ROUTERA


Chapter 13 Organic Compounds Containing Nitrogen (Amines)

Class 12th Chemistry Chapter MCQs


1. Which of the following is an example of a primary amine?

a) CH3NH2
b) (CH3)2NH
c) (CH3)3N
d) NH3

Answer: a) CH3NH2
Explanation: CH3NH2 (methylamine) is a primary amine, where one alkyl group (methyl group) is attached to the nitrogen atom.


2. Which of the following is a property of amines?

a) They are acidic in nature
b) They react with acids to form salts
c) They do not form hydrogen bonds
d) They are non-basic

Answer: b) They react with acids to form salts
Explanation: Amines are basic in nature and react with acids to form amine salts, e.g., methylamine reacts with hydrochloric acid to form methylammonium chloride.


3. Which of the following amines is most basic?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: c) Dimethylamine
Explanation: Dimethylamine is more basic than aniline and methylamine because the electron-donating effect of the two methyl groups increases the electron density on the nitrogen atom, making it more basic.


4. Which of the following is the correct IUPAC name for the compound CH3CH2NH2?

a) Ethylamine
b) N-Ethylamine
c) Ethanolamine
d) Aminoethane

Answer: a) Ethylamine
Explanation: CH3CH2NH2 is named ethylamine, where the amine group is attached to an ethyl group.


5. What is the product of the reaction between an amine and an alkyl halide?

a) Alcohol
b) Ammonium salt
c) Amino acid
d) Alkene

Answer: b) Ammonium salt
Explanation: When an amine reacts with an alkyl halide, an ammonium salt is formed due to nucleophilic substitution.


6. Which of the following is a characteristic test for primary amines?

a) Acetylation
b) Hinsberg test
c) Bromine water test
d) Schiff's test

Answer: b) Hinsberg test
Explanation: The Hinsberg test is used to distinguish primary amines from secondary and tertiary amines by forming soluble or insoluble derivatives.


7. Which of the following is a secondary amine?

a) CH3NH2
b) (CH3)2NH
c) (CH3)3N
d) NH3

Answer: b) (CH3)2NH
Explanation: (CH3)2NH (dimethylamine) is a secondary amine, where two methyl groups are attached to the nitrogen atom.


8. Which of the following is the product when aniline reacts with bromine water?

a) Benzene
b) Phenyl amine
c) 2,4,6-Tribromoaniline
d) Benzoic acid

Answer: c) 2,4,6-Tribromoaniline
Explanation: When aniline reacts with bromine water, a substitution reaction occurs, resulting in the formation of 2,4,6-tribromoaniline.


9. Which of the following compounds can act as a Lewis base?

a) Ammonia
b) Aniline
c) Methylamine
d) All of the above

Answer: d) All of the above
Explanation: All amines (ammonia, aniline, methylamine) act as Lewis bases because nitrogen has a lone pair of electrons, which can donate to an electron-deficient species.


10. Which of the following methods is used to prepare aniline?

a) Reduction of nitrobenzene
b) Nitration of benzene
c) Friedel-Crafts acylation
d) Hydrolysis of benzamide

Answer: a) Reduction of nitrobenzene
Explanation: Aniline can be prepared by the reduction of nitrobenzene using reducing agents like tin and hydrochloric acid.


11. Which of the following is a method of synthesizing amines from nitriles?

a) Reduction
b) Oxidation
c) Hydrolysis
d) Dehydration

Answer: a) Reduction
Explanation: Nitriles can be reduced to amines using reducing agents like LiAlH4 or catalytic hydrogenation.


12. Which of the following is the basicity order of the compounds?

a) Aniline > Ethylamine > Methylamine
b) Methylamine > Ethylamine > Aniline
c) Ethylamine > Methylamine > Aniline
d) Methylamine > Aniline > Ethylamine

Answer: b) Methylamine > Ethylamine > Aniline
Explanation: Methylamine is more basic than ethylamine due to the electron-donating effect of the methyl group. Aniline is less basic because the lone pair on nitrogen is delocalized into the aromatic ring.


13. Which of the following amines undergoes the Hofmann degradation reaction?

a) Aniline
b) Methylamine
c) Ethylamine
d) Aromatic amines

Answer: b) Methylamine
Explanation: The Hofmann degradation reaction involves the removal of the amine group from primary amides, resulting in the formation of a primary amine with one fewer carbon atom. Methylamine undergoes this reaction.


14. Which of the following is a primary amine?

a) Aniline
b) Butylamine
c) Dimethylamine
d) Trimethylamine

Answer: b) Butylamine
Explanation: Butylamine (C4H9NH2) is a primary amine, with a single butyl group attached to the nitrogen atom.


15. Which of the following amines will show positive results in the diazotization reaction?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: a) Aniline
Explanation: Aniline (C6H5NH2) can undergo diazotization to form a diazonium salt, which is a characteristic reaction of primary aromatic amines.


16. Which of the following compounds will not form an amide on reaction with an acyl chloride?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: b) Methylamine
Explanation: Methylamine, being a primary aliphatic amine, does not readily form an amide with an acyl chloride under normal conditions.


17. Which of the following statements is correct for tertiary amines?

a) They are highly basic
b) They do not undergo the Hinsberg test
c) They are weakly basic
d) They undergo electrophilic substitution reactions easily

Answer: b) They do not undergo the Hinsberg test
Explanation: Tertiary amines do not react with benzene sulfonyl chloride in the Hinsberg test, which is used to distinguish primary and secondary amines.


18. What is the product of the reaction between an amine and an acid chloride?

a) Ammonium salt
b) Amide
c) Alcohol
d) Nitrile

Answer: b) Amide
Explanation: When an amine reacts with an acid chloride, an amide is formed through nucleophilic acyl substitution.


19. Which of the following compounds is formed when aniline is treated with nitrous acid?

a) Benzene
b) Benzoic acid
c) Diazonium salt
d) Nitrobenzene

Answer: c) Diazonium salt
Explanation: Aniline reacts with nitrous acid to form a diazonium salt, which is an important intermediate in organic synthesis.


20. What is the primary product of the reaction between ammonia and an alkyl halide?

a) Alkene
b) Primary amine
c) Tertiary amine
d) Ammonium salt

Answer: b) Primary amine
Explanation: Ammonia reacts with an alkyl halide to form a primary amine through a nucleophilic substitution reaction.


21. Which of the following is the correct IUPAC name for the compound CH3NHCH3?

a) Dimethylamine
b) Methylamine
c) Ethylamine
d) N-Methylamine

Answer: a) Dimethylamine
Explanation: CH3NHCH3 is dimethylamine, where two methyl groups are attached to the nitrogen atom.


22. What is the effect of the electron-donating group on the basicity of amines?

a) It decreases the basicity
b) It increases the basicity
c) It does not affect the basicity
d) It makes amines acidic

Answer: b) It increases the basicity
Explanation: Electron-donating groups increase the electron density on nitrogen, enhancing its ability to donate electrons and thus increasing basicity.


23. Which of the following is the IUPAC name for C6H5CH2NH2?

a) Benzenamine
b) Benzylamine
c) Phenylamine
d) Aniline

Answer: b) Benzylamine
Explanation: C6H5CH2NH2 is benzylamine, where the amine group is attached to a benzyl group (C6H5CH2-).


24. Which of the following compounds reacts with bromine to form a white precipitate of 2,4,6-tribromoaniline?

a) Methylamine
b) Aniline
c) Dimethylamine
d) Butylamine

Answer: b) Aniline
Explanation: Aniline reacts with bromine in water to form 2,4,6-tribromoaniline, a characteristic reaction of aromatic amines.


25. Which of the following statements about amines is correct?

a) Amines are acidic in nature
b) Amines do not form hydrogen bonds
c) Amines are basic in nature
d) Amines are non-polar

Answer: c) Amines are basic in nature
Explanation: Amines are basic due to the lone pair of electrons on the nitrogen atom that can accept protons.


26. Which of the following methods is used for the preparation of primary amines from alkyl halides?

a) Reduction with LiAlH4
b) Substitution with ammonia
c) Dehydrohalogenation
d) Nitration

Answer: b) Substitution with ammonia
Explanation: Alkyl halides react with ammonia to form primary amines through a nucleophilic substitution reaction.


27. Which of the following amines is used in the synthesis of dyes and other organic compounds?

a) Methylamine
b) Aniline
c) Dimethylamine
d) Ethylamine

Answer: b) Aniline
Explanation: Aniline is widely used in the manufacture of dyes and other organic compounds, including pharmaceuticals.


28. Which of the following amines is commonly used as a local anesthetic?

a) Methylamine
b) Aniline
c) Lidocaine
d) Dimethylamine

Answer: c) Lidocaine
Explanation: Lidocaine, a derivative of an amine, is commonly used as a local anesthetic in medical practices.


29. Which of the following is the product of the reaction between an amine and nitrous acid (HNO2)?

a) Diazonium salt
b) Amide
c) Alkene
d) Alcohol

Answer: a) Diazonium salt
Explanation: Primary aromatic amines react with nitrous acid to form diazonium salts, which are intermediates in azo dye synthesis.


30. What is the order of basicity of the following amines? Aniline, methylamine, dimethylamine.

a) Dimethylamine > Methylamine > Aniline
b) Methylamine > Dimethylamine > Aniline
c) Aniline > Methylamine > Dimethylamine
d) Aniline > Dimethylamine > Methylamine

Answer: a) Dimethylamine > Methylamine > Aniline
Explanation: Dimethylamine is the most basic because of the strong electron-donating effect of the methyl groups, followed by methylamine and then aniline, which has its lone pair of electrons delocalized into the aromatic ring.


31. Which of the following is the correct IUPAC name for the compound C6H5NH2?

a) Benzenamine
b) Aniline
c) Phenylamine
d) Aminobenzene

Answer: b) Aniline
Explanation: C6H5NH2 is aniline, an aromatic amine, where the amine group is directly attached to a benzene ring.


32. Which of the following reagents is used for the preparation of amines from nitriles?

a) LiAlH4
b) NaOH
c) HCl
d) H2O

Answer: a) LiAlH4
Explanation: Lithium aluminium hydride (LiAlH4) is used to reduce nitriles to amines.


33. Which of the following amines is used in the preparation of dyes?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: a) Aniline
Explanation: Aniline is used in the preparation of various dyes, particularly azo dyes.


34. Which of the following amines is formed by the reduction of a nitro compound?

a) Dimethylamine
b) Aniline
c) Ethylamine
d) Benzylamine

Answer: b) Aniline
Explanation: Aniline is formed by the reduction of nitrobenzene using reducing agents like tin and hydrochloric acid.


35. What is the effect of alkyl substitution on the basicity of amines?

a) Alkyl groups decrease the basicity
b) Alkyl groups do not affect the basicity
c) Alkyl groups increase the basicity
d) Alkyl groups increase the acidity

Answer: c) Alkyl groups increase the basicity
Explanation: Alkyl groups are electron-donating groups and increase the electron density on nitrogen, thus increasing the basicity of amines.


36. Which of the following is the correct structure for dimethylamine?

a) CH3-NH-CH3
b) CH3-CH2-NH2
c) CH3-NH2
d) (CH3)2NH

Answer: d) (CH3)2NH
Explanation: Dimethylamine is represented by (CH3)2NH, where two methyl groups are attached to the nitrogen atom.


37. Which of the following is the product of the reaction of amines with formaldehyde?

a) Amides
b) Ureides
c) Schiff base
d) Hydrazones

Answer: c) Schiff base
Explanation: Amines react with formaldehyde to form Schiff bases (imines) through condensation reactions.


38. Which of the following amines can undergo Hofmann rearrangement?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: b) Methylamine
Explanation: Methylamine undergoes Hofmann rearrangement to produce methane.


39. Which of the following methods is used for the reduction of nitro compounds to amines?

a) Hydrogenation
b) Dehydrogenation
c) Nitration
d) Bromination

Answer: a) Hydrogenation
Explanation: Nitro compounds can be reduced to amines using hydrogenation (H2) over a suitable catalyst.


40. Which of the following amines is the most basic?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Tertiary amines

Answer: c) Dimethylamine
Explanation: Dimethylamine is the most basic due to the electron-donating effect of the two methyl groups.


41. Which of the following amines does not undergo the Hinsberg test?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: c) Dimethylamine
Explanation: Dimethylamine does not react with benzene sulfonyl chloride in the Hinsberg test, differentiating it from primary and secondary amines.


42. What is the nature of the bond between nitrogen and hydrogen in amines?

a) Polar covalent bond
b) Non-polar covalent bond
c) Ionic bond
d) Metallic bond

Answer: a) Polar covalent bond
Explanation: The bond between nitrogen and hydrogen in amines is a polar covalent bond due to the electronegativity difference between nitrogen and hydrogen.


43. Which of the following is a product of the reaction between an amine and an acid?

a) Alcohol
b) Ammonium salt
c) Ether
d) Alkene

Answer: b) Ammonium salt
Explanation: Amines react with acids to form ammonium salts, which are ionic compounds.


44. Which of the following amines is not aromatic?

a) Aniline
b) Benzydamine
c) Phenylamine
d) Methylamine

Answer: d) Methylamine
Explanation: Methylamine is an aliphatic amine, while the other options are aromatic amines.


45. Which of the following is used to synthesize secondary amines from primary amines?

a) Alkylation with an alkyl halide
b) Reduction with LiAlH4
c) Nitration with nitric acid
d) Dehydrohalogenation

Answer: a) Alkylation with an alkyl halide
Explanation: Secondary amines can be synthesized from primary amines through alkylation with alkyl halides.


46. Which of the following amines is used in the production of aspirin?

a) Methylamine
b) Aniline
c) Ethylamine
d) Dimethylamine

Answer: b) Aniline
Explanation: Aniline is used in the production of aspirin, which is synthesized from salicylic acid and acetic acid.


47. What is the major product of the reaction between an amine and an alkyl halide?

a) Alkylated amine
b) Ammonium salt
c) Amide
d) Alcohol

Answer: a) Alkylated amine
Explanation: Amines react with alkyl halides to form alkylated amines through nucleophilic substitution.


48. Which of the following amines is a common component of proteins?

a) Methylamine
b) Dimethylamine
c) Aniline
d) Amino acids

Answer: d) Amino acids
Explanation: Amino acids, which contain amine groups, are the building blocks of proteins.


49. Which of the following is a characteristic reaction of amines?

a) Reaction with carboxylic acids to form salts
b) Reaction with halogens to form halides
c) Reaction with metals to form oxides
d) Reaction with nitrous acid to form diazonium salts

Answer: d) Reaction with nitrous acid to form diazonium salts
Explanation: Aromatic amines react with nitrous acid to form diazonium salts, a characteristic reaction of amines.


50. Which of the following amines is most likely to undergo nucleophilic substitution with an alkyl halide?

a) Aniline
b) Methylamine
c) Dimethylamine
d) Ethylamine

Answer: b) Methylamine
Explanation: Methylamine, being a primary amine, is most likely to undergo nucleophilic substitution with alkyl halides to form secondary amines.