Aromatic Amines: Aniline & Derivatives — Practice Questions

Free NEET Chemistry multiple-choice questions on Aromatic Amines: Aniline & Derivatives. Attempt each question and reveal the answer with a full explanation.

What is the product 'X' in the reaction: Aniline Ac 2O/Pyridine X ? Acetanilide N-methylaniline Benzanilide p-aminoacetophenone What is the product 'B' in the following reaction sequence: C 6H 5NO 2 Sn/HCl A Ac 2O B ? Acetanilide Aniline Benzanilide p -Nitroacetanilide Reduction of nitrobenzene with SnCl 2/HCl gives: Aniline Phenylhydroxylamine Nitrosobenzene Hydrazobenzene Which of the following will not form a Zwitterion? Aniline Sulphanilic acid Glycine Anthranilic acid Compared to cyclohexylamine, aniline is significantly less basic because: The lone pair on Nitrogen in aniline is delocalized into the benzene ring. Aniline has a higher molecular weight. The Nitrogen in aniline is sp 2 hybridized. Cyclohexylamine has more steric hindrance. Which of the following reagents is used in the Schotten-Baumann reaction of aniline? Benzoyl chloride and aqueous NaOH Acetyl chloride and Pyridine Benzenesulphonyl chloride and KOH Methyl iodide and Ag 2O Aniline reacts with hydrogen in the presence of a Nickel catalyst at 473 K and high pressure to form: Cyclohexylamine Benzene Cyclohexane n -Hexylamine Aniline is soluble in aqueous HCl but insoluble in aqueous NaOH because: It forms a soluble salt with HCl but is too weak an acid to react with NaOH . It is a strong base and reacts with NaOH to form a precipitate. The -NH 2 group is hydrophobic. Aniline is a non-polar organic liquid. Which of the following will be most stable diazonium salt RN2 +X - ? CH3N2 +X - C6H5N2 +X - CH3CH2N2 +X - C6H5CH2N2 +X - The reaction : ArN2Cl ->[Cu/HCl] ArCl + N2 is known as Balz Schiemann reaction Sandmeyers reaction Finkelstein reaction Gattermann reaction The reagent 'R' in the given sequence of chemical reaction is: CH3CH2OH HI CuCN/KCN H2O Nitration of aniline is usually performed by protecting the -NH 2 group through: Acetylation Methylation Sulphonation Reduction Given below are two statements Statement I: Primary aliphatic amines react with HNO2 to give unstable diazonium salts. Statement II: Primary aromatic amines react with HNO2 to form diazonium salts which are stable even above 300 K. In the light of the above statements, choose the most appropriate answer from the options given below Both Statement I and Statement II are incorrect. Statement I is correct but Statement II is incorrect. Statement I is incorrect but Statement II is correct. Both Statement I and Statement II are correct. Given below are two statements : Statement-I : Benzenediazonium salt is prepared by the reaction of aniline with nitrous acid at 273 – 278 K. It decomposes easily in the dry state. Statement-II : Insertion of iodine into the benzene ring is difficult and hence iodobenzene is prepared through the reaction of benzenediazonium salt with KI. In the light of the above statements, choose the most appropriate answer from the options given below : Statement I is incorrect but Statement II is correct Both Statement I and Statement II are correct Both Statement I and Statement II are incorrect Statement I is correct but Statement II is incorrect The correct order of increasing basic strength for the following aniline derivatives is: p-Nitroaniline < Aniline < p-Toluidine Aniline < p-Nitroaniline < p-Toluidine p-Toluidine < Aniline < p-Nitroaniline Aniline < p-Toluidine < p-Nitroaniline Aniline reacts with excess of methyl iodide to give a final product which is: (C 6H 5N(CH 3) 3) +I - C 6H 5NHCH 3 C 6H 5N(CH 3) 2 None of these Which of the following statements about the basicity of amines is FALSE? Aromatic amines are more basic than aliphatic amines. Basicity of amines is due to the presence of a lone pair on Nitrogen. Alkyl groups increase basicity of aliphatic amines in the gas phase. Electron withdrawing groups decrease the basicity of aniline. Reduction of Nitrobenzene with Zn/NH 4Cl gives: Phenylhydroxylamine Aniline Azobenzene Hydrazobenzene The reaction C 6H 5NH 2 + CH 3COCl Base C 6H 5NHCOCH 3 + HCl is an example of: Nucleophilic acyl substitution Electrophilic substitution Free radical reaction Electrophilic addition Comparing the basicity of Benzylamine ( C 6H 5CH 2NH 2 ) and Aniline ( C 6H 5NH 2 ), which statement is true? Benzylamine is more basic because the lone pair on N is not delocalized. Aniline is more basic because of the +R effect of the phenyl group. Benzylamine is less basic due to the -I effect of the phenyl group. Both have equal basicity as both are primary amines. Nitration of acetanilide followed by hydrolysis yields p -nitroaniline as the major product. The purpose of acetylating aniline first is to: Decrease the activating effect of the -NH 2 group to prevent polysubstitution. Increase the reactivity of the ring towards electrophilic attack. Protect the ring from oxidation by nitric acid. Make the -NH 2 group meta-directing. Oxidation of aniline with acidified potassium dichromate ( K 2Cr 2O 7/H 2SO 4 ) results in the formation of: p -Benzoquinone Nitrobenzene Azobenzene Benzidine Aniline is separated from a mixture of aniline and nitrobenzene by: Steam distillation Fractional distillation Vacuum distillation Sublimation Which of the following compounds will have the highest pK b value? p -Nitroaniline p -Methoxyaniline Aniline p -Toluidine The major product formed when aniline reacts with Br 2 in glacial acetic acid is: p -bromoaniline 2,4,6 -tribromoaniline o -bromoaniline m -bromoaniline Which of the following has the lowest basicity due to the 'Ortho Effect'? o -Toluidine m -Toluidine p -Toluidine Aniline Reduction of nitrobenzene with Zn and NH 4Cl in aqueous ethanol gives: Phenylhydroxylamine Aniline Azobenzene Hydrazobenzene Among the following, which one has the highest dipole moment? p -Nitroaniline m -Nitroaniline o -Nitroaniline Nitrobenzene The correct order of basic strength of the following in aqueous medium is: Benzylamine > Aniline > p -Nitroaniline Aniline > Benzylamine > p -Nitroaniline p -Nitroaniline > Aniline > Benzylamine Benzylamine > p -Nitroaniline > Aniline When nitrobenzene is treated with fuming nitric acid and concentrated H 2SO 4 at 100 C , the major product is: m -Dinitrobenzene o -Dinitrobenzene p -Dinitrobenzene 1,3,5-Trinitrobenzene Which of the following statements is true regarding the basicity of Pyrrole? It is extremely weakly basic because the lone pair on N is part of the aromatic sextet. It is more basic than aniline. It is a strong base like aliphatic amines. It is basic due to the presence of two double bonds. The pK b of Aniline is 9.4. What is the pK b of p -Methylaniline (p-toluidine) approximately? 8.9 9.4 10.2 13.0 The major product of the reaction between p -toluidine and Br 2/H 2O is: 2,6 -Dibromo- 4 -methylaniline 2 -Bromo- 4 -methylaniline 3 -Bromo- 4 -methylaniline 2,4,6 -Tribromoaniline Aniline is more reactive than benzene towards electrophilic substitution because of: +R effect of -NH 2 group -I effect of -NH 2 group +I effect of -NH 2 group Hyperconjugation What is the correct order of basic strength for the following compounds: (I) Benzylamine, (II) Aniline, (III) m -Nitroaniline? I > II > III III > II > I II > I > III I > III > II Aniline on reaction with fuming sulphuric acid at 180 C gives: Sulphanilic acid Orthanilic acid Aniline hydrogen sulphate Benzene sulphonic acid Which of the following describes the correct order of the pK b values for the given amines: (I) Aniline, (II) p -Nitroaniline, (III) p -Methoxyaniline? (II) > (I) > (III) (III) > (I) > (II) (I) > (II) > (III) (II) > (III) > (I) The reaction of aniline with a mixture of concentrated HNO 3 and H 2SO 4 without protecting the amino group yields a mixture of products. Which of the following is NOT a major component of this mixture? o -Nitroaniline p -Nitroaniline m -Nitroaniline Anilinium sulphate During the acetylation of aniline to form acetanilide, pyridine is often added. What is the role of pyridine? To remove the HCl formed and shift the equilibrium to the right. To act as a catalyst for the nucleophilic attack. To prevent the oxidation of aniline. To increase the solubility of aniline in water. Primary amines react with benzaldehyde to form 'Schiff bases'. Schiff bases are also known as: Anils Oximes Hydrazones Nitriles When aniline is treated with bromine in the presence of CS 2 at low temperature, the major product is: p -Bromoaniline 2,4,6 -Tribromoaniline o -Bromoaniline m -Bromoaniline The correct decreasing order of basic strength for the following p-substituted anilines is: (I) p -anisidine, (II) p -toluidine, (III) p -chloroaniline, (IV) p -nitroaniline. I > II > III > IV IV > III > II > I II > I > III > IV I > II > IV > III The explosive 'Tetryl' is chemically known as: N -Methyl- N,2,4,6 -tetranitroaniline 2,4,6 -Trinitrotoluene 1,3,5 -Trinitrobenzene Glycerol trinitrate The reaction of Nitrobenzene with NaBH 4 in methanol results in: No reaction Aniline Phenylhydroxylamine Azobenzene Identify the product 'B' in the sequence: Nitrobenzene Fe/HCl A Br 2(aq) B 2,4,6-Tribromoaniline p-Bromoaniline o-Bromoaniline m-Bromoaniline Which of the following methods cannot be used for the preparation of aniline? Gabriel Phthalimide Synthesis Reduction of nitrobenzene with Sn/HCl Hofmann bromamide degradation of benzamide Reduction of benzonitrile with LiAlH 4 When aniline is treated with concentrated H 2SO 4 and concentrated HNO 3 at 288 K , a significant amount of m-nitroaniline is formed. This is due to: Protonation of aniline to form anilinium ion which is meta-directing Deactivation of the ring by the nitro group Steric hindrance at ortho and para positions The reaction being carried out at a very high temperature Aniline does not undergo Friedel-Crafts reaction because: The AlCl 3 catalyst forms a salt with the amino group The amino group is meta-directing Aniline is too volatile The benzene ring is deactivated by the lone pair of Nitrogen The product of the reaction between Aniline and Benzoyl chloride in the presence of NaOH is: Benzanilide N-methylaniline Acetanilide Azobenzene In the reaction A is HgSO4/H2SO4 Cu2Cl2 H3PO2 and H2O H+/H2O In the following reaction, the product (A) is :- The product formed from the following reaction sequence is Identify the product in the following reaction: The reaction of an amine with Sanger's reagent (1-fluoro-2,4-dinitrobenzene) is an example of: Nucleophilic aromatic substitution Electrophilic aromatic substitution Nucleophilic addition Free radical substitution Reduction of nitrobenzene with LiAlH 4 in ether gives: Azobenzene Aniline Phenylhydroxylamine Hydrazobenzene When aniline reacts with benzaldehyde, the product formed is known as: Schiff's base Enamine Glycosylamine Amidine Which of the following is the correct decreasing order of basic strength for the given compounds: (I) Aniline, (II) o -Toluidine, (III) m -Toluidine, (IV) p -Toluidine? IV > III > I > II IV > I > III > II II > IV > III > I I > II > III > IV Which of the following reaction sequences is most suitable to convert Nitrobenzene to p -Bromoaniline? Sn/HCl , then Ac 2O , then Br 2/Fe , then H 3O + Br 2/Fe , then Sn/HCl Sn/HCl , then Br 2(aq) H 2/Pd , then Br 2/CH 3COOH The correct order of increasing basic strength of the following compounds: (I) Aniline, (II) o -Nitroaniline, (III) m -Nitroaniline, (IV) p -Nitroaniline is: (II) < (IV) < (III) < (I) (II) < (III) < (IV) < (I) (IV) < (II) < (III) < (I) (I) < (III) < (IV) < (II) What is the order of the C-N bond length in the following: (I) Methylamine, (II) Aniline, (III) Acetamide? (I) > (II) > (III) (III) > (II) > (I) (II) > (I) > (III) (I) > (III) > (II) When aniline is converted to anilinium ion by the addition of a strong acid, the max in its UV spectrum shifts towards a shorter wavelength. This phenomenon is known as: Blue shift (Hypsochromic shift) Red shift (Bathochromic shift) Hyperchromic shift Hypochromic shift The resonance energy of aniline is approximately 151 kJ/mol , while that of benzene is 152 kJ/mol . The slightly lower value for aniline compared to benzene is due to: The resonance hybrid involving charge separation The +I effect of the -NH 2 group The electronegativity of Nitrogen being higher than Carbon Steric hindrance of the amino group Nitration of m -nitroaniline with concentrated HNO 3/H 2SO 4 yields which major product? 1,3,5 -Trinitrobenzene 2,4 -Dinitroaniline 1,2,4 -Trinitrobenzene m -Dinitrobenzene Identify the reactions which give aniline as the major product. Choose the correct answer from the options given below. A and B only B and D only A and C only C and D only Aniline reacts with concentrated H 2SO 4 at room temperature to form a salt. What is the name of this salt? Anilinuim hydrogensulphate Sulphanilic acid Sulphanylamide Aniline sulphate The product formed when aniline reacts with bromine water is: 2,4,6-tribromoaniline 2-bromoaniline 4-bromoaniline 3,5-dibromoaniline In the nitration of acetanilide, the -NHCOCH 3 group acts as a/an: Ortho/Para directing and activating group Meta directing and deactivating group Ortho/Para directing and deactivating group Meta directing and activating group