Chemistry · Textbook solutions

Amines

Every solved example, exercise, and miscellaneous question — in the order the textbook teaches them. · 40 questions

13. Amines — worked examples

2 q

Solved Examples

Worked · 2
  1. Solved Ex.13.1
    Write reaction to convert methyl bromide into ethyl amine ? Also, comment on the number of carbon atoms in the starting compound and the product.
  2. Solved Ex.13.1b
    Write the scheme for preparation of p-bromoaniline from aniline. Justify your answer.

Exercises

38 q

1. Choose the most correct option

Practice · 10
  1. Choose the most correct option.
    Ex Q.1 (i)
    The hybridisation of nitrogen in primary amine is ............
    1. A.
      spsp
    2. B.
      sp2sp^2
    3. C.
      sp3sp^3
    4. D.
      sp3dsp^3d
  2. Ex Q.1 (ii)
    Isobutylamine is an example of ............
    1. A.
      2∘2^\circ amine
    2. B.
      3∘3^\circ amine
    3. C.
      1∘1^\circ amine
    4. D.
      quaternary ammonium salt.
  3. Ex Q.1 (iii)
    Which one of the following compounds has the highest boiling point ?
    1. A.
      n-Butylamine
    2. B.
      sec-Butylamine
    3. C.
      isobutylamine
    4. D.
      tert-Butylamine
  4. Ex Q.1 (iv)
    Which of the following has the highest basic strength ?
    1. A.
      Trimethylamine
    2. B.
      Methylamine
    3. C.
      Ammonia
    4. D.
      Dimethylamine
  5. Ex Q.1 (v)
    Which type of amine does produce N2\mathrm{N_2} when treated with HNO2\mathrm{HNO_2} ?
    1. A.
      Primary amine
    2. B.
      Secondary amine
    3. C.
      Tertiary amine
    4. D.
      Both primary and secondary amines
  6. Ex Q.1 (vi)
    Carbylamine test is given by
    1. A.
      Primary amine
    2. B.
      Secondary amine
    3. C.
      Tertiary amine
    4. D.
      Both secondary and tertiary amines
  7. Ex Q.1 (vii)
    Which one of the following compounds does not react with acetyl chloride ?
    1. A.
      CH3−CH2−NH2\mathrm{CH_3-CH_2-NH_2}
    2. B.
      (CH3−CH2)2NH\mathrm{(CH_3-CH_2)_2NH}
    3. C.
      (CH3−CH2)3N\mathrm{(CH_3-CH_2)_3N}
    4. D.
      C6H5−NH2\mathrm{C_6H_5-NH_2}
  8. Ex Q.1 (viii)
    Which of the following compounds will dissolve in aqueous NaOH after undergoing reaction with Hinsberg reagent ?
    1. A.
      Ethylamine
    2. B.
      Triethylamine
    3. C.
      Trimethylamine
    4. D.
      Diethylamine
  9. Ex Q.1 (ix)
    Identify 'B' in the following reactions CH3−C≡N→Na/C2H5OHA→NaNO2/dil HClB\mathrm{CH_3-C}\equiv\mathrm{N} \xrightarrow{\mathrm{Na/C_2H_5OH}} \mathrm{A} \xrightarrow{\mathrm{NaNO_2/dil\ HCl}} \mathrm{B}
    1. A.
      CH3−CH2−NH2\mathrm{CH_3-CH_2-NH_2}
    2. B.
      CH3−CH2−NO2\mathrm{CH_3-CH_2-NO_2}
    3. C.
      CH3−CH2N2⊕Cl⊖\mathrm{CH_3-CH_2N_2^{\oplus}Cl^{\ominus}}
    4. D.
      CH3−CH2−OH\mathrm{CH_3-CH_2-OH}
  10. Ex Q.1 (x)
    Which one of the following compounds contains azo linkage ?
    1. A.
      Hydrazine
    2. B.
      p-Hydroxyazobenzene
    3. C.
      N-Nitrosodiethylamine
    4. D.
      Ethylenediamine

2. Answer in one sentence

Practice · 10
  1. Answer in one sentence.
    Ex Q.2 (i)
    Write reaction of p-toluenesulfonyl chloride with diethylamine.
  2. Ex Q.2 (ii)
    How many moles of methylbromide are required to convert ethanamine to N, N-dimethyl ethanamine ?
  3. Ex Q.2 (iii)
    Which amide does produce ethanamine by Hofmann bromamide degradation reaction?
  4. Ex Q.2 (iv)
    Write the order of basicity of aliphatic alkylamine in gaseous phase.
  5. Ex Q.2 (v)
    Why are primary aliphatic amines stronger bases than ammonia ?
  6. Ex Q.2 (vi)
    Predict the product of the following reaction. Nitrobenzene →Sn/Conc. HCl\xrightarrow{\text{Sn/Conc. HCl}} ?
  7. Ex Q.2 (vii)
    Write the IUPAC name of benzylamine.
  8. Ex Q.2 (viii)
    Arrange the following amines in an increasing order of boiling points. n-propylamine, ethylmethyl amine, trimethylamine.
  9. Ex Q.2 (ix)
    Write the balanced chemical equations for the action of dil H2SO4\mathrm{H_2SO_4} on diethylamine.
  10. Ex Q.2 (x)
    Arrange the following amines in the increasing order of their pKb\mathrm{pK_b} values. Aniline, Cyclohexylamine, 4-Nitroaniline

3. Answer the following

Practice · 11
  1. Answer the following
    Ex Q.3 (i)
    Identify A and B in the following reactions. C6H5CH2Br→KCNalco.A→Na/ethanolB\mathrm{C_6H_5CH_2Br} \xrightarrow[\mathrm{KCN}]{\text{alco.}} \mathrm{A} \xrightarrow{\text{Na/ethanol}} \mathrm{B}.
  2. Ex Q.3 (ii)
    Explain the basic nature of amines with suitable example.
  3. Ex Q.3 (iii)
    What is diazotisation ? Write diazotisation reaction of aniline.
  4. Ex Q.3 (iv)
    Write reaction to convert acetic acid into methylamine.
  5. Ex Q.3 (v)
    Write a short note on coupling reactions.
  6. Ex Q.3 (vi)
    Explain Gabriel phthalimide synthesis.
  7. Ex Q.3 (vii)
    Explain carbylamine reaction with suitable examples.
  8. Ex Q.3 (viii)
    Write reaction to convert (i) methanamine into ethanamine (ii) Aniline into p-bromoaniline.
  9. Ex Q.3 (ix)
    Complete the following reactions : a. C6H5N2⊕Cl⊖+C2H5OH⟶\mathrm{C_6H_5N_2^{\oplus}Cl^{\ominus}} + \mathrm{C_2H_5OH} \longrightarrow b. C6H5NH2+Br2(aq)⟶\mathrm{C_6H_5NH_2} + \mathrm{Br_2(aq)} \longrightarrow ?
  10. Ex Q.3 (x)
    Explain Ammonolysis of alkyl halides.
  11. Ex Q.3 (xi)
    Write reaction to convert ethylamine into methylamine.

4. Answer the following

Practice · 7
  1. Answer the following.
    Ex Q.4 (i)
    Write the IUPAC names of the following amines : a. CH3−CH2−N(CH3)−CH2−CH2−CH3\mathrm{CH_3-CH_2-N(CH_3)-CH_2-CH_2-CH_3} b. CH3−C(CH3)2−CH2−CH2−NH2\mathrm{CH_3-C(CH_3)_2-CH_2-CH_2-NH_2} c. CH3−CH(CH3)−NH−CH2−CH3\mathrm{CH_3-CH(CH_3)-NH-CH_2-CH_3}
  2. Ex Q.4 (ii)
    What are amines ? How are they classified ?
  3. Ex Q.4 (iii)
    Write IUPAC names of the following amines. a. H2N−(CH2)6−NH2\mathrm{H_2N-(CH_2)_6-NH_2} b. and c. are shown in the figure.
  4. Ex Q.4 (iv)
    Write reactions to prepare ethanamine from a. Acetonitrile b. Nitroethane c. Propionamide
  5. Ex Q.4 (v)
    What is the action of acetic anhydride on ethylamine, diethylamine and triethylamine ?
  6. Ex Q.4 (vii)
    Distinguish between ethylamine, diethylamine and triethylamine by using Hinsberg's reagent ?
  7. Ex Q.4 (viii)
    Write reactions to bring about the following conversions : a. Aniline into p-nitroaniline b. Aniline into sulphanilic acid ?