Q.1 Which of the following is a primary amine?
CH3NH2
CH3NHCH3
(CH3)3N
C6H5N(CH3)2
Explanation - A primary amine has one alkyl or aryl group attached to nitrogen. CH3NH2 has only one methyl group attached.
Correct answer is: CH3NH2
Q.2 What is the IUPAC name of CH3CH2NH2?
Ethylamine
Methylamine
Ethanamine
Dimethylamine
Explanation - The IUPAC name of CH3CH2NH2 is ethanamine, with the -amine group taking priority in nomenclature.
Correct answer is: Ethanamine
Q.3 Which reagent is used to distinguish primary, secondary, and tertiary amines?
Tollens' reagent
Bromine water
Hinsberg's reagent
Fehling's solution
Explanation - Hinsberg’s test uses benzenesulfonyl chloride to differentiate amines based on solubility of sulfonamide products.
Correct answer is: Hinsberg's reagent
Q.4 Which amine is most basic in aqueous solution?
NH3
CH3NH2
(CH3)2NH
(CH3)3N
Explanation - Secondary amines are usually more basic than primary and tertiary amines due to electron-donating alkyl groups and less steric hindrance.
Correct answer is: (CH3)2NH
Q.5 Which of the following is a tertiary amine?
CH3NH2
CH3CH2NH2
CH3N(CH3)2
C2H5NHCH3
Explanation - A tertiary amine has three alkyl/aryl groups attached to nitrogen; CH3N(CH3)2 fits this definition.
Correct answer is: CH3N(CH3)2
Q.6 Which of the following amines reacts with nitrous acid to form a diazonium salt?
Primary aromatic amine
Primary aliphatic amine
Secondary aromatic amine
Tertiary aliphatic amine
Explanation - Only primary aromatic amines form stable diazonium salts on reaction with nitrous acid at 0–5°C.
Correct answer is: Primary aromatic amine
Q.7 Which method is used for industrial preparation of aniline?
Gabriel phthalimide synthesis
Reduction of nitrobenzene
Hofmann bromamide reaction
Curtius rearrangement
Explanation - Aniline is mainly prepared industrially by catalytic hydrogenation or reduction of nitrobenzene.
Correct answer is: Reduction of nitrobenzene
Q.8 What is the product of CH3NH2 with acetyl chloride?
CH3NHCOCH3
CH3NCOCH3
CH3NH2
CH3COCH3
Explanation - Acetylation of primary amine gives an N-substituted amide. CH3NH2 + CH3COCl → CH3NHCOCH3.
Correct answer is: CH3NHCOCH3
Q.9 Which of the following amines is aromatic?
CH3NH2
C6H5NH2
CH3CH2NH2
(CH3)3N
Explanation - An aromatic amine has nitrogen directly attached to an aromatic ring. C6H5NH2 (aniline) qualifies.
Correct answer is: C6H5NH2
Q.10 Which reagent is used in the Hofmann bromamide reaction?
Br2/NaOH
HNO2
SOCl2
NaBH4
Explanation - Hofmann bromamide reaction converts amides to primary amines using bromine and alkali (NaOH).
Correct answer is: Br2/NaOH
Q.11 Which of the following amines will give a positive Hinsberg test but is soluble in alkali?
Primary amine
Secondary amine
Tertiary amine
Quaternary ammonium salt
Explanation - Primary amines react with Hinsberg’s reagent to give soluble sulfonamides in alkali, unlike secondary amines.
Correct answer is: Primary amine
Q.12 Which is the least basic among the following?
CH3NH2
C6H5NH2
(CH3)2NH
(C2H5)3N
Explanation - Aniline is less basic due to delocalization of lone pair electrons into the benzene ring.
Correct answer is: C6H5NH2
Q.13 Which amine reacts with nitrous acid to produce alcohol?
Primary aliphatic amine
Primary aromatic amine
Secondary amine
Tertiary amine
Explanation - Primary aliphatic amines react with nitrous acid to form unstable diazonium ions, which decompose to alcohols.
Correct answer is: Primary aliphatic amine
Q.14 Which reaction is used to prepare primary amines from alkyl halides?
Gabriel phthalimide synthesis
Hofmann degradation
Curtius rearrangement
Eschweiler-Clarke reaction
Explanation - Gabriel synthesis converts primary alkyl halides to primary amines without forming secondary or tertiary amines.
Correct answer is: Gabriel phthalimide synthesis
Q.15 Which of the following is a secondary amine?
CH3NH2
CH3NHCH3
CH3N(CH3)2
NH3
Explanation - Secondary amines have two alkyl/aryl groups attached to nitrogen. CH3NHCH3 is secondary.
Correct answer is: CH3NHCH3
Q.16 Which of the following is true about quaternary ammonium salts?
They are basic
They do not have N-H bonds
They react with Hinsberg’s reagent
They are primary amines
Explanation - Quaternary ammonium salts have four alkyl groups on nitrogen, so no N-H bond exists.
Correct answer is: They do not have N-H bonds
Q.17 Which amine is most nucleophilic?
CH3NH2
CH3CH2NH2
(CH3)3N
C6H5NH2
Explanation - Aliphatic primary amines are more nucleophilic than aromatic amines due to availability of lone pair electrons.
Correct answer is: CH3CH2NH2
Q.18 Which of the following amines is less soluble in water?
CH3NH2
C6H5NH2
CH3CH2NH2
NH3
Explanation - Aniline is less soluble due to the hydrophobic benzene ring despite having an -NH2 group.
Correct answer is: C6H5NH2
Q.19 What is the major product when CH3NH2 reacts with CH3COCl?
CH3NHCOCH3
CH3NCOCH3
CH3CONHCH3
CH3CH2NH2
Explanation - Acylation of primary amine produces N-substituted amide as the major product.
Correct answer is: CH3NHCOCH3
Q.20 Which amine is least sterically hindered?
CH3NH2
CH3CH2NH2
(CH3)2NH
(CH3)3N
Explanation - CH3NH2 is a primary amine with the smallest substituent, thus least steric hindrance.
Correct answer is: CH3NH2
Q.21 Which of the following amines gives a blue precipitate with nitrous acid in cold condition?
Primary aromatic amine
Primary aliphatic amine
Secondary amine
Tertiary amine
Explanation - Secondary amines react with nitrous acid to form N-nitrosoamines, often giving a colored precipitate.
Correct answer is: Secondary amine
Q.22 Which reaction involves conversion of primary amide to primary amine?
Hofmann bromamide reaction
Gabriel phthalimide synthesis
Curtius rearrangement
Eschweiler-Clarke reaction
Explanation - Hofmann bromamide reaction converts primary amides to primary amines with one fewer carbon atom.
Correct answer is: Hofmann bromamide reaction
Q.23 Which reagent converts primary and secondary amines to N-methyl derivatives?
Formaldehyde and H2/Pd
Formaldehyde and NaBH3CN
CH3I alone
Acetic anhydride
Explanation - Eschweiler-Clarke reaction methylates primary and secondary amines using formaldehyde and NaBH3CN.
Correct answer is: Formaldehyde and NaBH3CN
Q.24 Which type of amine reacts fastest with benzene sulfonyl chloride?
Primary
Secondary
Tertiary
Quaternary ammonium
Explanation - Primary amines react fastest with benzene sulfonyl chloride to give soluble sulfonamides.
Correct answer is: Primary