (d)

336. Which of the following is the strongest nucleophile in an aqueous solution?

(a) HO–

(b) Cl–

(d) I–

Answer. (d)

337. Which of the following is the best nucleophile in water?

(a) I–

(b) CH₃SCH₃

(d) Cl–

Answer. (a)

338. Which of the following compounds will undergo an SN2 reaction most readily?

(a) (CH₃)₃CCH₂I

(b) (CH₃)₃CCl

(d) (CH₃)₂CHCH₂CH₂CH₂I

Answer. (d)

339. Which of the following is the rate law for S_N1 mechanisms?

(a) Rate = k[Alkyl Halide] [Nucleophile]

(b) Rate = k[Nucleophile]

(d) Rate = k1[Alkyl Halide] + k2[Nucleophile]

Answer. (c)

340. Which of the following factors has no effect on the rate of S_N1 reactions?

(a) the nature of the alkyl halide

(b) the nature of the leaving group

(d) the concentration of the nucleophile

Answer. (d)

341. Which is the most reactive alkyl halide in a S_N1 reaction?

(a) CH₃F

(b) CH₃Br

(d) CH₃Cl

Answer. (c)

342. Which of the following halides is most reactive in an E2 reaction with sodium

methoxide?

(a) (CH₃)₃CCH₂I

(b) (CH₃)₂CHCHICH₃

(d) (CH₃)₂CHCH₂Cl

Answer. (b)

343. Which of the following halides is least reactive in an E2 reaction with sodium methoxide?

(a) (CH₃)₃CCH₂I

(b) (CH₃)₂CHCHICH₃

(d) (CH₃)₂CHCH₂Cl

Answer. (a)

344. Dehydrohalogenation of 2-bromobutane in the presence of a strong base proceeds via which of the following mechanistic pathways?

(a) S_N1

(b) S_N2

(d) E2

Answer. (d)

345. Which of the alkyl chlorides listed below undergoes dehydrohalogenation in

the presence of a strong base to give 2-pentene as the only alkene product?

(a) 1-chloropentane

(b) 2-chloropentane

(d) 1-chloro-2-methylbutane

Answer. (c)

346. Predict the two most likely mechanisms for the reaction of 2-iodohexane with sodium ethoxide.

(a) S_N2 and S_N1

(b) E1 and E2

(d) E1 and S_N1

Answer. (c)

347. Predict the two most likely mechanisms which occur when 2-iodohexane is heated in ethanol.

(a) S_N2 and S_N1

(b) E1 and E2

(d) E1 and S_N1

Answer. (d)

348. Grignard reagents do not show any reaction with

(a) Alkoxyalkanes

(b) Alkanones

(d) Acyl halides

Answer. (a)

349. The Grignard reagent, CH₃CH₂MgBr, can be used to prepare

(a) Ethane

(b) 3-Ethyl-3-pentanol

(d) All of these

Answer. (d)

350.

Which is the best reagent to accomplish the following conversion?

(a) Conc. H₂SO₄

(b) Na

(d) Mg, then H₂O

Answer. (d)

351.

What is the major product of the following reaction?

(a) 1-Butanol

(b) Butanal

(d) Butanone

Answer. (c)

352. Ethylmagnesium iodide reacts with formaldehyde to give a product which on acid-hydrolysis forms :

(a) an aldehyde

(b) a primary alcohol

(d) a secondary alcohol

Answer. (b)

353. Ketones react with Grignard reagents to form an addition product which on hydrolysis gives a

(a) Primary alcohol

(b) Tertiary alcohol

(d) Ketal

Answer. (b)

354. n-Propylmagnesium bromide on treatment with carbon dioxide and further hydrolysis gives :

(a) Acetic acid

(b) Propanoic acid

(d) Formic acid

Answer. (c)

355. Which of the following compounds will react with methylmagnesium iodide followed by acid-hydrolysis to give ethyl alcohol?

(a) Ethylene

(b) Acetaldehyde

(d) Acetone

Answer. (c)

356. Which of the following gives a tertiary alcohol when treated with Grignard reagents?

(a)

(b)

(c)

(d) None of these

Answer. (c)

357. Which of the following compounds will react with methylmagnesium bromide to give tert-butyl alcohol?

(a) Acetyl chloride

(b) Acetone

(d) Acetaldehyde

Answer. (b)

358. Phenylmagnesium bromide reacts with acetaldehyde to form an addition product which undergoes acid-hydrolysis to give

(a) Diphenylcarbinol

(b) Benzyl alcohol

(d) Benzoic acid

Answer. (c)

359. Which of the following is the strongest base?

(a) HOMgBr

(b) H₂O

(d) CH₃MgBr

Answer. (d)

360. Which of the following is correct?

(a) When a Grignard reagent reacts with a ketone, the addition product is a primary alcohol.

(b) When a Grignard reagent reacts with a ketone, the addition product is a secondary alcohol.

(d) None of the above are correct.

Answer. (d)

361. Which of the following alcohols can be prepared by the reaction of methyl formate with excess Grignard reagent?

(a) 1-pentanol

(b) 2-pentanol

(d) 2-methyl-2-pentanol

Answer. (c)

362. The number of structural isomers of alcohols with molecular formula C3H7OH is

(a) 5

(b) 4

(d) 2

Answer. (d)

363. The number of structural isomers of alcohols with molecular formula C4H9OH is

(a) 5

(b) 4

(d) 6

Answer. (b)

364. Why do alcohols have boiling points much higher than hydrocarbons of similar molecular weight?

(a) Alcohols have greater van der Waals attraction forces.

(b) Alcohol molecules have greater molecular symmetry.

(d) Alcohols must overcome greater ionic forces in the process of volatilization.

Answer. (c)

365. The high boiling points of alcohols, as compared to the corresponding alkanes, are due to

(a) Hydrogen bonding

(b) Heavy oxygen atom

(d) None of these

Answer. (a)

366. Which of the following has the highest boiling point?

(a) diethyl ether

(b) n-Butyraldehyde

(d) n-Butyl alcohol

Answer. (d)

367. Which of the following has the highest boiling point?

(a) CH₃CH₂CH₂CH₂Cl

(b) HOCH₂CH₂CH₂CH₂OH

(d) CH₃CH₂OCH₂CH₃

Answer. (b)

368. Which of the following compounds has the highest boiling point? (a)

(b) CH₃CH₂CH₂OH

(c)

(d) CH₃CH₂OCH₃

Answer. (b)

369. Which of the following has the highest boiling point?

(a) CH₃CH₂OH

(b) CH₃CH₂CH₂CH₂OH

(d) CH₃CH₂CH₂OH

Answer. (b)

370. Rank the following substances in order of increasing boiling point (lowest → highest):

(1) CH₃CH₂CH₂CH₂OH, (2) (CH₃)₂CHOCH₃, (3) (CH₃)₃COH

(a) (1) < (2) < (3)

(b) (2) < (1) < (3)

(d) (3) < (2) < (1)

Answer. (c)

371. Which of the following compounds is the least soluble in water?

(a) HOCH₂CH₂OH

(b) CH₃CH₂CH₂OH

(d) CH₃CH₂CH₂CH₂OH

Answer. (d)

372. Methanol is known as :

(a) Rubbing alcohol

(b) Grain alcohol

(d) Denatured alcohol

Answer. (c)

373. Rectified spirit is

(a) 100% Ethanol

(b) 90% Ethanol

(d) 95% Ethanol

Answer. (d)

374. Grain alcohol is another name for

(a) Methyl alcohol

(b) Isopropyl alcohol

(d) n-Propyl alcohol

Answer. (c)

375. Lucas reagents is

(a) HCl/NaNO2

(b) H2/Pd

(d) H2/Pd/BaSO4

Answer. (c)

376. Lucas test is used to determine the type of

(a) alcohols

(b) acids

(d) carbohydrates

Answer. (a)

377. Which of the following gives positive Iodoform test :

(a) 1-Propanol

(b) 2-Propanol

(d) None of these

Answer. (b)

378. Which of the following reagents will replace –OH group by a halogen atom?

(a) HOCl

(b) Br₂

(d) I₂

Answer. (c)

379. The compound which reacts most readily with Lucas reagent is

(a) CH₃CH₂Cl

(b) (CH₃)₂CHOH

(d) (CH₃)₃COH

Answer. (d)

380. Which of the following compounds reacts slowest with Lucas reagent at room temperature?

(a) 1-butanol

(b) 2-propanol

(d) 2-methyl-2-propanol

Answer. (a)

381. Which of the following compounds will react fastest with Lucas reagent?

(a) 1-propanol

(b) 2-methyl-1-propanol

(d) 2-methyl-2-propanol

Answer. (d)

382. Which of the following compounds reacts fastest with HBr?

(a) 1-propanol

(b) 2-methyl-1-propanol

(d) 2-methyl-2-propanol

Answer. (d)

383. When ethanol is treated with sodium metal :

(a) Sodium ethoxide is formed

(b) The sodium is oxidized

(d) All these occur

Answer. (d)

384. Which of the following alcohols will give a yellow precipitate of iodoform with iodine and dilute NaOH solution?

(a) 1-Propanol

(b) 2-Propanol

(d) 2-Methyl-2-propanol

Answer. (b)

385. Ethyl alcohol can react with concentrated H2SO4 to give

(a) Ethylene

(b) Diethyl ether

(d) All of these

Answer. (d)

386. Ethanol on heating with concentrated H2SO4 at 170°C gives

(a) ethylene

(b) ethyl hydrogen sulfate

(d) diethyl sulfate

Answer. (a)

387. The major product of acid-catalyzed dehydration of 2-butanol is :

(a) 2-Butene

(b) 2-Butyne

(d) 1-Butyne

Answer. (a)

388.

Which is the best reagent for carrying out the following conversion?

(a) LiAlH₄

(b) Conc H₂SO₄

(d) NaOH

Answer. (b)

389. Which of the following reaction mixtures will give an organic product which is ionic?

(a) CH₃CH₂OH + PCl₅

(b) CH₃CH₂OH + KBr + H₂SO₄

(d) CH₃CH₂OH + SOCl₂

Answer. (c)

390. Hydroboration-oxidation of propene gives :

(a) Isopropyl alcohol

(b) n-Propyl alcohol

(d) tert-Butyl alcohol

Answer. (b)

391. Hydroboration-oxidation of 2-Methylpropene gives

(a) 2-Methyl-2-propanol

(b) 1,2,3-Propanetriol

(d) 1,2-Propanediol

Answer. (c)

392. Which of the following compounds will not be easily oxidized?

(a) Primary alcohol

(b) Secondary alcohol

(d) Aldehyde

Answer. (c)

393. Which of the following is most resistant to oxidation?

(a) CH₃CH₂OH

(b) (CH₃)₂CHOH

(d) (CH₃)₃COH

Answer. (d)

394. Oxidation of a primary alcohol with produces

(a) a carboxylic acid

(b) an ether

(d) an ester

Answer. (a)

395. Oxidation of a secondary alcohol with K2Cr2O7/H+ produces

(a) a carboxylic acid

(b) a ketone

(d) an ester

Answer. (b)

396. Isopropyl alcohol reacts with acidic sodium dichromate to give

(a) Acetaldehyde

(b) Acetic acid

(d) Acetone

Answer. (d)

397. Isopropyl alcohol can be converted to acetone by treatment with

(a) HCl/ZnCl₂

(b) Na₂Cr₂O₇/H₂SO₄

(d) LiAlH₄

Answer. (b)

398. Which of the bonds in Ethyl alcohol (CH3CH2OH) will undergo heterolytic bond fission most readily?

(a) O–H

(b) C–H

(d) C–C

Answer. (a)

399. The mechanism of dehydration of an alcohol to give an alkene involves formation of :

(a) Carbonium ions

(b) Carbanions

(d) Carbenes

Answer. (a)

400. The mechanism of dehydration of an alcohol to give an ether involves formation of :

(a) Carbonium ions

(b) Carbanions

(d) Carbenes

Answer. (a)

401. The acid-catalyzed dehydration mechanism for alcohols is best described as a(n) :

(a) E1

(b) E2

(d) S_N2

Answer. (a)

402. When ethanol is heated with concentrated H₂SO₄, a gas is produced. Which of the following compounds is formed when this gas is treated with bromine in CCl₄?E2

(a) Bromomethane

(b) 1,2-Dibromoethane

(d) 1,1,2,2-Tetrabromoethane

Answer. (b)

403. What is the functional group in an alcohol?

(a) Carbon-carbon double bond

(b) NH₂

(d) COOH

Answer. (c)

404. What is the IUPAC name for the following structure?

CH₃CH(CH₃)CH₂CH(OH)CH₃

(a) 4-methyl-2-pentanol

(b) 2-methyl-2-hexanol

(d) 2-methyl-3-pentanol

Answer. (a)

405. Explain why the water molecule has a bent shape and a bond angle less than 109.5°.

Answer. The electron repulsion between the two lone pairs of electrons on the oxygen of water causes the O–H bonds to squeeze close together.

406. Which of the following compounds does not have the molecular formula C6H14O?

(a) 2-hexanol

(b) 3-methyl-2-pentanol

(d) cyclohexanol

Answer. (d)

407. Which of the following is a secondary alcohol?

(a) 3-ethyl-2-methyl-1-pentanol

(b) 3-ethyl-2-methyl-2-heptanol

(d) 1-hexanol

Answer. (c)

408. Which of the following is sec-butyl alcohol?

(a) CH₃CH₂CH₂CH₂OH

(b) CH₃CH(OH)CH₂CH₃

(d) (CH₃)₂CHOH

Answer. (b)

409. What is the hybridization of the oxygen atom in CH3CH2OH?

(a) sp

(b) 4sp3

(d) sp3

Answer. (d)

410. Where are the two lone pairs of electrons of the oxygen atom in an alcohol molecule located?

(a) in two p orbitals

(b) in two sp orbitals

(d) in two sp3 orbitals

Answer. (d)

411. What is the strongest intermolecular force present in liquid ethanol?

(a) induced dipole-induced dipole

(b) dipole-dipole, specifically hydrogen bonding

(d) ion-dipole

Answer. (b)

412. Which of the following is the best method for preparing CH3Br?

(a) CH₃OH + Br–

(b) CH₃OH + HBr

(d) CH₃OH + NaBr

Answer. (b)

413. Which of the following reagents can be used to oxidize 1° alcohols to aldehydes?

(a) KMnO₄

(b) MnO₂

(d) PCC

Answer. (d)

12. What is the major product from the acid-catalyzed hydration of 2-methyl-2- pentene?

(a) 2-methylpentane

(b) 2-methyl-1-pentanol

(d) 2-methyl-3-pentanol

Answer. (c)

414. In cold countries ethylene glycol is added to water in car radiators. This helps to

(a) Reduce the viscosity

(b) Make water a better lubricant

(d) Lower the boiling point

Answer. (c)

415. Ethylene oxide undergoes acid-hydrolysis to form

(a) Ethylene glycol

(b) Formic acid

(d) Acetic acid

Answer. (a)

416. Ethylene glycol undergoes oxidation with hot acidic KMnO4 to form :

(a) Formic acid

(b) Formaldehyde

(d) Acetaldehyde

Answer. (a)

417. Ethylene glycol reacts with excess of PCl5 to give

(a) Chloroethane

(b) 1,2-Dichloroethane

(d) 1,3-Dichloroethane

Answer. (b)

418. 1,2-Ethanediol reacts with anhydrous zinc chloride to form

(a) Ethylene

(b) Acetaldehyde

(d) Ethyl chloride

Answer. (b)

419. When ethylene glycol is heated with concentrated HNO3, it forms

(a) Oxalic acid

(b) Ethylene oxide

(d) Diethylene glycol

Answer. (a)

420. Which of the following is used as an antifreeze?

(a) Ethylene glycol

(b) Glycerol

(d) Picric acid

Answer. (a)

421. When glycerol is heated with oxalic acid at 260°C, it gives

(a) 1,2-Propanediol

(b) Vinyl alcohol

(d) Allyl alcohol

Answer. (d)

422. When glycerol is heated with potassium hydrogen sulfate (KHSO4), it forms

(a) Acrolein

(b) Acetic acid

(d) Propionic acid

Answer. (a)

423. Glycerol on warming with a small amount of hydriodic acid gets converted to

(a) Propene

(b) 3-Iodopropene

(d) 2-Iodopropane

Answer. (b)

424. When glycerol is treated with a mixture of concentrated HNO₃ + H₂SO₄, it forms

(a) Nitroethane

(b) 1-Nitropropane

(d) 2-Nitropropane

Answer. (c)

425. In the manufacture of dynamite, one of the chemicals used is

(a) Glycerol

(b) Glycerol triacetate

(d) Glycerol triiodide

Answer. (c)

426. Which of the following compounds is least soluble in water?

(a) Glycerol

(b) Ethyl alcohol

(d) Ethyl chloride

Answer. (d)

427. Compound (A) reacts with sodium metal to form one mole of H₂. The compound (A) can be

(a) CH₃CH₂CH=CH₂

(b) HOCH₂CH₂CH₂CH₂OH

(d) CH₃CH₂CH₂CH₂OH

Answer. (b)

428. Ethers are

(a) Lewis acids

(b) Neutral

(d) Can not be predicted

Answer. (c)

429. Ethanol is isomeric with

(a) Dimethyl ether

(b) Ethanal

(d) Propanone

Answer. (a)

430. Diethyl ether and methyl propyl ether are

(a) Conformational isomers

(b) Metamers

(d) Enantiomers

Answer. (b)

431. The reaction of a sodium alkoxide with an alkyl halide is called

(a) Wurtz-Fittig reaction

(b) Perkin reaction

(d) Aldol condensation

Answer. (c)

432. Ethyl bromide reacts with sodium methoxide to form

(a) Diethyl ether

(b) Ethyl methyl ether

(d) n-Propyl alcohol

Answer. (b)

433. Ethyl alcohol reacts with concentrated H2SO4 at 140°C to form

(a) Acetone

(b) Ethylene

(d) Acetic acid

Answer. (c)

434. Ethers are kept in brown bottles because

(a) Brown bottles are cheaper than colorless clear bottles

(b) Ethers absorb moisture

(d) Ethers are oxidized to explosive peroxides

Answer. (d)

435. Ethers are stored in brown bottles. This is because on exposure to air and light ethers are converted to

(a) Peroxides

(b) Oxonium ions

(d) Electrophiles

Answer. (a)

436. Ethers can be freed from peroxides by treatment with

(a) Ferrous salt

(b) Sodium carbonate

(d) Sodium bicarbonate

Answer. (c)

437. Which of the following statements is false?

(a) Diethyl ether has been used as a general anesthetic

(b) Ethyl alcohol is present in all alcoholic beverages

(d) Ethylene glycol is a common antifreeze for automobiles

Answer. (c)

438. Ethers react with cold concentrated H2SO4 to form

(a) Oxonium salts

(b) Alkenes

(d) Zwitterions

Answer. (a)

439. Which of the following reagents readily react with ethyl methyl ether?

(a) NaOH

(b) Conc HI

(d) H₂O

Answer. (b)

440. Diethyl ether reacts with sodium metal to give

(a) Ethanol

(b) Sodium ethoxide

(d) Nothing happens

Answer. (d)

441. Diethyl ether on heating with excess concentrated HI gives

(a) Methyl iodide

(b) Isopropyl iodide

(d) n-Propyl iodide

Answer. (c)

442. Diethyl ether reacts with excess of hot concentrated HI to form

(a) CH₃CH₂I + CH₃CH₂OH

(b) Only CH₃CH₂OH

(d) Only CH₃CH₂I

Answer. (d)

443. Which is the best reagent to accomplish the following conversion?

CH₃CH₂OCH₂CH₃ CH₃CH₂Br

(a) Br₂ in CCl₄

(b) NaBr

(d) Conc HBr

Answer. (d)

444. Which of the following pairs of compounds will not form hydrogen bonds with each other?

(a) CH₃OH and CH₃CH₂OH

(b) CH₃SH and CH₃CH₂SH

(d) CH₃COOH and H₂O

Answer. (c)

445. The compound with the lowest boiling point is

(a) H₂O

(b) CH₃CH₂OH

(d) CH₃CH₂CH₃

Answer. (d)

446. Which of the following would have the highest boiling point?

(a) 1-Butanol

(b) Butane

(d) 1-Butyne

Answer. (a). Alcohols of the same chain length as alkanes, alkenes, and alkynes have higher boiling points due to their ability to hydrogen bond.

447. Which of the following would have the highest boiling point?

(a) Dimethyl ether

(b) Diethyl ether

(d) Diisopropyl ether

Answer. (d). Ethers follow the same trend as alkanes, so diisopropyl ether will have the highest boiling point because it has the highest molecular weight.

448. Which of the following functional group series is ranked according to increasing boiling points?

(a) diethyl ether, ethane, ethanol, ethanethiol

(b) ethane, ethanol, diethyl ether, ethanethiol

(d) diethyl ether, ethane, ethanethiol, ethanol

Answer. (c)

449. The following compounds have identical molecular weights. Which would have the lowest boiling point?

(a) 1-Methoxypropane

(b) 1-Butanol

(d) 2-Butanol

Answer. (a)

450. Cyclic ethers with three-membered ring are called

(a) Lactones

(b) Oxiranes

(d) Epoxy resins

Answer. (b)

451. Ethylene reacts with oxygen in the presence of silver catalyst at 300°C to form

(a) Diethyl ether

(b) Ethylene glycol

(d) Ethylene oxide

Answer. (d)

452. Ethylene oxide reacts with HBr to give

(a) 1-Bromoethanol

(b) Ethyl bromide

Answer. (c)

453. Acid-catalyzed hydrolysis of ethylene oxide yields

(a) CH₃CH₂OH

(b) HOCH₂CH₂OH

(d) HOCH₂CH₂CH₂OH

Answer. (b)

454. The product of the reaction of ethylene oxide with acidic methanol is

(a) CH₃OCH₂CH₂OH

(b) CH₃CH₂CH₂CH₂OH

(d) CH₃CH₂OCH₂CH₃

Answer. (a)

455. Ethylene oxide reacts with ammonia to give

(a) 1-Aminoethanol

(b) Ethylamine

(d) Acetamide

Answer. (c)

456. Which of the following is closest to the C–O–C bond angle in CH3–O–CH3?

(a) 180°

(b) 120°

(d) 90°

Answer. (c)

457. When dipentyl ether is treated with excess HI, through what type of mechanism(s) does the major product result?

(a) S_N2

(b) S_N1

(d) E2

Answer. (a)

458. Which of the following is not a property of thiols (RSH)?

(a) They are all solids

(b) They can be oxidized to disulfides

(d) They are weak acids

Answer. (a)

459. Thiols are alcohol analogs in which the oxygen has been replaced by sulfur (e.g., CH₃SH). Given the fact that the S–H bond is less polar than the O–H bond, which of the following statements comparing thiols and alcohols is correct?

(a) Hydrogen bonding forces are weaker in thiols.

(b) Hydrogen bonding forces are stronger in thiols.

(d) No comparison can be made without additional information.

Answer. (a)

460. Which of the following has the lowest boiling point?

(a) CH₃CH₂OH

(b) CH₃CH₂CH₂SH

(d) CH₃CH₂CH₂OH

Answer. (b)

461. Which of the following is least soluble in water?

(a) CH₃OH

(b) CH₃CH₂OH

(d) HOCH₂CH₂OH

Answer. (c)

462. n-Butyl bromide reacts with NaSH to give

(a) CH₃CH₂CH₂SH

(b) CH₃SCH₃

(d) CH₃CH₂SCH₂CH₃

Answer. (c)

463. The carbon atom of a carbonyl group is

(a) sp hybridized

(b) sp2 hybridized

(d) None of these

Answer. (b). Whenever carbon is bonded to three other atoms or groups, it uses

sp2 hybrid orbitals to form its bonds.

464. Which statement about the carbonyl group is NOT true?

(a) The carbonyl carbon is sp2 hybridized.

(b) The bond angles among the three atoms attached to the carbonyl carbon are 120°.

(d) The carbonyl group forms resonance structures.

Answer. (c)

465. Acetone contains

(a) nine σ bonds plus one π bond

(b) ten σ bonds

(d) nine π bonds plus one σ bond

Answer. (a)

466. Formalin is

(a) 10% solution of formaldehyde in water

(b) 20% solution of formaldehyde in water

(d) 80% solution of formaldehyde in water

Answer. (c)

467. Which of the following will have the highest boiling point?

(a) Propanone

(b) 2-Pentanone

(d) 2-Hexanone

Answer. (d). Boiling points increase with molecular weight. The higher the molecular weight, the higher is the boiling point. All of the given compounds are ketones. 2-Hexanone has the highest molecular weight.

468. Which of the following will have the highest boiling point?

(a) Methanal

(b) Ethanal

(d) Butanal

Answer. (d). The boiling points increase with molecular weight. All of the given

compounds are aldehydes. Butanal has the highest molecular weight.

469. What property of low-molecular weight aldehydes and ketones accounts for the magnitude of their boiling points?

(a) The ability to form strong H-bonds between their molecules.

(b) The ability of the carbonyl oxygen to form H-bonds with other carbonyl groups.

(d) The ability of the carbonyl group to attract electrophiles and form bonds.

Answer. (c)

470. Primary alcohols have boiling points that are the corresponding aldehydes.

(a) Lower than

(b) Higher than

Answer. (b). For compounds of similar molecular weights, boiling points increase with the degree of hydrogen bonding. Remember : Alcohols form strong hydrogen bonds and will boil at a higher temperature than the corresponding aldehydes.

471. The melting points of aldehydes and ketones tend to :

(a) decrease with increasing molecular weight.

(b) increase with increasing molecular weight.

(d) be unpredictable due to resonance.

Answer. (b)

472. Which action best accounts for the solubility of aldehydes and ketones in water?

(a) Polar interactions between solute molecules.

(b) H-bonding between solute molecules.

(d) H-bonding between solute and solvent molecules

Answer. (d)

473. Ketones are prepared by the oxidation of

(a) Primary alcohol

(b) Secondary alcohol

(d) None of these

Answer. (b)

474. Which of the following do you consider to be suitable for obtaining acetone

(CH₃COCH₃)?

(a) Heating CH₃CH₂CH₂OH with acidic Na₂Cr₂O₇

(b) Passing over heated copper

(d) Heating CH₃CH=CH₂ with dilute H₂SO₄

Answer. (b)

475. Cyclopentanol undergoes oxidation to give :

(a) Cyclopentene

(b) Cyclopentanone

(d) Cyclopentanal

Answer. (b)

476. Which statement about the carbonyl group of ketones and aldehydes is true?

I. It can attract nucleophiles.

II. It can attract electrophiles.

III. It tends to undergo addition reactions.

IV. It tends to undergo substitution reactions.

(a) I and III

(b) II and IV

(d) I, III, and IV

Answer. (c)

477. Which of the following compounds reacts with sodium bisulfite and ammoniacal silver nitrate solution?

(a)

(b)

(c)

(d)

Answer. (b)

478. Acetone reacts with HCN to form a cyanohydrin. It is an example of

(a) Electrophilic addition

(b) Electrophilic substitution

(d) Nucleophilic substitution

Answer. (c)

479. Which of the following reagents will react readily with both aldehydes and ketones?

(a) Grignard reagent

(b) Fehling's reagent

(d) Schiff's reagent

Answer. (a)

480. Boiling acetaldehyde (CH3CHO) reacts with chlorine gas to give (a)

(b)

(d) CHCl₃

Answer. (b)

481. The reaction of ethanal with one equivalent of methanol and a trace of an acid will give

(a) Acetal

(b) Hemiacetal

(d) Hemiketal

Answer. (b)

482. Acetone undergoes reduction with hydrazine in the presence of NaOH to form propane. This reaction is known as

(a) Clemmensen reduction

(b) Wolf-Kishner reduction

(d) Reformatsky reaction

Answer. (b)

483. Acetone undergoes reduction with zinc amalgam in HCl to form propane.

This reaction is known as

(a) Clemmensen reduction

(b) Wolf-Kishner reduction

(d) Aldol condensation

Answer. (a)

484. Cannizzaro reaction is not given by

(a) Formaldehyde

(b) Trimethylacetaldehyde

(d) Benzaldehyde

Answer. (c)

485. When formaldehyde is treated with 50% NaOH solution, it undergoes

(a) Cannizzaro reaction

(b) Wurtz reaction

(d) Hydrolysis

Answer. (a)

486. The reduction of a ketone

(a) always gives a primary alcohol

(b) always gives a secondary alcohol

(d) always gives a ketal

Answer. (b)

487. Reduction of acetaldehyde with H₂/Ni gives

(a) Ethyl alcohol

(b) Acetic acid

(d) Ethane

Answer. (a)

488. On reduction with LiAlH4, which of the following compounds could yield an optically active compound?

(a) Propanal

(b) Propanone

(d) Butanone

Answer. (d)

489. The reduction of cyclohexanone with LiAlH₄ (or NaBH₄) will give

(a) an alcohol

(b) an organic acid

(d) a hemiketal

Answer. (a)

490. Aldehydes undergo oxidation with KMnO₄/H+ to give

(a) Alcohols

(b) Acetals

(d) Acids

Answer. (d)

491. Oxidation of acetaldehyde with Na₂Cr₂O₇/H+ gives

(a) Ethylene glycol

(b) Acetic acid

(d) Acetone

Answer. (b)

492. A hydrazone will result from the reaction of hydrazine with

(a) a phenol

(b) an aldehyde

(d) an acid

Answer. (b)

493. Aldehydes can be distinguished from ketones by using

(a) Ammoniacal AgNO₃ solution

(b) Phenylhydrazine

(d) Thionyl chloride

Answer. (a)

494. The appearance of a silver mirror in Tollens' test indicates the presence of :

(a) an aldehyde

(b) a ketone

(d) an alkene

Answer. (a)

495. Acetaldehyde on treatment with Tollens' reagent gives a precipitate of

(a) Ag

(b) AgNO₃

(d) None of these

Answer. (a)

496. Which of the following compounds will give a positive test with Fehling's solution?

(a) Formaldehyde

(b) Acetone

(d) Acetic acid

Answer. (a)

497. Acetaldehyde on treatment with Fehling's solution gives a precipitate of

(a) Cu

(b) Cu₂O

(d) None of these

Answer. (b)

498. Which of the following will react with Fehling's solution giving a red precipitate?

(a) CH₃CH₂CHO

(b) CH₃CH₂OCH₂CH₃

(d)

Answer. (a)

499. Which of the following compounds will give an iodoform test?

(a) Benzoic acid

(b) Ethanol

(d) Methanol

Answer. (b)

500. Which of the following compounds does not give a positive iodoform test :

(a) Ethanol

(b) Ethanal

(d) Propanone

Answer. (c)

501. Which of the following compounds does not give iodoform test on treatment with

I2/NaOH?

(a) Ethanol

(b) Propanone

(d) Butanone

Answer. (d)

502. Which of the following compounds will give a positive iodoform test?

(a) Benzaldehyde

(b) 2-Pentanone

(d) 3-Pentanone

Answer. (b)

503. An organic compound (A), C₃H₈O, on oxidation gives (B), C₃H₆O. The compound (A) could be

(a) an aldehyde

(b) a ketone

(d) an ester

Answer. (c)

504. An organic compound (A), C₃H₈O, on oxidation gives (B), C₃H₆O. The compound (B) could be

(a) a carbonyl compound

(b) an alcohol

(d) an ether

Answer. (a)

505. An unknown compound gave a positive Tollens' test. Treatment of the unknown with I2/NaOH gave a solid which was identified as iodoform. The unknown was?

(a) Ethanal

(b) Acetone

(d) Acetophenone

Answer. (a)

506. A compound (A) gave a positive iodoform test, but did not reduce silver nitrate in ammonia solution. Compound (A) could be

Answer.

507. Which of the following characterizes the reactions of aldehydes and ketones?

(a) electrophilic addition

(b) electrophilic substitution

(d) nucleophilic addition; free radical addition

Answer. (d)

508. Why do aldehydes undergo nucleophilic addition reactions while esters undergo nucleophilic acyl substitution reactions?

(a) The carbonyl carbon of an ester is more electrophilic than that of an aldehyde.

(b) Aldehydes are more sterically hindered than esters.

(c) Once the nucleophile adds to an aldehyde, the tetrahedral intermediate is too sterically hindered to eliminate one of the attached groups.

(d) Once the nucleophile adds to an aldehyde, neither H− nor R− can be eliminated since they are strongly basic.

Answer. (d)

509. Which of the following reagents can be used to reduce acetaldehyde to ethyl alcohol?

(a) 1. LiAlH₄ / 2. H₃O+

(b) 1. NaBH₄ / 2. H₃O+

(d) All of these

Answer. (d)

510. What is the hybridization of the carbonyl oxygen in carboxylic acids?

(a) sp

(b) sp2

(d) s-sp2

Answer. (b)

511. What is the hybridization and geometry of the carbonyl carbon in carboxylic acids and their derivatives?

(a) sp3, tetrahedral

(b) sp2, trigonal planar

(d) sp3, trigonal planar

Answer. (b)

512. Organic compound (A), C₄H₈O, does not react with sodium or PCl₅. However, it reduces an alkaline solution of a copper (II) salt on heating.

Compound (A) could be

(a) an aldehyde

(b) a primary alcohol

(d) a secondary alcohol

Answer. (a)

513. Check the incorrect statement :

(a) Acetic acid is present in sour milk

(b) Formic acid is present in insect bites

(d) Citric acid is a tricarboxylic acid

Answer. (a)

514. In the conversion of wine to vinegar

(a) Ethanol is oxidized to acetic acid

(b) Ethanol is reduced to acetic acid

(d) Methanol is reduced to acetic acid

Answer. (a)

515. Vinegar is a

(a) 5% solution of acetic acid in water

(b) 25% solution of acetic acid in water

(d) 40% solution of formic acid in water

Answer. (a)

516. In succinic acid, HOOC(CH₂)_nCOOH, n is equal to

(a) 1

(b) 2

(d) 4

Answer. (b)

517. In adipic acid, HOOC(CH₂)_nCOOH, n is equal to

(a) 1

(b) 2

(d) 4

Answer. (d)

518. The compound in which hydrogen bonding is not possible is

(a) CH₃OCH₃

(b) H₂O

(d) CH₃COOH

Answer. (a)

519. Which compound has the highest boiling point?

(a) CH₃CH₃

(b) CH₃OCH₃

(d) CH₃COOH

Answer. (d)

520. When carboxylic acids and dicarboxylic acids have similar molecular weights, how do their melting points compare?

(a) Carboxylic acids have greater melting points.

(b) Dicarboxylic acids have greater melting points.

(d) No consistent trend exists.

Answer. (b)

521. The greater acidity of carboxylic acids compared to alcohols arises primarily from :

(a) the electron-donating effect of the hydroxyl group

(b) the electron-withdrawing effect of the carboxyl oxygen

(d) the resonance stability associated with the carboxylate ion

Answer. (d)

522. Which of the following statements is false about the acid-strength of acetic acid?

(a) Acetic acid is a stronger acid than monochloroacetic acid.

(b) Acetic acid is a stronger acid than propionic acid.

(d) Acetic acid is a weaker acid than formic acid.

Answer. (a)

523.

Arrange the following compounds in order of decreasing acidity :

(a) (1) > (2) > (3)

(b) (3) > (2) > (1)

(d) (2) > (1) > (3)

Answer. (b)

524. Which of the following is the strongest acid?

(a) Formic acid

(b) Trichloroacetic acid

(d) Trifluoroacetic acid

Answer. (d)

525. Which of the following is the strongest acid?

(a) Butanoic acid

(b) 2-Chlorobutanoic acid

(d) 4-Chlorobutanoic acid

Answer. (b)

526. Which of the following is the strongest acid in aqueous solution?

(a) CH₃COOH

(b) ClCH₂COOH

(d) Cl₂CHCOOH

Answer. (d)

527. Which is the strongest acid?

(a) CH₃COOH

(b) Cl₂CHCOOH

(d) Cl₃CCOOH

Answer. (d)

528. Which of the following compounds is most acidic?

(a) CH₃COOH

(b) ClCH₂COOH

(d) FCH₂COOH

Answer. (d)

529. Which of the following compounds is the strongest acid?

(a) CH₃COOH

(b) CH₃CH₂COOH

(d) CH₃CH₂CH₂COOH

Answer. (c)

530. Which of the following compounds is least acidic?

(a) CH3CH2COOH

(b) BrCH2CH2COOH

(c)

(d)

Answer. (a)

531. Which of the following compounds is most acidic?

(a) CH₃CH₂COOH

(b) BrCH₂CH₂COOH

(c)

(d)

Answer. (d)

532. Which of the following will give acetic acid on acid-hydrolysis?

(a) Ethyl acetate

(b) Acetone

(d) Lactic acid

Answer. (a)

533. Propanenitrile undergoes acid-hydrolysis to give

(a) Formic acid

(b) Propionic acid

(d) Butyric acid

Answer. (b)

534. The characteristic reaction of carboxylic acids is :

(a) electrophilic addition

(b) electrophilic substitution

(d) nucleophilic substitution

Answer. (d)

535. Which of the following compounds will react with Tollens' reagent to give metallic silver?

(a) Formic acid

(b) Ethyl alcohol

(d) Acetone

Answer. (a)

536. Which of the following compounds on treatment with NaHCO3 will liberate CO₂?

(a) Acetic acid

(b) Ethylamine

(d) Ethyl alcohol

Answer. (a)

537. Which of the following reagents will convert acetic acid into acetyl chloride?

(a) NaCl

(b) HCl/ZnCl₂

(d) HCl

Answer. (c)

538. Butyric acid reacts with PCl₅ to give

(a) Benzoyl chloride

(b) 1-Chlorobutane

(d) 1-Chloropropane

Answer. (c)

539. Acetic acid undergoes reduction with LiAlH₄ to give

(a) Ethanol

(b) Ethane

(d) Ethyne

Answer. (a)

540. Acetic acid reacts with methyl alcohol in the presence of an acid catalyst to give

(a) Methyl formate

(b) Ethyl formate

(d) Ethyl acetate

Answer. (c)

541. Calcium acetate on strong heating gives

(a) Methane + CaCO₃

(b) Ethane + CaCO₃

(d) Ethane + CaO

Answer. (c)

542. CH₃(CH₂)₄ is the sodium salt of hexanoic acid. The water solubility of this salt is :

(a) higher than that of hexanoic acid

(b) lower than that of hexanoic acid

(d) not predictable

Answer. (a)

543. Which of the following compounds has the lowest boiling point?

(a) 1-butanol

(b) butanoic acid

(d) methyl propanoate

Answer. (c)

544. Which of the following is the correct ranking in decreasing order of relative Boiling Point of carbonyl containing compounds?

(a) primary amide > carboxylic acid >> ester ~ acyl chloride ~ aldehyde ~ ketone

(b) ester > carboxylic acid >> amide ~ acyl chloride ~ aldehyde ~ ketone

(d) carboxylic acid > amide >> ester ~ acyl chloride ~ aldehyde ~ ketone

Answer. (a)

545. Acetyl chloride undergoes nucleophilic substitution at a faster rate than methyl acetate because .

(a) the ester is more sterically hindered than the acid chloride

(b) the acid chloride is more sterically hindered than the ester

(d) chloride is a better leaving group than methoxide

Answer. (d)

546. Esters and amides are most easily made by nucleophilic acyl substitution reactions on :

(a) acid anhydrides

(b) carboxylates

(d) acid chlorides

Answer. (d)

547. Which of the following conditions will drive the equilibrium of the Fischer esterification towards ester formation?

(a) addition of water

(b) removal of water as it is formed

(d) both (b) and (c)

Answer. (d)

548. Which of the following statements describes the first step in the mechanism of the aldol condensation?

(a) An alpha hydrogen is abstracted by the base to form an enolate anion.

(b) A nucleophilic base attacks the carbonyl carbon atom.

(d) The alpha hydrogen is abstracted by an acid to the enolate anion.

Answer. (a)

549. Ammonium acetate on strong heating gives

(a) Urea

(b) Formamide

(d) Acetamide

Answer. (d)

550. Which reaction does not yield an ester as one of the products?

(a) A carboxylic acid is heated with an alcohol

(b) A Grignard reagent is added to a carboxylic acid

(d) An alkyl halide is heated with the salt of a carboxylic acid

Answer. (b)

551. Silver acetate reacts with Br₂ to form methyl bromide, carbon dioxide, and AgBr. This is an example of

(a) Wurtz reaction

(b) Etard's reaction

(d) Perkin reaction

Answer. (c)

552. Hunsdiecker reaction is used for the preparation of

(a) Alkyl chlorides and bromides

(b) Alkyl nitrates and nitrites

(d) Alcohols

Answer. (a)

553. A compound undergoes reduction with LiAlH4. It also dissolves in aqueous NaOH from which it can be recovered by addition of HCl. The compound is

(a) a carboxylic acid

(b) an ester

(d) an alcohol

Answer. (a)

554. Acid chlorides undergo reduction to the corresponding aldehydes on treatment with hydrogen in the presence of Pd/BaSO4. This reaction is called :

(a) Clemmensen reduction

(b) Rosenmund reduction

(d) None of these

Answer. (b)

555. Acetic anhydride is obtained by the reaction of :

(a) Acetic acid and sodium

(b) Acetic acid and water

(d) Acetic acid and P₂O₅

Answer. (d)

556. Acetic anhydride reacts with ethanal to give

(a) Methyl acetate

(b) Methyl propanoate

(d) Ethyl propanoate

Answer. (c)

557. Acetamide on heating with P₂O₅ gives :

(a) Methylamine

(b) Ethylamine

(d) None of these

Answer. (c)

558. Acetamide is a much weaker base than ammonia. This is because

(a) the electron withdrawing effect of the C=O group makes the lone pair of electrons on nitrogen atom less available for protonation.

(b) ) the electron withdrawing effect of the C=O group makes the lone pair of electrons on nitrogen atom more available for protonation.

(d) an H atom from the nitrogen is less easily lost from CH₃CONH₂ than from NH₃.

Answer. (a)

559. Which of the following statements is False about acetamide?

(a) reacts with Br₂/NaOH to form tertiary amine

(b) undergoes acid-hydrolysis to form acetic acid

(d) is a white crystalline solid, soluble in water

Answer. (a)

560. The C—C—O bond angle in is approximately

(a) 60°

(b) 109.5°

(d) 120°

Answer. (d)

561. Consider a small aliphatic 1° amine, 1° alcohol, ester, carboxylic acid, and amide, all of similar molecular weight. Which one is most likely to have the

highest boiling point?

(a) The amide

(b) The alcohol

(d) The carboxylic acid

Answer. (a). Amides can form very strong H-bonds because of ability of the N to donate electrons to the carbonyl (more so than OH of a carboxylic acid) and give the O considerable negative charge, thereby enhancing the H-bond acceptor capability of the molecule. Considering compounds of similar molecular weight and carbon chain structure, the general trend is (highest to lowest boiling point) : amides, carboxylic acids, alcohols, amines, aldehydes/ketones/esters, alkynes, alkenes, and alkanes.

562. Which of the following acid-derivatives are most stable?

(a) Acid chlorides

(b) Esters

(d) Anhydrides

Answer. (c). Amides are the most stable of the carboxylic acid derivatives because they have the most stable resonance forms :

563. Which of the following will have the highest boiling point?

(a) Diethyl ether

(b) n-Butane

(d) n-Propylamine

Answer. (c)

564. Acetamide can be converted into methylamine by

(a) P₂O₅

(b) Br₂/NaOH

(d) LiAlH₄

Answer. (b)

565. Acetamide on reduction with LiAlH4 gives

(a) Acetaldehyde

(b) Ethylamine

(d) Methylamine

Answer. (b)

566. Amides undergo hydrolysis under acidic conditions to give

(a) Carboxylic acid and amine

(b) Carboxylic acid and ammonium ion

(d) Carboxylate ion and amine

Answer. (b)

567. By which of the following methods can CH₃CONH₂ be converted to CH₃CN?

(a) Oxidize with Na₂Cr₂O₇/H+

(b) Heat with concentrated sulfuric acid

(d) Warm with P2O5

Answer. (d)

568. Which of the following reagents will react with acetamide to form methylamine?

(a) LiAlH₄

(b) Br₂/NaOH

(d) H₂/Ni

Answer. (b)

569. Which of the following compounds does not form a salt with dilute HCl?

(a) CH₃CH₂CONH₂

(b) (CH₃CH₂)₂NH

(d) (CH₃CH₂)₃N

Answer. (a)

570. Propionamide on heating with a mixture of bromine and sodium hydroxide gives

(a) Propane

(b) Propylamine

(d) Ethylamine

Answer. (d)

571. What happens when urea is treated with hydrazine?

(a) Biuret is formed

(b) Semicarbazide is formed

(d) Acetamide is formed

Answer. (b)

572. Carbonyl chloride reacts with ammonia to give

(a) Urea

(b) Acetone

(d) Chloroform

Answer. (a)

573. Which of the following is not a constituent of normal urine?

(a) Albumin

(b) Urea

(d) Uric acid

Answer. (a)

574. Esters can be formed by nucleophilic substitution reactions of :

(a) carboxylic acids and alcohols ; acid-catalyzed

(b) acid chlorides and alcohols

(d) neither of the above

Answer. (c)

575. The conversion is called :

(a) Oxidation

(b) Dehydration

(d) Hydrolysis

Answer. (c)

576.

The following reaction is called :

(a) Saponification

(b) Condensation

(d) Esterification

Answer. (a)

577. Hydrolysis of an ester can be accomplished by :

(a) base-promoted hydrolysis

(b) acid-catalyzed hydrolysis

(d) neither of the above

Answer. (c)

578. Basic-hydrolysis of esters is called

(a) Acetylation

(b) Acidification

(d) Saponification

Answer. (d)

579. Base-catalyzed condensation of two ester molecules to form an alcohol and β-keto ester is called

(a) Claisen condensation

(b) Corey-House reaction

(d) Transesterification

Answer. (a)

580. Ethyl acetoacetate undergoes acid-hydrolysis with dilute HCl to form

(a) Acetoacetic acid

(b) Succinic acid

(d) Adipic acid

Answer. (a)

581. The ethyl derivative of acetoacetic ester on basic-hydrolysis gives

(a) Acetic acid

(b) Acetic acid and propionic acid

(d) Acetic acid and n-butyric acid

Answer. (a)

582. Ethyl acetate on heating with sodium ethoxide gives

(a) Ethyl acetoacetate

(b) Sodium acetate

(d) Diethyl ether

Answer. (a)

583. When ethyl acetoacetate is subjected to ketonic hydrolysis, the ketone

obtained is

(a) Dimethyl ketone

(b) Methyl ethyl ketone

(d) Methyl n-propyl ketone

Answer. (c)

584. Ethyl acetoacetate reacts with phenylhydrazine to give

(a) Antipyrine

(b) Aspirin

(d) DDT

Answer. (a)

585. Keto-enol tautomerism is shown by

(a) Benzaldehyde

(b) Acetone

(d) Acetic acid

Answer. (b)

586. Fatty acids are

(a) Unsaturated dicarboxylic acids

(b) Long-chain alkanoic acids

(d) Aromatic dicarboxylic acids

Answer. (b)

587. Sodium or potassium salts of fatty acids are called

(a) Proteins

(b) Terpenes

(d) Soaps

Answer. (d)

588. Soap is

(a) a mixture of salts of fatty acids

(b) a salt of glycerol

(d) a mixture of aromatic ethers

Answer. (a)

589. A wax is

(a) a nonpolar solid

(b) a long-chain alcohol

(d) none of these

Answer. (a)

590. Fats and oils are

(a) monoesters of glycerol

(b) diesters of glycerol

(d) diesters of glycol

Answer. (c). Fats are solid triesters of glycerol. Oils are liquid triesters of glycerol.

591. Fats differ from waxes in that fats have :

(a) More unsaturation

(b) Higher melting points

(d) Longer fatty acids

Answer. (c)

592. Oleic acid is a fatty acid containing

(a) 12 carbons

(b) 14 carbons

(d) 18 carbons

Answer. (d)

593. Both stearic acid and linoleic acid have 18 carbons. Linoleic acid is unsaturated, while stearic acid is saturated. The melting point of stearic acid :

(a) is higher than linoleic acid

(b) is lower than linoleic acid

(d) can not predict, insufficient information

Answer. (a)

594. Liquid oils can be converted to solid fats by

(a) Hydrogenation

(b) Saponification

(d) Oxidation of double bonds

Answer. (a)

595. Partial hydrogenation of vegetable oils in the presence of Ni catalyst at 200°C gives

(a) Vanaspati ghee

(b) Margarine

(d) None of these

Answer. (a)

596. Alkaline hydrolysis of oils (or fats) is called :

(a) Saponification

(b) Fermentation

(d) Rancidification

Answer. (a)

597. Saponification of a fat

(a) always results in the formation of insoluble soaps

(b) produces glycerol and soap

(d) is used in the production of lactic acid

Answer. (b)

598. Which of the following compounds will not be classified as lipids?

(a) Fats

(b) Waxes

(d) Oils

Answer. (b)

599. Synthetic detergents can be represented by the following general formula

(a) RONa

(b) ROSO₃Na

(d) RCOOH

Answer. (b)

600. The degree of unsaturation of a fat can be determined by means of its

(a) Iodine number

(b) Octane number

(d) Melting point

Answer. (a)

601. Which of the following statements is not true about fatty acids?

(a) Fatty acids are carboxylic acids with long hydrocarbon side chains.

(b) The double bonds in unsaturated fatty acids are always conjugated.

(d) Fatty acids can be saturated or unsaturated.

Answer. (b)

602. Which of the following best explains why the melting points of saturated fats increase with increasing molecular weight?

(a) decreased hydrogen bonding

(b) increased hydrogen bonding

(d) increased intermolecular van der Waal’s interactions

Answer. (d)

603. Which of the following terms best describes the compound below?

CH₃(CH₂)₁₂CO₂H

(a) a fatty acid

(b) an oil

(d) a soap

Answer. (a)

604. Which of the following terms best describes the compound below?

CH₃(CH₂)₇CH=CH(CH₂)₇CO₂H

(a) an unsaturated fatty acid

(b) a triglyceride

(d) a micelle

Answer. (a)

605. Which of the following statements best describes the structure of waxes?

(a) long-chain unsaturated carboxylic acids

(b) long-chain saturated carboxylic acids

(d) short-chain esters

Answer. (c)

606. Which of the following terms best describes the compound below?

CH₃(CH₂)₂₆CO₂CH₂(CH2)₃₂CH₃

(a) a fat

(b) a wax

(d) an unsaturated triglyceride

Answer. (b)

607. Which of the following statements is not true about triacylglycerols?

(a) When solids and semisolids at room temperature, they are called fats.

(b) When liquids at room temperature, they are called oils.

(d) Triacylglycerols with low melting points are composed of saturated fatty acids, causing them to be liquids at room temperature.

Answer. (d)

608. Triglycerides which are solids or semisolids at room temperature are called

(a) oil

(b) fat

(d) cholesterol

Answer. (b)

609. Which of the following statements is not true about phospholipids?

(a) They are similar to triacylglycerols except that the middle OH group of glycerol reacts with a phosphate rather than with a fatty acid.

(b) They constitute a major component of cell membranes.

(d) The C-2 carbon of glycerol in phosphoacylglycerols has the R configuration.

Answer. (a)

610. The compound methylamine, H₃C–NH₂, contains a C–N bond. In this bond, which of the following best describes the charge on the nitrogen atom?

(a) slightly positive

(b) uncharged

(d) –1

Answer. (c)

611. Triethylamine [(CH₃CH₂)₃N] is a molecule in which the nitrogen atom is

hybridized and the CNC bond angle is .

(a) sp2; >109.5°

(b) sp2; <109.5°

(d) sp3; <109.5°

Answer. (d)

612. The N–H bond in the ammonium ion, NH₄+, is formed by the overlap of what two orbitals?

(a) sp3–sp3

(b) sp3–sp2

(d) sp3–s

Answer. (d)

613. What is the hybridization of the nitrogen atom in CH₃NH₂?

(a) sp

(b) sp2

(d) s-sp3

Answer. (c)

614. What is the hybridization of the carbon atom in CH₃NH₂?

(a) 3sp3

(b) sp

(d) sp3

Answer. (d)

615. What type of intermolecular interactions does (CH₃CH₂)₂NH undergo?

(a) induced dipole-induced dipole

(b) dipole-dipole

(d) all of these

Answer. (d)

616. Assuming roughly equivalent molecular weights, which of the following would have the highest boiling point?

(a) a tertiary amine

(b) a quaternary ammonium salt

(d) an ether

Answer. (b)

617. Which of the following statements is false about primary amines?

(a) They can be prepared by reduction of nitriles with LiAlH4.

(b) They do not form salts with acids.

(d) They are basic and soluble in water.

Answer. (b)

618. Which of the following statements is false about secondary amines?

(a) They react with chloroform and NaOH to form isocyanides.

(b) They can be prepared by reduction of isocyanides.

(d) They react with ice-cold nitrous acid to give nitrosamine (yellow oil).

Answer. (a)

619. The hybridization of nitrogen in an amine is

(a) sp

(b) sp3

(d) sp4

Answer. (b)

620. Which of the following compounds is a secondary amine? (a)

(b) H₂NCH₂CH₂NH₂

(d) (CH₃)₃N

Answer. (c)

621. A sample of pure amine molecules is found to possess no intermolecular H- bonding. This sample is most likely :

(a) 1° amine

(b) 2° amine

(d) all of these

Answer. (c)

622. Which of the following is least soluble in water?

(a) Methylamine

(b) Trimethylamine

(d) Aniline

Answer. (d)

623. Which of the following is most soluble in water?

(a) CH₃CH₂CH₃

(b)

(d) CH₃CH₂CH₂NH₂

Answer. (d)

624. Which amine is NOT soluble in water?

(a) Methylamine

(b) Dimethylamine

(d) All are water-soluble

Answer. (d). Amines from H-bonds with water. Therefore, all low-molecular weight amines are soluble in water.

625. Consider a 1°, 2° and 3° amine, all of equivalent molecular weight. Which amine is most likely to have the lowest boiling point?

(a) 1° amine

(b) 2° amine

(d) Not enough information to determine

Answer. (c). The 3° amines do not form hydrogen bonds to one another. The 1° and 2° amines can form hydrogen bonds to themselves and therefore have higher boiling points than 3° amines.

626. Which of the following will have the highest boiling point?

(a) Methylamine

(b) Diethylamine

(d) Triethylamine

Answer. (d)

627. Which compound has the highest boiling point?

1. CH₃CH₂CH₃ 2. CH₃CH₂OH 3. CH₃CH₂NH₂

(a) 1

(b) 2

(d) 2 and 3 have similar boiling points

Answer. (b). Amines are fairly polar, but they boil at temperatures lower than those of alcohols of similar chain length and structure. Amines do have higher boiling points than alkanes because they possess H-bond donors and acceptors.

628. Which of the following has the highest boiling point?

(a) CH₃CH₂CH₂CH₃

(b) CH₃CH₂CH₂CH₂Cl

(d) CH₃CH₂CH₂CH₂F

Answer. (c)

629. Amines are generally classified as

(a) Weak acids

(b) Strong acids

(d) Strong bases

Answer. (c)

630. Acetamide reacts with Br₂/NaOH to give

(a) Methylamine

(b) Urea

(d) Acetyl bromide

Answer. (a)

631. Acetonitrile undergoes reduction with LiAlH4 to form :

(a) Methylamine

(b) Dimethylamine

(d) Trimethylamine

Answer. (c)

632. Reduction of an imine will give an

(a) Acid

(b) Amide

(d) Alcohol

Answer. (c)

633. Which of the following is most basic?

(a) Ammonia

(b) Methylamine

(d) Trimethylamine

Answer. (c)

634. Alkyl halides react with ammonia in the presence of base to form :

(a) primary amines

(b) nitrated alkyl halides

(d) quaternary ammonium salts

Answer. (a)

635.

The major product of the following reaction is :

(a) 1° amine

(b) 2° amine

(d) amide

Answer. (c)

636. Aliphatic primary amines react with cold nitrous acid to form

(a) Alcohols

(b) Diazonium salts

(d) Nitroalkanes

Answer. (a)

637. Which type of amine produces N₂ when treated with HONO?

(a) Primary

(b) Secondary

(d) Quaternary

Answer. (a)

638. Methylamine reacts with nitrous acid to form

(a) CH₃CH₃

(b) CH₃OH

(d) CH₃CH₂OH

Answer. (b)

639. Which of the following compounds react with nitrous acid to form an alcohol?

(a) CH₃CH₂NH₂

(b) (CH₃CH₂)₂NH

(d)

Answer. (b)

640. A nitrile can be made by dehydrating an amide. However, for this reaction to occur, the amide must be :

(a) primary

(b) secondary

(d) N-methylated

Answer. (a)

641. Which of the following amines react with nitrous acid to form nitrosoamine?

(a) Ethylamine

(b) Triethylamine

(d) Isopropylamine

Answer. (c)

642. Which of the following does not react with acyl chlorides to form amides :

(a) ammonia

(b) 1° amine

(d) 3° amine

Answer. (d)

643. Hinsberg's reagent is

(a) Pd + BaSO₄

(b) p-Toluenesulfonic acid

(d) Benzenesulfonic acid

Answer. (d)

644. Which of the following compounds will dissolve in aqueous NaOH after undergoing reaction with Hinsberg reagent?

(a) CH₃CH₂NH₂

(b) (CH₃CH₂)₂NH

(d) (CH₃)₃N

Answer. (a)

645. Which of the following compounds does not react with acetyl chloride?

(a) Methylamine

(b) Dimethylamine

(d) Trimethylamine

Answer. (d)

646. A primary amine can be identified by using

(a) HCl

(b) CHCl₃

(d) CHCl₃ + KOH

Answer. (d)

647. Carbylamine test is given by

(a) Primary amines

(b) Secondary amines

(d) None of these

Answer. (a)

648. Which of the following describes the side chain for Alanine?

(a) hydrogen

(b) ethyl group

(d) isopropyl group

Answer. (c)

649. Which of the following describes the side chain for Valine?

(a) ethyl group

(b) hydrogen

(d) isopropyl group

Answer. (d)

650. Which of the following describes the side chain of Leucine?

(a) ethyl group

(b) isopropyl group

(d) isobutyl group

Answer. (d)

651. Which of the following amino acids has an aliphatic R group?

(a) Serine

(b) Cysteine

(d) Leucine

Answer. (d)

652. Which of the following amino acids has an aromatic R group?

(a) Serine

(b) Cysteine

(d) Tyrosine

Answer. (d)

653. Which of the following amino acids has a sulfur in the R group?

(a) Serine

(b) Cysteine

(d) Tyrosine

Answer. (d)

654. Which of the following amino acids has a heterocyclic R group?

(a) Glycine

(b) Threonine

(d) Aspartic acid

Answer. (c)

655. The α-carbon of all the amino acids is a chirality center except for

(a) Glycine

(b) Threonine

(d) Aspartic acid

Answer. (a)

656. Which of the following is correct for an amino acid solution when it is in the acidic form?

(a) pH > pK_a

(b) pH < pK_a

(d) pH = 7

Answer. (b)

657. When a disulfide linkage is formed, the compound containing this new linkage has been .

(a) hydrolyzed

(b) dehydrated

(d) oxidized

Answer. (d)

658. Which of the following structures can polypeptides have?

(a) primary structure

(b) secondary structure

(d) all of the these

Answer. (d)

659. Which of the following is the first step in the determination of the primary structure of proteins?

(a) determining the number and kind of amino acids in the peptide

(b) reducing the disulfide bridges in the protein

(d) protecting the C-terminal of the peptide

Answer. (b)

660. What are enzymes?

(a) saccharides that catalyze chemical reactions

(b) unsaturated fats that catalyze chemical reactions

(d) proteins that catalyze chemical reactions

Answer. (d)

661. Which of the following may characterize the “secondary structure” of proteins?

(a) conformation of the protein backbone

(b) α-Helix

(d) all of the above

Answer. (d)

662. Which of the following is the “quaternary structure” of proteins concerned with?

(a) sequence of amino acids in the peptide chain

(b) description of the way the peptide chains are arranged with respect to each other

(d) conformation of the protein backbone

Answer. (b)

663. Which of the following protein structures does “denaturation” destroy?

(a) primary and secondary structures

(b) secondary and tertiary structures

(d) secondary, tertiary, and quaternary structures

Answer. (d)

664. Which of the following are capable of denaturing proteins?

(a) organic solvents

(b) extreme pH

(d) all of the these

Answer. (d)

665. The monomeric units that make up peptides and protein polymers are

(a) nucleic acids

(b) amino acids

(d) amylopectins

Answer. (b)

666. A zwitterion is

(a) an ion that is positively charged in solution

(b) an ion that is negatively charged in solution

(d) a carbohydrate with an electrical charge.

Answer. (c)

667. A zwitterion has which of the following properties

(a) no net charge

(b) a high melting point

(d) all of these

Answer. (d)

668. An aqueous solution of glycine is neutral because of the formation of :

(a) Carbanion

(b) Zwitterion

(d) Free radicals

Answer. (b)

669. Which one of the following compounds form zwitterions?

(a) carbonyl compounds

(b) amino acids

(d) heterocyclic compounds

Answer. (b)

670. The pH at which the amino acid shows no tendency to migrate when placed in an electric field is known as its :

(a) Isoelectric point

(b) Dipole moment

(d) Wavelength

Answer. (a)

671. The isoelectric point of a protein is

(a) the pH at which the protein molecule has no charges on its surface.

(b) the pH at which a protein in solution has an equal number of positive and negative charges.

(b) None of these.

Answer. (b)

672. Which of the following reactions is suitable for the preparation of α-amino acids?

(a) Schmidt reaction

(b) Hofmann's degradation of amides

(b) Reduction of nitro compounds

Answer. (c)

673. Glycine is

(a) NH₂CH₂COOH

(b) NH₂CH₂CH₂CH₂CH₂NH₂

(b) BrCH₂COOH

Answer. (a)

674. Glycine reacts with nitrous acid to form :

(a) Glycollic acid

(b) Diketopiperazine

(d) Ethyl alcohol

Answer. (a)

675. When glycine is heated, it forms

(a) Diketopiperazine

(b) Acrylic acid

(d) Butyrlactam

Answer. (a)

676. Glycine is a unique amino acid because it

(a) has no chiral carbon

(b) has a sulfur containing R group

(d) is an essential amino acid

Answer. (a)

677. Which of the following organic ions results when glycine is treated with concentrated HCl?

(a)

(b)

(c)

(d) Answer. (a) 678. Proteins are

(a) polyamides

(b) Polymers of ethylene

(d) Polymers of propylene

Answer. (a)

679. The five elements present in most naturally occurring proteins are :

(a) C, H, O, P, and S

(b) N, C, H, O, and I

(d) C, H, O, S, and I

Answer. (c)

680. The nitrogen content of proteins can be quantitatively determined by

(a) Carius method

(b) Kjeldahl's method

(d) Rast method

Answer. (b)

681. Which of the following is the main structural feature of proteins?

(a) Peptide linkage

(b) Ester linkage

(d) α,β-Linkage

Answer. (a)

682. The linear arrangement of amino acid units in proteins is called :

(a) primary structure

(b) secondary structure

(d) quaternary structure

Answer. (a)

683. The primary structure of a protein refers to :

(a) whether the protein is fibrous or globular

(b) the amino acid sequence in the polypeptide chain

(d) the presence or absence of an α-helix.

Answer. (b)

684. The α-Helix is a common form of

(a) Primary structure

(b) Tertiary structure

(d) None of these

Answer. (c)

685. The α-Helix is held in a coiled conformation partially because of :

(a) Optical activity

(b) Hydrogen bonding

(d) Delocalization

Answer. (b)

686. The double helical structure of DNA is held together by

(a) sulfur-sulfur linkages

(b) peptide bonding

(d) glycosidic bonds

Answer. (c)

687. Upon hydrolysis, proteins give

(a) Amino acids

(b) Hydroxy acids

(d) Alcohols

Answer. (a)

688. Complete hydrolysis of proteins produces :

(a) Ammonia and carbon dioxide

(b) Urea and uric acid

(d) Glycogen and a fatty acid

Answer. (c)

689. Digestion of proteins involves

(a) changes in secondary structure only

(b) cleavage of peptide linkages

(d) removal of all NH2 groups in the form of NH3

Answer. (b)

690. Irreversible precipitation of proteins caused by heating is called :

(a) Polymerisation

(b) Denaturation

(d) Inversion

Answer. (b)

691. Precipitation or coagulation of proteins may be caused by

(a) Heat

(b) Changes in pH

(d) All of these

Answer. (d)

692. Ninhydrin test is given by

(a) Carbohydrates

(b) Proteins

(d) Alkenes

Answer. (b)

693. Which of the following tests is not used for testing proteins?

(a) Ninhydrin test

(b) Biuret test

(d) Tollens' test

Answer. (d)

694. A protein solution on warming with concentrated HNO₃ may turn yellow. This test is called :

(a) Xanthoproteic test

(b) Ninhydrin test

(d) Million's test

Answer. (a)

695. A compound gives a positive Tollens' test but negative Ninhydrin test. It is

(a) a protein

(b) an amino acid

(d) pyridine

Answer. (c)

696. Cycloalkanes have the same molecular formula as :

(a) Alkanes

(b) Alkenes

(d) Cycloalkenes

Answer. (b)

697. Which of the following compounds will give cyclopropane on treatment with sodium in dry ether?

(a) 1,3-Dibromopropane

(b) 1,1-Dibromopropane

(d) 2,2-Dibromopropane

Answer. (a)

698. Which of the following cycloalkanes is most reactive?

(a) Cyclopropane

(b) Cyclohexane

(d) Cycloheptane

Answer. (a)

699. Which of the following compounds will react most readily with concentrated sulfuric acid?

(a) Ethane

(b) Cyclohexane

(d) Cyclohexene

Answer. (d)

700. A compound of formula C6H12 does not react with concentrated sulfuric acid.

The compound could be

(a) Alkane

(b) Cycloalkane

(d) Cycloalkene

Answer. (b)

701. Which of the following molecules will decolorize bromine in carbon tetrachloride most readily?

(a) 1,2-Dimethylcyclopropane

(b) Cyclopentane

(d) Cyclohexane

Answer. (a)

702. Cyclopropane reacts with concentrated HBr to give.

(a) 1-Bromopropane

(b) Bromocyclopropane

(d) 1,2-Dibromopropane

Answer. (a)

703. Cyclobutane reacts with hydrogen in the presence of nickel catalyst at 200°C to give

(a) Butane

(b) 1-Butene

(d) None of these

Answer. (a)

704. Cyclohexanol can be converted into cyclohexene by heating with

(a) Zn(Hg) and HCl

(b) Concentrated H₂SO₄

(d) H₂ and Ni

Answer. (b)

705. The bond angle between carbon atoms in cyclohexane is

(a) 109°28'

(b) 60°

(d) 120°

Answer. (a)

706. Which of the cycloalkanes is not expected to have ring strain?

(a) Cyclopropane

(b) Cyclobutane

(d) None of these

Answer. (c)

707. The bond angle between carbon atoms in cyclohexane is

(a) 60°

(b) 90°

(d) 120°

Answer. (c)

708. Which of the following statements is false about cyclohexane?

(a) It is a saturated cyclic hydrocarbon

(b) All C–C–C bond angles are 109°28'

(d) It can exist in two conformations which are designated as the boat-form and the chair-form.

Answer. (c)

709. The most stable conformation of cyclohexane is the :

(a) Haworth form

(b) Boat form

(d) Chair form

Answer. (d)

710. What percentage of cyclohexane molecule is estimated to be in the boat form at any given time?

(a) over 99%

(b) between 90% and 99%

(d) less than 1% Answer. (d) 711. Uriedes are

(a) Halogen derivatives of urea

(b) Acetyl derivatives of urea

(d) None of these

Answer. (b)

712. Uric acid on oxidation with alkaline KMnO4 forms :

(a) Urea

(b) Barbituric acid

(d) Caffeine

Answer. (c)

713. Diethyl malonate reacts with urea in the presence of sodium ethoxide to form

(a) Uric acid

(b) Barbituric acid

(d) Barbital

Answer. (b)

714. A carbohydrate composed of three to ten sugar molecules is called a(n) :

(a) disaccharide

(b) oligosaccharide

(d) monosaccharide

Answer. (b)

715. All chiral D-sugars rotate plane-polarized light :

(a) clockwise

(b) counterclockwise

(d) in a direction that cannot be predicted but must be determined experimentally

Answer. (d)

716. How many chirality centers are there in a 2-ketohexose?

(a) 2

(b) 3

(d) 5

Answer. (b)

717. How many stereoisomers are possible for a 2-ketohexose?

(a) 2

(b) 4

(d) 16

Answer. (c)

718. Which of the following statements best describes the difference between amylose and amylopectin?

(a) Amylose is a branched polysaccharide while amylopectin is a chain polysaccharide.

(b) Amylose is a straight-chain polysaccharide while amylopectin is a branched polysaccharide.

(d) Amylose is composed of thousands of D-glucose units while amylopectin is composed of thousands of D-galactose units.

Answer. (b)

720. An aqueous solution of glucose behaves as an aldehyde because

(a) it is hydrolyzed by water to the free aldehyde

(b) it is a ketone, but is in equilibrium with the aldehyde form

(d) its cyclic hemiacetal, the predominant form, is in equilibrium with the free aldehyde form

Answer. (d)

720. Which of the following statements best describes the meaning of “mutarotation”?

(a) a rapid exchange between the α and β forms of diastereomeric sugars

(b) a rapid exchange between the D and L forms

(d) a slow change in optical rotation to reach an equilibrium value

Answer. (d)

721. In solution, glucose exists as .

(a) the open-chain form only

(b) the cyclic hemiacetal form only

(d) an equilibrium mixture of the open-chain form and cyclic hemiacetal forms

Answer. (d)

722. Anomers of D-glucopyranose differ in their stereochemistry at .

(a) C1 (b) C2 (c) C3 (d) C4

Answer. (a)

723. Which of the following statements best describes the meaning of a “glycoside”?

(a) It is the mirror image of a sugar.

(b) It is the hemiacetal of a sugar.

(d) It is the enantiomer of a sugar.

Answer. (c)

724. Which of the following would give a positive Tollen’s test?

(a) α-D-glucopyranose

(b) methyl β-D-glucopyranoside

(d) methyl α-D-ribofuranoside

Answer. (a)

725. Which of the following is true about sucrose?

(a) It hydrolyzes to fructose and glucose.

(b) It is a reducing sugar.

(d) It undergoes mutarotation in water.

Answer. (a)

726. Which term describes a sugar where one of the OH groups has been replaced with a hydrogen?

(a) amino sugar

(b) imino sugar

(d) deoxy sugar

Answer. (d)

727. Monosaccharides are classified according to :

(a) the number of carbon atoms in the molecule.

(b) whether they contain an aldehyde or a ketone group.

(d) all of the above.

Answer. (d)

728. Which is a monosaccharide?

(a) Sucrose

(b) Maltose

(d) Cellulose

Answer. (c)

729. Which is a disaccharide?

(a) Glucose

(b) Maltose

(d) Cellulose

Answer. (b)

730. Which of the following is not a monosaccharide?

(a) Ribose

(b) Fructose

(d) Glucose

Answer. (c)

731. The designation D or L before the name of a monosaccharide

(a) indicates the direction of rotation of polarized light.

(b) indicates the length of the carbon chain in the carbohydrate.

(d) indicates the position of the asymmetric carbon atoms in the carbohydrate.

Answer. (c)

732. The principal sugar in blood is

(a) Fructose

(b) Glucose

(d) Galactose

Answer. (b)

733. Glucose cannot be classified as

(a) a hexose

(b) an oligosaccharide

(d) a monosaccharide

Answer. (b)

734. Which of the following statements is false about glucose?

(a) it is a reducing sugar.

(b) it is a disaccharide.

(d) it is a polyalcohol.

Answer. (b)

735. Which of the following statements is false about α-D-glucose?

(a) it has a pyranose ring.

(b) it is a hemiacetal.

(d) it is the purest form of table sugar.

Answer. (d)

736. α-D-Glucose is different from β-D-glucose

(a) in the configuration at C-1

(b) because they are mirror images of each other

(d) because they are geometrical isomers

Answer. (a)

737. α-D-Glucopyranose is a(n) :

(a) hemiacetal

(b) hemiketal

(d) ketal

Answer. (a)

738. The number of asymmetric carbon atoms in the α-D-glucopyranose molecule is :

(a) 2

(b) 3

(d) 5

Answer. (d)

739. Which of the following statements is false about an aldohexose?

(a) It is a monosaccharide.

(b) It contains a potential aldehyde group.

(d) Fructose is an aldohexose.

Answer. (d)

740. All of the following monosaccharides give the same osazone except

(a) Galactose

(b) Glucose

(d) Mannose

Answer. (a)

741. Mutarotation is a term related to

(a) Interconversion of anomers

(b) Relationship of D- and L- families

(d) Number of monsaccharides in a carbohydrate

Answer. (a)

742. The mutarotation of glucose is characterized by :

(a) a change from an aldehyde to ketone structure.

(b) a change of specific rotation from a (+) to a (–) value.

(d) the irreversible change from α-D to the β-D form.

Answer. (c)

743. Which of the following statements is false about glyceraldehyde?

(a) Its IUPAC name is 1,2-dihydroxypropanal

(b) It is isomeric with 1,3-dihydroxypropanone

(d) It shows mutarotation

Answer. (d)

744. Common table sugar is

(a) Glucose

(b) Sucrose

(d) Maltose

Answer. (b)

745. Which of the following carbohydrates is sweeter than sucrose?

(a) Glucose

(b) Fructose

(d) None of these

Answer. (b)

746. By approximately what factor is the sweetness of saccharin greater than that of sugar?

(a) 5

(b) 50

(d) 1000

Answer. (c)

747. Which of the following statements is false about sucrose?

(a) It is also called table sugar.

(b) It may be fermented by yeast to produce alcohol.

(d) It does not reduce Tollens' reagent.

Answer. (c)

748. The sugar that yields only glucose on hydrolysis is

(a) Lactose

(b) Sucrose

(d) Fructose

Answer. (c)

749. A reducing sugar will

(a) react with Fehling's test

(b) not react with Fehling's test

(d) always be a ketone

Answer. (a)

750. Which of the following carbohydrates is not a reducing sugar?

(a) Glucose

(b) Sucrose

(d) Lactose

Answer. (b)

751. Which of the following carbohydrates will not give a red precipitate of Cu₂O when heated with Benedict's solution?

(a) Maltose

(b) Glucose

(d) Fructose

Answer. (c)

752. Which of the following compounds reduces Tollens' reagent?

(a) Glucose

(b) Sucrose

(d) Acetic acid

Answer. (a)

753. The reagent that can be used to differentiate an aldose and a ketose is :

(a) Bromine water

(b) Fehling's solution

(d) None of these

Answer. (a)

754. Starch

(a) is a trisaccharide.

(b) is also called amylose.

(d) is a mixture of amylose + amylopectin.

Answer. (d)

755. The monosaccharide obtained by hydrolysis of starch is :

(a) D-Glucose

(b) Maltose

(d) D-Ribose

Answer. (a)

756. Which of the following statements is false about cellulose?

(a) It is a polymer of glucose molecules joined in β-1,4 linkages.

(b) It is a major component of cotton.

(d) It is used in the manufacture of Rayon fibres

Answer. (c)

757. Which of the following products is not derived from cellulose?

(a) Rayon

(b) Insulin

(d) Paper

Answer. (b)

758. Coal-tar is the main source of :

(a) Aromatic compounds

(b) Aliphatic compounds

(d) None of these

Answer. (a)

759. Which of the following fractions of coal-tar distillation contains benzene?

(a) Light oil

(b) Middle oil

(d) Anthracene oil

Answer. (a)

760. Which of the following fractions of coal-tar distillation contains naphthalene?

(a) Light oil

(b) Middle oil

(d) Anthracene oil

Answer. (b)

761. What is the term used for isomers that are in rapid equilibrium?

(a) keto-enol tautomers

(b) constitutional isomers

(d) cis-trans isomers

Answer. (a)

762. Aromatic hydrocarbons are also called :

(a) Arenes

(b) Huckel's compounds

(d) Alkoxy compounds

Answer. (a)

763. Which of the following is an aromatic compound? (a)

(b)

(c)

(d)

Answer. (c)

764. Which of the following compounds is not an aromatic compound? (a)

(b)

(c)

(d)

Answer. (b)

765. Which of the following compounds is known as aniline? (a)

(b)

(c)

(d)

Answer. (c). (a) is Phenol, (b) is Toluene, and (d) is Benzoic acid. 766. Which of the following structures represent m-dichlorobenzene? (a)

(b)

(c)

(d)

Answer. (b)

767.

The best name for the following compound is :

(a) 3-Methyl-bromobenene

(b) 3-Bromoaniline

(d) 3-Bromotoluene

Answer. (d)

768. The correct IUPAC name for the following compound is :

(a) p-Nitrobenzene methanoic acid

(b) o-Nitrobenzoic acid

(d) m-Nitrobenzoic acid

Answer. (b)

769.

The correct IUPAC name for the following compound is :

(a) 2-Chloro-5-fluoro-1-hydroxybenzene

(b) 1-Hydroxy-2-chloro-5-fluorobenzene

(d) None of these

Answer. (d). The name should be 2-Chloro-5-fluorophenol.

770.

The correct IUPAC name for the following compound is :l

(a) 3-Bromo-4-ethyl-1-nitrobenzene

(b) 1-Ethyl-2-bromo-4-nitrobenzene

(d) 3-Bromo-1-ethyl-4-nitrobenzene

Answer. (d). The numbering is done to produce the smallest total. Therefore, number from the ethyl group toward the nitro group. List the substituents in alphabetic order.

771. Which of the following statements are correct concerning benzene?

(a) Benzene is a planar molecule.

(b) The six carbon-carbon bonds have the same length.

(d) (a) and (b)

Answer. (d)

772. Which of the following statements is incorrect about benzene?

(a) All of the carbon atoms are sp hybridized.

(b) It has delocalized electrons.

(d) All twelve atoms lie in the same plane.

Answer. (a)

773. Which of the following statements about benzene is correct?

(a) All of the carbon atoms are sp3 hybridized.

(b) It has no delocalized electrons.

(d) It is a planar molecule.

Answer. (d)

774. The delocalized π system in benzene is formed by a cyclic overlap of 6 orbitals.

(a) s

(b) p

(d) sp2

Answer. (b)

775. Aromatic molecules contain π electrons.

(a) no

(b) 4n + 2 (with n being an integer)

(d) 4n (with n an integer)

Answer. (b)

776.

Which of the structures below would be aromatic?

(a) I and IV

(b) I, III, and IV

(d) II

Answer. (c)

777. Which of the following is aromatic?

(a) cyclopentadienyl cation

(b) 1,3-cyclohexadiene

(d) cycloheptatrienyl cation

Answer. (d)

778. Which of the following is not a correct statement about the electrophilic substitution mechanism of benzene?

(a) Benzene functions as a nucleophile.

(b) Formation of a carbocation intermediate is the rate-determining step.

(d) The addition product is a frequently observed minor product.

Answer. (d)

779. What purpose does FeCl₃ serve in the electrophilic aromatic substitution reaction between chlorine and benzene?

(a) It serves as a radical initiator to produce the chlorine radical needed to propagate the chain reaction.

(b) It functions by destabilizing the carbocationic intermediate and thereby increases the rate of H+ loss.

(d) It serves as a Lewis acid catalyst by reacting with the Cl₂ and thereby activates it toward attack by benzene’s π electrons.

Answer. (d)

780. Which of the following is not a correct statement concerning the Friedel- Crafts acylation of benzene?

(a) An alkyl group substitutes for a hydrogen.

(b) The benzene ring attacks an acylium ion.

(d) The acylium ion is often produced from an acyl chloride.

Answer. (a)

781. What is the major organic product of the reaction between benzene and isobutyl chloride in the presence of AlCl3?

(a) tert-butylbenzene

(b) isobutylbenzene

(d) chlorobenzene

Answer. (a)

782. Which of the following statements are false about benzene?

(a) It is a planar molecule with bond angles 120°.

(b) It is immiscible with water forming the lower layer.

(d) It reacts with ethyl chloride in the presence of aluminium chloride to form ethylbenzene.

Answer. (b)

783. Which statement about the structure of benzene is not true?

(a) The two Kekule structures of benzene are in equilibrium.

(b) The carbon-carbon bond lengths in benzene are greater than the carbon-carbon double bonds in aliphatic compounds.

(d) The stability of benzene ring is much greater than the stability of 1,3,5- cycloheptatriene.

Answer. (a). Neither of the two Kekule structures for benzene has been isolated. No equilibrium exists between these two structures because they are resonance structures, differing only in the positions of electrons.

784. The carbon atoms in a benzene ring are :

(a) sp hybridized

(b) sp3 hybridized

(d) None of these

Answer. (c)

785. Which of the following compounds uses only sp2 hybridized carbons for bond formation?

(a)

(b)

(c)

(d)

Answer. (b)

786. The C–C bond length in benzene is

(a) greater than the C–C bond length in ethane.

(b) shorter than the C–C bond length in ethylene.

(d) intermediate between C–C bond length in ethane and C–C bond length in ethylene.

Answer. (d)

787. Which of the following compounds is aromatic? (a)

(b)

(c)

(d)

Answer. (b). Use the concept of aromaticity and Huckel rule to arrive at the correct answer.

788. Characteristic reactions of aromatic hydrocarbons are initiated by

(a) Electrophiles

(b) Nucleophiles

(d) Uncharged molecules

Answer. (a)

789. Phenol on distillation with Zinc dust gives

(a) Phenylzinc

(b) Benzene

(d) Benzoic acid

Answer. (b)

790. Which of the following statements is false about toluene?

(a) can be prepared by treating benzene with methyl chloride in the presence of AlCl₃.

(b) is converted to benzoic acid on refluxing with acidic KMnO₄ solution.

toluenesulfonic acid.

(d) can be nitrated with concentrated nitric acid to give a mixture of

ortho and meta nitrotoluene.

Answer. (d)

791. Which of the following reagents will react with methyl group rather than the

benzene ring in methylbenzene?

(a) Chlorine in the presence of uv light

(b) CH3Cl in the presence of AlCl₃

(d) Hydrogen in the presence of nickel

Answer. (a)

792. Which of the following can be made by the action of CH3Cl on benzene in the presence of aluminium chloride?

(a) Ethylbenzene

(b) o-Xylene

(d) m-Xylene

Answer. (b)

793. For reactions of ethylbenzene, the ethyl group is considered :

(a) ortho director

(b) ortho-para director

(d) ortho-meta director

Answer. (b)

794. Toluene reacts with bromine in the presence of uv light to give

(a) m-Bromotoluene

(b) Benzyl bromide

(d) Benzoyl bromide

Answer. (b)

795. Toluene reacts with chlorine in the presence of AlCl₃ to give

(a) o-Chlorotoluene

(b) o- plus p-Chlorotoluene

(d) o- plus m-Chlorotoluene

Answer. (b)

796. Toluene undergoes oxidation to give

(a) Benzyl alcohol

(b) Quinone

(d) Benzoic acid

Answer. (d)

797. Ethylbenzene undergoes oxidation with acidic potassium dichromate to give (a)

(b)

(c)

(d)

Answer. (d)

798. Oxidation of cumene with acidic K₂Cr₂O₇ gives

(a) Phenylacetic acid

(b) Benzaldehyde

(d) Benzoic acid

Answer. (d)

799. Oxidation of toluene with chromyl chloride gives benzaldehyde. This reaction is known as

(a) Perkin reaction

(b) Benzoin condensation

(d) Ozonolysis

Answer. (c)

800. Oxidation of p-xylene with acidic potassium dichromate gives (a)

(b)

(c)

(d)

Answer. (a)

801. Cresols on distillation with zinc dust gives

(a) o-Xylene

(b) Benzene

(d) Toluene

Answer. (d)

802. An organic compound (A) has a molecular weight 78 and an empirical formula CH. (A) is resistant to attack by oxidizing agents but undergoes substitution and addition reactions. X-ray analysis shows that the distance between adjacent carbon atoms is 1.39Å (intermediate between single and double bond lengths). The evidence suggests that compound (A) is

(a) Benzene

(b) Cyclohexane

(d) n-Hexane

Answer. (a)

803. Benzene undergoes substitution reaction more easily than addition reaction because

(a) it has a cyclic structure

(b) it has three double bonds

(d) there is delocalization of electrons

Answer. (d)

804. Benzene reacts with concentrated HNO3 in the presence of concentrated H₂SO₄ to give nitrobenzene. This reaction is an example of

(a) Electrophilic addition

(b) Nucleophilic addition

(d) Nucleophilic substitution

Answer. (c)

805. Which of the following agents is used in order to make benzene react with concentrated nitric acid to give nitrobenzene?

(a) Concentrated H₂SO₄

(b) FeCl₃ catalyst

(d) Ultraviolet light

Answer. (a)

806. Which of the following agents is used in order to make benzene react with acetyl chloride to give acetophenone?

(a) Ultraviolet light

(b) AlCl₃ catalyst

(d) Al₂O₃ catalyst

Answer. (b)

807. Which of the following agents is used in order to make benzene react with bromine to give bromobenzene?

(a) Ultraviolet light

(b) Fe catalyst

(d) Al₂O₃ catalyst

Answer. (b)

808. In the Friedel-Craft acetylation of an aromatic ring, the role of the AlCl3 is to

(a) Form a ion.

(b) Function as a Lewis base

(d) Withdraw electrons from the aromatic ring

Answer. (a)

809. The electrophile which is considered to be the active agent in the nitration of benzene is

(a)

(b)

(c)

(d)

Answer. (c)

810. In chlorination of benzene, FeCl3 is used to generate (a)

(b) Cl+

(d) HCl

Answer. (b)

811. In sulfonation of benzene, the attacking species is

(a) H+

(b) SO₂

(d)

Answer. (c)

812.

Consider the following reaction :

The catalyst used to complete the above reaction is

(a) LiAlH₄

(b) AlCl₃

(d) KOH

Answer. (b)

813. Benzene reacts with H₂ at 150°C at 30 atm in the presence of Ni catalyst to give

(a) Cyclohexane

(b) Cyclohexene

(d) No reaction occurs

Answer. (a)

814. Benzene reacts with chlorine in the presence of FeCl₃ catalyst to form

(a) Hexachlorobenzene

(b) Chlorobenzene

(d) Benzyl chloride

Answer. (b)

815. Benzene reacts with acetic anhydride in the presence of AlCl₃ to form

(a) Acetophenone

(b) Benzophenone

(d) Phenyl acetate

Answer. (a)

816. Benzene reacts with benzoyl chloride in the presence of anhydrous aluminium chloride to form

(a) Benzyl chloride

(b) Benzaldehyde

(d) Benzophenone

Answer. (d)

817. Benzene undergoes Friedel-Crafts reaction with isopropyl alcohol in the presence of H₂SO₄ catalyst to give

(a) n-Propylbenzene

(b) Benzophenone

(d) Nothing happens

Answer. (c)

818. Benzene reacts with propene in the presence of H₂SO₄ catalyst to give

(a) n-Propylbenzene

(b) Benzophenone

(d) Nothing happens

Answer. (c)

819. Ozonolysis of benzene gives

(a) Formic acid

(b) Glyoxal

(d) Glycine

Answer. (b)

820. Gammexane is

(a) Hexachloroethane

(b) DDT

(d) TNT

Answer. (c)

821. Which group is an activating substituent?

(a) –NO₃

(b) –Cl

(d) –F

Answer. (c)

822. Which of the following compounds reacts most rapidly with HNO3/H2SO4?

(a) toluene

(b) anisole

(d) benzonitrile

Answer. (b)

823. In electrophilic aromatic substitution reactions a chlorine substituent

(a) is a deactivator and a m-director

(b) is a deactivator and an o,p-director

(d) is an activator and an o,p-director

Answer. (b)

824. Which of the following substituents is an ortho and para director and ring deactivating?

(a) –NH₂

(b) –Cl

(d) –OH

Answer. (b)

825. Which of the following will undergo substitution in the ortho and para

positions rather than in the meta position?

(a) Nitrobenzene

(b) Benzoic acid

(d) Benzaldehyde

Answer. (c)

826. Phenol is an ortho-para director because the hydroxyl group :

(a) donates electrons that increase electron density at ortho and para positions favoring nucleophilic attack.

(b) donates electrons that increase electron density at ortho and para positions favoring electrophilic attack.

(c) donates electrons to the ortho and para positions and attracts electrons away from meta positions favoring nucleophilic attack of the ring.

(d) donates electrons to the ortho and para positions and attracts electrons away from meta positions favoring electrophilic attack on the ring.

Answer. (b)

827. Compared to benzene, nitration of toluene takes place at

(a) Same rate

(b) Faster rate

(d) Can not predict

Answer. (b)

828. Electron-withdrawing groups are meta directors because :

(a) the carbonium ion intermediate has a negative charge on the meta position.

(b) the more stable resonance hybrid occurs with meta attachment of the electrophile.

(d) the carbonium ion intermediate has a positive charge on the meta position. Answer. (b). When the electrophile attaches to the benzene ring, a carbonium ion is formed. This carbonium ion is relatively stable because the charge can be delocalized about the ring. Ortho or para attack results in a resonance form, with the positive charge on the carbon bearing the electron-withdrawing group (highly unstable). This resonance form does not occur with meta placement of the incoming electrophile.

829. Which compound undergoes substitution reactions faster than benzene? (a)

(b)

(c)

(d)

Answer. (d). Remember that activating (electron-donating) groups on benzene result in enhanced electrophilic substitution.

830. Which compound undergoes substitution reactions slower than benzene? (a)

(b)

(c)

(d)

Answer. (c). The halogen (–F) is the only deactivating group because of its electronegativity and its low resonance potential.

831. Which of the following compounds undergoes nitration most readily?

(a) Benzene

(b) Toluene

(d) Benzoic acid

Answer. (b)

832. Which of the following compounds is most readily sulfonated?

(a) Benzene

(b) Chlorobenzene

(d) Nitrobenzene

Answer. (c)

833. p-Nitrotoluene on treatment with chlorine in the presence of FeCl₃ gives

(a) m-Chlorotoluene

(b) 2-Chloro-4-nitrotoluene

(d) 2-Nitro-4-chlorotoluene

Answer. (b)

834. How many isomeric dichlorobenzenes are there?

(a) 3

(b) 6

(d) 12

Answer. (a)

835. Which of the following compounds has maximum dipole moment?

(a) p-Dichlorobenzene

(b) m-Dichlorobenzene

(d) Carbon tetrachloride

Answer. (c)

836. Which of the following reagents is most suitable for preparing chlorobenzene from benzene?

(a) Aqueous chlorine

(b) Chlorine in the presence of ultraviolet light

(d) Chlorine in the presence of FeCl₃

Answer. (d)

837. Which of the reactions between the following pairs of reagents proceeds by a mechanism that may be described as an electrophilic substitution?

(a) Benzene + Br₂/FeBr₃

(b) Propene + Br₂

(d) Ethyl bromide + aq KOH

Answer. (a)

838. Aryl halides are less reactive towards nucleophilic substitution as compared to alkyl halides due to

(a) Inductive effect

(b) Resonance stabilization

(d) Stereoisomerism

Answer. (b)

839. Which of the following compounds would be unaffected by boiling aqueous NaOH?

(a) Chloroethane

(b) Acetaldehyde

(d) Ethyl acetate

Answer. (c)

840. Hydrolysis of benzal chloride gives

(a) Phenol

(b) Benzaldehyde

(d) Benzoyl chloride

Answer. (b)

841. Hydrolysis of benzotrichloride gives

(a) Benzophenone

(b) Benzoic acid

(d) Phenol

Answer. (b)

842.

Which reagent can be used to carry out the following conversion?

(a) HNO₃ + H₂SO₄

(b) NaNO₂

(d) NO₂

Answer. (a)

843.

The following compound is called?

(a) Chloral

(b) DDT

(d) BHC

Answer. (b)

844. DDT is prepared by the reaction of chlorobenzene with (in the presence of conc. H₂SO₄)

(a) Chloral

(b) Chlorine

(d) Carbon tetrachloride

Answer. (a)

845. Which of the following reagents can be used to distinguish between chlorobenzene and allyl chloride?

(a) H₂/Ni

(b) Br2 in CCl₄

(d) NH₂NH₂

Answer. (b)

846. Which of the following reagents can be used to distinguish between chlorobenzene and benzyl chloride?

(a) alcoholic AgNO₃

(b) Br₂ in CCl₄

(d) Br₂ in H₂O

Answer. (a)

847. An organic compound (A) was heated with a solution of NaOH. The resulting solution was cooled, acidified with dilute HNO₃, and then AgNO₃ solution was added. This gave a white precipitate. The compound (A) may be

(a)

(b)

(c)

(d)

Answer. (b)

848. Which of the following statements is False/Incorrect about nitrobenzene?

(a) is formed by nitration of benzene at temperatures below 60°C.

(b) can be further nitrated to give m-dinitrobenzene.

(d) can be reduced with Sn/HCl to give aniline.

Answer. (c)

849. Which of the following compounds reacts least rapidly in electrophilic substitution reactions?

(a) Nitrobenzene

(b) Phenol

(d) Toluene

Answer. (a)

850. Nitrobenzene reacts with Br2 in the presence of FeCl₃ to give

(a) o-chloronitrobenzene

(b) o-bromonitrobenzene

(d) m-bromonitrobenzene

Answer. (d)

851. Nitration of nitrobenzene with HNO₃/H₂SO₄ gives :

(a) m-dinitrobenzene

(b) o-dinitrobenzene

(d) m-nitrobenzenesulfonic acid

Answer. (a)

852. Nitrobenzene undergoes reduction with zinc and KOH to give

(a) Aniline

(b) Hydrazobenzene

(d) None of these

Answer. (b)

853. Reduction of p-nitrotoluene with Sn + HCl gives :

(a) p-methylaniline

(b) Toluene

(d) N-Methylaniline

Answer. (a)

854. Which of the following statements is false about aniline?

(a) It is a primary aromatic amine.

(b) It is a weak base which forms salts with acids.

(d) It can be prepared by the reduction of nitrobenzene with tin and HCl.

Answer. (c)

855. Which of the following statements is correct about aniline?

(a) is weak acid.

(b) diazotizes to benzenediazonium chloride when treated with ice-cold nitrous acid.

(d) gives an intense green color with a suspension of bleaching powder in water.

Answer. (b)

856. Which of the following statements is false about benzylamine?

(a) can be prepared by reduction of benzonitrile with LiAlH₄.

(b) cannot be prepared by reduction of benzamide with LiAlH₄.

(d) reacts with KMnO₄ to give benzoic acid.

Answer. (b)

857. Aniline is prepared by

(a) the reaction of benzene with ammonia

(b) the reduction of nitrobenzene with Sn/HCl

(d) the reaction of nitrobenzene with I₂/NaOH

Answer. (b)

858. Benzamide reacts with Br2 and KOH to give

(a) Benzene

(b) Benzylamine

(d) Benzonitrile

Answer. (b)

859. When ammonia is added to an alkyl halide, in the presence of base :

(a) primary amines form

(b) amides form

(d) quaternary ammonium salts form

Answer. (a). Salts of 1° amines can be prepared from ammonia and alkyl halides. Treating the ammonium salt with base gives a 1° amine.

860. Aniline reacts with bromine water to form

(a) Bromobenzene

(b) m-Bromoaniline

(d) o- plus p-Bromoaniline

Answer. (c)

861. Which of the following will give a precipitate with excess bromine water?

(a) Bromobenzene

(b) Aniline

(d) Toluene

Answer. (b)

862. Aniline reacts with nitrous acid at low temperatures to give

(a) a N-nitrosoamine

(b) a nitrile

(d) a nitrite salt

Answer. (c)

863. When aniline is heated with chloroform and alcoholic KOH, the product is

(a) Benzonitrile

(b) p-Chloroaniline

(d) m-Chloroaniline

Answer. (c)

864. Aniline reacts with acetic anhydride to give :

(a) N-Methylaniline

(b) p-Aminoacetophenone

(d) m-Aminoacetophenone

Answer. (c)

865. Aniline undergoes oxidation with Na₂Cr₂O₇/H₂SO₄ to give

(a) Schiff's base

(b) p-Benzoquinone

(d) Benzoic acid

Answer. (b)

866. Which of the following reagents does not react with aniline?

(a) Acetyl chloride

(b) Acetic anhydride

(d) Nitrous acid

Answer. (c)

867.

Rank the following compounds in order of increasing base strength :

(a) 1, 2, 3

(b) 3, 2, 1

(d) 2, 1, 3

Answer. (c). The aromatic amines are weaker bases than the nonaromatic cyclic amines because the lone-pair electrons on nitrogen are delocalized over the aromatic ring. This delocalization stabilizes the compound but also decreases the ability of the nitrogen to act as a base. Compound (3) is a stronger base than aniline because of the electron-releasing substituent on the ring.

868.

Rank the following compounds in order of increasing base strength :

(a) 1, 2, 3, 4

(b) 4, 2, 3, 1

(d) 4, 3, 1, 2

Answer. (d). Of the aromatic amines, the weakest base is the one with the electron-withdrawing substituent: (4) is the weakest followed by aniline (3). Compound (2) is the strongest base because its electrons are not delocalized effectively into the aromatic ring, and it is therefore a primary amine, and its pK_a is slightly lower than that of ammonia.

869. Which of the following compounds is most basic?

(a) Aniline

(b) Benzylamine

(d) p-nitroaniline

Answer. (b)

870. Which of the following is most basic?

(a) CH₃NH₂

(b) (CH₃)₃N

(d)

Answer. (c)

871. Which of the following is most basic?

(a) (CH₃)₂NH

(b)

(c)

(d) NH₃

Answer. (a)

872. Which of the following compounds is most basic? (a)

(b)

(c)

(d)

Answer. (a)

873. Which of the following is least basic?

(a) Aniline

(b) p-Nitroaniline

(d) Trimethylamine

Answer. (b)

874. Which of the following is least basic?

(a) CH₃NH₂

(b) (CH₃)₃N

(d)

Answer. (d)

875. Which of the following compounds is least basic?

(a)

(b)

(c)

(d)

Answer. (c)

876. Which of the following compounds will be most soluble in water at room temperature?

(a) Phenol

(b) Phenylammonium chloride

(d) Benzylamine

Answer. (b)

877. The diazonium salts are the reaction products of the reaction of nitrous acid with

(a) primary aliphatic amines

(b) primary aromatic amines

(d) secondary aromatic amines

Answer. (b)

878. Preparation of a diazonium salt from a primary aromatic amine is known as :

(a) Coupling reaction

(b) Sandmeyer reaction

(d) Corey-House synthesis

Answer. (c)

879. Which of the following reagents is used to prepare benzenediazonium

chloride from aniline?

(a) NaNO₂ + HCl

(b) LiAlH₄

(d) NaOH

Answer. (a)

880. Which of the following are optimum temperature conditions for making benzenediazonium chloride from aniline?

(a) 0°C to 10°C

(b) 20°C to 25°C

(d) 45°C to 50°C

Answer. (a)

881. Benzenediazonium chloride reacts with warm water to give

(a) Aniline

(b) Phenol

(d) Chlorobenzene

Answer. (b)

882. Bromobenzene can be prepared by treating aniline with

(a) Conc HBr

(b) Br₂/FeBr₃

(b) CuBr

(d) Nitrous acid then CuBr

Answer. (d)

883. Chlorobenzene can be prepared by treatment of aniline with

(a) Cuprous chloride

(b) Chlorine in the presence of UV light

(d) Chlorine in the presence of FeCl₃

Answer. (c)

884. Iodobenzene can be prepared by

(a) treating chlorobenzene with I2 using FeCl₃ catalyst.

(b) treating phenol with I2 in NaOH solution.

(d) treating benzene with CH3I using AlCl₃ catalyst.

Answer. (c)

885. Benzenediazonium chloride reacts with KI to form :

(a) Benzenediazonium iodide

(b) m-Diiodobenzene

(d) o- plus p-Diiodobenzene

Answer. (c)

886.

What is the major product of the following reaction?

(a) Benzonitrile

(b) Benzoic acid

(d) Benzenediazonium chloride

Answer. (a)

887. Benzenediazonium chloride reacts with hypophosphorus acid to form :

(a) Phenol

(b) Benzaldehyde

(d) Benzene

Answer. (d)

888. Benzenediazonium chloride reacts with phenol to form :

(a) p-chlorophenol

(b) Chlorobenzene

(d) DDT

Answer. (c)

889. Phenol is used

(a) in alcoholic beverages

(b) as anesthetic

(d) as moth repellant

Answer. (c)

890. Which of the following compounds is aspirin

(a) Methyl salicylate

(b) Salicylic acid

(d) Acetylsalicylic acid

Answer. (d)

891. When phenol is treated with neutral FeCl₃ solution, it develops

(a) Violet color

(b) Yellow color

(d) Nothing happens

Answer. (a)

892. Which of the following compounds will react with PCl₅ least vigorously?

(a) Ethanol

(b) Acetic acid

(d) Benzoic acid

Answer. (c)

893. Sodium phenoxide reacts with CO2 at 125°C under 5 atm pressure to give salicylic acid. This reaction is called

(a) Kolbe's reaction

(b) Perkin reaction

(d) HVZ reaction

Answer. (a)

894. Phenol reacts with excess bromine water to give

(a) o- plus p-Bromophenol

(b) Bromobenzene

(d) m-Bromophenol

Answer. (c)

895. Resorcinol on distillation with zinc dust gives

(a) Benzene

(b) Cyclohexane

(d) m-Xylene

Answer. (a)

896. Bakelite has the following characteristics

(a) A polymer made from phenol and formaldehyde

(b) A thermosetting plastic

(d) All of the above

Answer. (d)

897. Anisole is formed when phenol is treated with

(a) CH₃I/NaOH

(b) CH₃CH₂I/NaOH

(d) Acetic anhydride

Answer. (a)

898. Anisole on heating with concentrated HI gives

(a) Iodobenzene

(b) Phenol + CH₃I

(d) Phenol + CH₃OH

Answer. (b)

899. Which group forms the strongest H-bonds to water molecules?

(a) Alcohols

(b) Ethers

(d) All equally strong

Answer. (c)

900. The compound which is most capable of hydrogen bonding is :

(a) CH₃OCH₂CH₃

(b) CH₃CH₂CH₂CH₃

(c)

(d) CH₃CH₂—S—S—CH₂CH₃

Answer. (c)

901.

Rank the following molecules in decreasing order of boiling points :

(a) (3) > (2) > (1)

(b) (2) > (3) > (1)

(d) (2) > (1) > (3)

Answer. (a). Hydroxyl groups can more easily form intramolecular H-bonds in the ortho position than in the meta or para positions. These intramolecular H-bonds decrease boiling point. Therefore, compound (3) has a higher boiling point than compound (2). Compound (2), with two hydroxyl groups, has a still higher boiling point than phenol.

902.

Rank the following compounds in order of increasing boiling point :

(a) (1) < (2) < (3)

(b) (3) < (1) < (2)

(d) (3) < (2) < (1)

Answer. (d)

903. Phenol is acidic because of

(a) Resonance

(b) Electromeric effect

(d) Peroxide effect

Answer. (a)

904. Which of the following has the most acidic proton?

(a) Thiol

(b) Alcohol

(d) Ether Answer. (c) 905. Phenol is

(a) stronger acid than acetic acid

(b) weaker acid than acetic acid

(d) weaker base than methylamine

Answer. (b)

906. Which of the following compounds is least acidic?

(a) HCl

(b) Phenol

(d) Picric acid

Answer. (c)

907. Which of the following compounds is least acidic?

(a) Formic acid

(b) Ethanol

(d) Phenol

Answer. (b)

908. Which of the following compounds is most acidic?

(a) Formic acid

(b) Ethanol

(d) Phenol

Answer. (a)

909. Which of the following compounds is most acidic?

(a) Water

(b) Cyclohexanol

(d) Phenol

Answer. (d)

910. Which one is most acidic?

(a) Hexanol

(b) Phenol

(d) Diisopropyl ether

Answer. (b)

911. Which of the following compounds is most acidic?

(a) o-Cresol

(b) p-Nitrophenol

(d) p-Chlorophenol

Answer. (b)

912. Which of the following compounds is most acidic?

(a) Phenol

(b) m-Nitrophenol

(d) m-Bromophenol

Answer. (b)

913.

Which molecule is the most acidic?

(a) (1)

(b) (2)

(d) (2) and (3) have similar acidities

Answer. (b). Acidity is enhanced when the conjugate base is further stabilized. By placing an electron-withdrawing group on the ring, the phenoxide ion is further stabilized when the charge spreads over more atoms (greater delocalization). The methoxy group is electron-releasing and destabilizes the phenoxide.

914.

Which of the following compounds is most acidic?

Answer. (c)

915.

Which of the following compounds is least acidic?

Answer. (b)

916. Arrange the following compounds in order of increasing acidity :

(a) (1) < (3) < (2)

(b) (1) < (2) < (3)

(d) (2) < (1) < (3)

Answer. (a)

917. Phenols can be easily distinguished from alcohols because

(a) phenols are soluble in NaOH, but alcohols are not

(b) alcohols are soluble in NaOH, but phenols are not

(d) alcohols are soluble in NaHCO₃, but phenols are not

Answer. (a)

918. Benzoyl chloride reacts with hydrogen in the presence of palladium and barium sulfate to give :

(a) Benzyl alcohol

(b) Benzaldehyde

(d) Benzophenone

Answer. (b). This is Rosenmund reduction.

919. Cinnamaldehyde is prepared by the treatment of :

(a) benzaldehyde with acetaldehyde in the presence of NaOH

(b) benzaldehyde with formaldehyde in the presence of NaOH

(d) benzophenone with formaldehyde in the presence of NaOH

Answer. (a)

920. Benzaldehyde reacts with methylmagnesium iodide (followed by hydrolysis) to form

(a) 1-Phenylethanol

(b) Acetophenone

Answer. (a)

921. Which of the following will undergo Aldol condensation?

(a) Acetone

(b) Benzaldehyde

Answer. (a)

922. When benzaldehyde is heated with concentrated NaOH, it gives :

(a) Benzyl alcohol

(b) Sodium benzoate

(d) Benzyl alcohol + Sodium benzoate

Answer. (d). This is Cannizzaro reaction.

923. Benzaldehyde reacts with acetic anhydride in the presence of sodium acetate at 180°C to give :

(a) Mandelic acid

(b) Cinnamic acid

(d) Benzoic acid

Answer. (b). This is Perkin reaction.

924. Which of the following reagents will give an addition reaction with benzaldehyde?

(a) NaHSO₃

(b) I₂/NaOH

(d)

Answer. (a)

925. Benzaldehyde reacts with a mixture of concentrated sulfuric acid and nitric acid to give

(a) p-Nitrobenzaldehyde

(b) o-Nitrobenzaldehyde

(d) m-Nitrobenzaldehyde

Answer. (d)

926. Acetophenone reacts with Br2 in the presence of FeCl₃ to form :

(a) m-Bromoacetophenone

(b) m-Dibromobenzene

(d) p-Dibromobenzene

Answer. (a)

927. Which of the following statements is NOT correct :

(a) Tollens' test is given by both aliphatic and aromatic aldehydes.

(b) Fehling's test is given by aliphatic aldehydes. It is not given by aromatic aldehydes.

(d) Lucas test is given by both aliphatic and aromatic aldehydes.

Answer. (d)

928. Benzaldehyde can be distinguished from acetophenone by using :

(a) Tollens' reagent

(b) Lucas reagent

(d) All of these

Answer. (a)

929. Benzaldehyde does not react with

(a) Tollens' reagent

(b) Phenylhydrazine

(d) NaHSO₃

Answer. (c)

930. Which of the following will give a positive Tollens' test? (a)

(b)

(c)

(d)

Answer. (c)

931. Which of the following compounds yields a yellow precipitate when warmed with a mixture of iodine in aqueous sodium hydroxide?

(a) Acetophenone

(b) Benzaldehyde

(d) Propanal

Answer. (a)

932. A compound (A) gave a positive iodoform reaction and left a solution containing a monocarboxylate ion. Which of the following could (A) be?

(a)

(b)

(c)

(d)

Answer. (c)

933. How many isomers containing a benzene ring correspond to the formula C₆H₄(COOH)₂?

(a) 1

(b) 2

(d) 4

Answer. (c)

934. Which of the following is not a carboxylic acid?

(a) Malonic acid

(b) Acetic acid

(d) Adipic acid

Answer. (c)

935. Phenylmagnesium bromide reacts with CO₂ followed by acid-hydrolysis to form :

(a) Phenol

(b) Benzoic acid

(d) Acetophenone

Answer. (b)

936. Benzoic acid and diphenyl ketone are both solids insoluble in water. A mixture of these compounds can be separated if we

(a) add the mixture to a solution of NaOH in water, and filter.

(b) add the mixture to a solution of HCl in water, and filter.

(d) It is impossible to separate a mixture of two solids when both are insoluble in water.

Answer. (a)

937. Which of the following reactions does not produce benzene as one of the products?

(a) Treating benzenediazonium chloride with H₃PO₂

(b) Distilling phenol with zinc dust

(d) Fusing sodium benzenesulfonate with NaOH

Answer. (d)

938. Which of the following esters produces butyric acid and phenol on hydrolysis?

(a) Phenyl butyrate

(b) Butyl benzoate

(d) Phenyl propionate

Answer. (a)

939. Benzoyl chloride on basic-hydrolysis (NaOH/H₂O) gives :

(a) Benzoic acid

(b) Methyl benzoate

(d) Ethyl benzoate

Answer. (c)

940. Sodium benzoate on heating with soda-lime gives :

(a) Sodium phenoxide

(b) Benzene

(d) Benzophenone

Answer. (b)

941.

The product of the following reaction is :

(a)

(b)

(c)

(d)

Answer. (b)

942. Methyl benzoate on hydrolysis gives

(a) Acetic acid

(b) Benzoic acid

(d) Phenylacetic acid

Answer. (b)

943. Aspirin is produced by heating salicylic acid with

(a) acetic anhydride in the presence of phosphoric acid

(b) benzoic anhydride in the presence of phosphoric acid

(d) phenol in the presence of sulfuric acid

Answer. (a)

944. Oil of Wintergreen (Methyl salicylate) is obtained by treating salicylic acid with

(a) Methane at 150°C

(b) CH₃OH and conc. H₂SO₄

(d) NaOH and then CH₃OH

Answer. (b)

945. Which of the following statements is true :

(a) o-Nitrobenzoic acid is more acidic than p-nitrophenol

(b) o-Nitrobenzoic acid is less acidic than p-nitrophenol

(d) None of these statements is true

Answer. (a)

946. The order of increasing acidity is :

(a) chloroacetic acid > formic acid > benzoic acid

(b) benzoic acid > formic acid > chloroacetic acid

(d) not determinable from available data

Answer. (a)

947. Which of the following is the strongest acid?

(a) Trichloroacetic acid

(b) Phenol

(d) Benzoic acid

Answer. (a)

948. Which of the following is the strongest acid?

(a) Ethanol

(b) Phenol

(d) Benzoic acid

Answer. (d)

949. Which acid is weaker than benzoic acid?

(a) p-Methylbenzoic acid

(b) p-Chlorobenzoic acid

(d) o-Chlorobenzoic acid

Answer. (a)

950. Compound (A) when reacted with PCl5 and then with ammonia gave (B). Compound (B) when treated with bromine and NaOH, produced (C). Compound

(a) o-Toluic acid

(b) o-Chlorotoluene

(d) o-Bromotoluene

Answer. (a)

951. The reason why materials appear colored is

(a) The selective absorption of spectral colors

(b) The interaction between the light and the electrons of the dye molecules

(d) All of these

Answer. (d)

952. Which of the following is a chromophore?

(a) –NO₂

(b) –SO₃H

(d) –COOH

Answer. (a)

953. Which of the following is an auxochrome?

(a) –N=O

(b) –NO₂

(d) –OH

Answer. (d)

954. The water-solubility of dyes can be increased by introducing

(a) SO₃Na groups

(b) COOH groups

(d) All of these

Answer. (d)

955. Which dyes become linked to the fibre by chemical reaction?

(a) Acid dyes

(b) Direct dyes

(d) None of these

Answer. (a)

956. All carbon atoms in naphthalene are

(a) sp hybridized

(b) sp2 hybridized

(d) None of these

Answer. (b)

957. Naphthalene undergoes oxidation with Na₂Cr₂O₇ / H₂SO₄ to form

(a) Phthalic acid

(b) Phenylacetic acid

(d) Benzoic acid

Answer. (a)

958. Naphthalene undergoes reduction with H₂ in the presence of Ni catalyst at high temperature and pressure to give

(a) Phthalic acid

(b) Decalin

(d) Tetralin

Answer. (b)

959. Naphthalene undergoes nitration with HNO₃/H₂SO₄ at 60°C to give mainly

(a) 1-Nitronaphthalene

(b) 1,2-Dinitronaphthalene

(d) 1,5-Dinitronaphthalene

Answer. (a)

960. All carbon atoms in anthracene are

(a) sp hybridized

(b) sp3 hybridized

(d) None of these

Answer. (c)

961. Anthracene undergoes electrophilic substitution reactions mainly at

(a) C-1

(b) C-2

(d) C-1 and C-2

Answer. (c)

962. Anthracene undergoes oxidation with O₂/V₂O₅ at 500°C to give

(a) Benzoic acid

(b) Anthraquinone

(d) Benzophenone

Answer. (b)

963. Which of the following is not a heterocyclic compound? (a)

(b)

(c)

(d)

Answer. (c)

964. Which of the following heterocyclic compounds is not aromatic?

(a) Pyridine

(b) Pyrrole

(d) Piperidine

Answer. (d)

965. The ‘N’ atom in pyridine is

(a) sp3 hybridized

(b) sp2 hybridized

(d) cannot be predicted

Answer. (b)

966. Pyridine has a delocalized π molecular orbital containing

(a) 4 electrons

(b) 6 electrons

(d) 12 electrons

Answer. (b)

967. Pyrrole is less basic than pyridine because the lone-pair of electrons on N- atom in pyrrole

(a) is part of the delocalized π molecular orbital.

(b) is not part of the delocalized π molecular orbital.

(d) resides in sp hybrid orbital

Answer. (a)

968. Pyridine is less basic than trimethylamine because the lone-pair of electrons on N-atom in pyridine resides in

(a) sp2 hybrid orbital

(b) sp hybrid orbital

(d) p-orbital

Answer. (a)

969. Pyridine reacts with HCl to form

(a) Pyridinium chloride

(b) 2-Chloropyridine

(d) All of these

Answer. (a)

970. Pyridine undergoes electrophilic substitution with fuming H₂SO₄ at 350°C to give

(a) 2-Pyridinesulfonic acid

(b) 4-Pyridinesulfonic acid

(d) None of these

Answer. (c)

971. Pyridine reacts with a mixture of KNO₃ and H₂SO₄ at 300°C to give

(a) 1-Nitropyridine

(b) 2-Nitropyridine

(d) 4-Nitropyridine

Answer. (c)

972. Pyridine undergoes nuclophilic substitution with NaNH₂ at 100°C to form

(a) 2-Aminopyridine

(b) 3-Aminopyridine

(d) None of these

Answer. (a)

973. Which of the following reagents will react with pyrrole to form 2- formylpyrrole?

(a) HCOOH

(b) CHCl₃/KOH

(d) (CH₃CO)₂O/SnCl₄

Answer. (b)

974. Furan reacts with ammonia in the presence of alumina at 400°C to give

(a) Pyridine

(b) Furfural

(d) Furoic acid

Answer. (c)

975. Which of the following reagents will react with furan to form 2-furansulfonic acid?

(a) SO₃ in pyridine at 100°C

(b) Dilute H₂SO₄ at 200°C

(d) Dilute H₂SO₄ at 100°C

Answer. (a)

976. When aniline is heated with glycerol in the presence of sulfuric acid and nitrobenzene, it gives quinoline. This reaction in called

(a) Fischer synthesis

(b) Skraup synthesis

(d) Corey-House synthesis

Answer. (b)

977. Quinoline undergoes nucleophilic substitution on heating with NaNH₂ to give

(a) 2-Aminoquinoline

(b) 4-Aminoquinoline

(d) 8-Aminoquinoline

Answer. (a)

978. Orlon is prepared by the polymerisation of

(a) Vinyl cyanide

(b) Allyl alcohol

(d) Allyl chloride

Answer. (a)

979. Which of the following statements is true about terpenes?

(a) They are a class of lipids that can be isolated from plants.

(b) They contain carbon atoms in multiples of five.

(d) All of the above

Answer. (d)

980. How many isoprene units are in a sesquiterpene?

(a) 1

(b) 2

(d) 4

Answer. (c)

981. What is the IUPAC name for isoprene?

(a) 1,3-pentadiene

(b) 2,4-pentadiene

(d) 2-methyl-1,3-butadiene

Answer. (d)

982. How many isoprene units are present in sesquiterpenes?

(a) 1

(b) 2

(d) 4

Answer. (c)

983. Teflon is prepared by the polymerization of

(a) Butadiene

(b) Vinyl cyanide

(d) Tetrafluoroethylene

Answer. (d)

984. Bakelite is obtained from :

(a) Phenol and formaldehyde

(b) Adipic acid and hexamethylene diamine

(d) Neoprene

Answer. (a)

985. Nylon-6,6 is obtained from :

(a) Adipic acid and hexamethylene diamine

(b) Tetrafluoroethylene

(d) Vinylbenzene

Answer. (a)

986. Neoprene is a polymer of the following monomer

(a) Chloroprene

(b) Isoprene

(d) Isopentene

Answer. (a)

987. Which of the following is a thermosetting polymer?

(a) Bakelite

(b) Nylon-6,6

(d) Teflon

Answer. (a)

988. Which of the following is an example of a condensation polymer?

(a) Nylon-6,6

(b) Teflon

(d) Orlon

Answer. (a)

989. Which of the following polymers contain nitrogen

(a) PVC

(b) Teflon

(d) Terylene

Answer. (c)

990. Adipic acid reacts with hexamethylene diamine to form

(a) Bakelite

(b) Nylon-6,6

(d) Nylon-6,8

Answer. (b)

991. Ethylene glycol reacts with dimethyl terephthalate to form

(a) Nylon-6,6

(b) Teflon

(d) Orlon

Answer. (c)

992. Natural rubber is a polymer of

(a) Propene

(b) Isoprene

(d) Phenol

Answer. (b)

993. The monomers for Buna-S are 1,3-butadiene and

(a) Ethylene glycol

(b) Adipic acid

(d) Caprolactum

Answer. (c)

994. Which of the following statements is not true?

(a) Natural rubber is a hydrocarbon.

(b) Natural rubber is made of isoprene units

(d) Natural rubber can be vulcanized.

Answer. (c)

995. Which of the following are addition polymers?

I. Polypropylene

II. Teflon

III. Nylon

(a) Only I

(b) Only II

(d) both I and II

Answer. (d)

996. Which of the following are condensation polymers?

I. Polypropylene

II. Teflon

III. Nylon

(a) Only I

(b) Only II

(d) Both II and III

Answer. (c)

997. Which one of the following is used to make Teflon?

(a) Fluoroethene

(b) 1,1,4,4-tetrafluorobutadiene

(d) Tetrafluoroethylene

Answer. (d)

998. Vulcanization is the process of cross-linking polymer chains in rubber using

(a) Sulfur.

(b) Formaldehye.

(d) Ethylene glycol.

Answer. (a)

999. What is the purpose of plasticizers?

(a) Harden plastics

(b) Soften plastics

(d) Cross-link polymer chains

Answer. (b)

1000. Polymers which soften on heating and harden when cooled are

(a) Cross-linked polymers

(b) Copolymers

(d) Thermoplastics

Answer. (d)

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