12th Chemistry - Book Back Answers - Unit 13 Organic Nitrogen Compounds - English Medium Guides

  

 

Plus Two / 12th Chemistry - Book Back Answers - Unit 13 - English Medium

Tamil Nadu Board 12th Standard Chemistry - Unit 13: Book Back Answers and Solutions

    This post covers the book back answers and solutions for Unit 13 from the Tamil Nadu State Board 12th Standard Chemistry textbook. These detailed answers have been carefully prepared by our expert teachers at KalviTips.com.

    We have explained each answer in a simple, easy-to-understand format, highlighting important points step by step under the relevant subtopics. Students are advised to read and memorize these subtopics thoroughly. Once you understand the main concepts, you’ll be able to connect other related points with real-life examples and confidently present them in your tests and exams.

    By going through this material, you’ll gain a strong understanding of Unit 13 along with the corresponding book back questions and answers (PDF format).

Question Types Covered:

• 1 Mark Questions: Choose the correct answer, Fill in the blanks, Identify the correct statement, Match the following 
• 2 Mark Questions: Answer briefly 
• 3, 4, and 5 Mark Questions: Answer in detail

All answers are presented in a clear and student-friendly manner, focusing on key points to help you score full marks.

All the best, Class 12 students! Prepare well and aim for top scores. Thank you!

Unit 13 - Organic Nitrogen Compounds

I. Multiple Choice Questions

1. Which of the following reagent can be used to convert nitrobenzene to aniline

a) Sn / HCl

b) ZnHg / NaOH

c) Zn/NH₄Cl

d) All of these

Answer Key:

a) Sn / HCl 

  

2. The method by which aniline cannot be prepared is

a) degradation of benzamide with Br₂ / NaOH

b) potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with aqueous NaOH solution.

c) reduction of NitrNobi e(onrz)e nPet, w(oitrh) LiAlH₄

d) reduction of nitrobenzene by Sn / HCl.

Answer Key:

b) potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with aqueous NaOH solution.

  

3. Which one of the following will not undergo Hofmann bromamide reaction

a) CH₃CONHCH₃

b) CH₃CH₂CONH₂

c) CH₃CONH₂

d) C₆H₅CONH₂

Answer Key:

a) CH₃CONHCH₃

  

4. Assertion : Acetamide on reaction with KOH and bromine gives acetic acid

Reason : Bromine catalyses hydrolysis of acetamide.

a) if both assertion and reason are true and reason is the correct explanation of assertion.

b) if both assertion and reason are true but reason is not the correct explanation of

assertion.

c) assertion is true but reason is false

d) both assertion and reason are false.

Answer Key:

d) both assertion and reason are false. 

 

5. $\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{C}{\mathbf{H}}_{\mathbf{2}}\mathbf{B}\mathbf{r}\underset{\mathbf{△}}{\overset{\mathbf{a}\mathbf{q}\mathbf{ }\mathbf{N}\mathbf{a}\mathbf{O}\mathbf{H}}{\mathbf{\to }}}\mathbf{A}\underset{\mathbf{△}}{\overset{\mathbf{K}\mathbf{M}\mathbf{n}{\mathbf{O}}_{\mathbf{4}}}{\mathbf{\to }}}\mathbf{B}\underset{\mathbf{△}}{\overset{\mathbf{N}{\mathbf{H}}_{\mathbf{3}}}{\mathbf{\to }}}\mathbf{C}\stackrel{\mathbf{B}{\mathbf{r}}_{\mathbf{2}}\mathbf{/}\mathbf{N}\mathbf{a}\mathbf{O}\mathbf{H}}{\mathbf{\to }}\mathbf{D}$ ‘D’ is

a) bromomethane

b) $\mathbf{\alpha }$_ - bromo sodium acetate

c) methanamine

d) acetamide

Answer Key:

c) methanamine

  

6. Which one of the following nitro compounds does not react with nitrous acid

a) CH₃-CH₂-CH₂-NO₂

b) (CH₃)₂CH-CH₂NO₂

c) (CH₃)₃C NO₂

d) $\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{-}\underset{\underset{\mathbf{O}}{\mathbf{\left|}\mathbf{\right|}}}{\mathbf{C}}\mathbf{-}\underset{\underset{\mathbf{C}{\mathbf{H}}_{\mathbf{3}}}{\mathbf{|}}}{\mathbf{C}\mathbf{H}}\mathbf{-}\mathbf{N}{\mathbf{O}}_{\mathbf{2}}$

Answer Key:

c) (CH₃)₃C NO₂

  

7. Aniline + benzoylchloride $\stackrel{\mathbf{N}\mathbf{a}\mathbf{O}\mathbf{H}}{\mathbf{\to }}{\mathbf{C}}_{\mathbf{6}}{\mathbf{H}}_{\mathbf{5}}\mathbf{-}\mathbf{N}\mathbf{H}\mathbf{-}\mathbf{C}\mathbf{O}{\mathbf{C}}_{\mathbf{6}}{\mathbf{H}}_{\mathbf{5}}$

this reaction is known as

a) Friedel – crafts reaction

b) HVZ reaction

c) Schotten – Baumann reaction

d) none of these

Answer Key:

c) Schotten – Baumann reaction 

  

8. The product formed by the reaction an aldehyde with a primary amine (NEET)

a) carboxylic acid

b) aromatic acid

c) schiff ’s base

d) ketone

Answer Key:

c) schiff ’s base

  

9. Which of the following reaction is not correct.

a) $\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{C}{\mathbf{H}}_{\mathbf{2}}\mathbf{N}{\mathbf{H}}_{\mathbf{2}}\stackrel{\mathbf{H}\mathbf{N}{\mathbf{O}}_{\mathbf{2}}}{\mathbf{\to }}\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{C}{\mathbf{H}}_{\mathbf{2}}\mathbf{O}\mathbf{H}\mathbf{+}{\mathbf{N}}_{\mathbf{2}}$

b) 

c) $\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{C}\mathbf{O}\mathbf{N}{\mathbf{H}}_{\mathbf{2}}\stackrel{\mathbf{B}{\mathbf{r}}_{\mathbf{2}}\mathbf{/}\mathbf{N}\mathbf{a}\mathbf{O}\mathbf{H}}{\to }\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{N}{\mathbf{H}}_{\mathbf{2}}$

d) none of these

Answer Key:

10. When aniline reacts with acetic anhydride the product formed is

a) o – aminoacetophenone

b) m-aminoacetophenone

c) p – aminoacetophenone

d) acetanilide

Answer Key:

d) acetanilide

  

11. The order of basic strength for methyl substituted amines in aqueous solution is

a) N(CH₃) > N(CH₃)₂H > N(CH₃)H ₂> NH₃

b) N(CH₃)H₂ > N(CH₃)₂H > N(CH₃)₃ >NH ₃

c) NH ₃>N(CH₃)H ₂> N(CH₃)₂H> N(CH₃)₃

d) N(CH₃)₂H > N(CH₃)H₂> N(CH₃)₃> NH₃

Answer Key:

d) N(CH₃)₂H > N(CH₃)H₂> N(CH₃)₃> NH₃

  

12. 

a) H₃PO₂ and H₂O

b) H⁺ / H₂O

c) HgSO₄ / H₂SO₄

d) Cu₂Cl₂

Answer Key:

d) Cu₂Cl₂

  

13. ${\mathbf{C}}_{\mathbf{6}}{\mathbf{H}}_{\mathbf{5}}\mathbf{N}{\mathbf{O}}_{\mathbf{2}}\stackrel{\mathbf{F}\mathbf{e}\mathbf{/}\mathbf{H}\mathbf{C}\mathbf{l}}{\mathbf{\to }}\mathbf{A}\underset{\mathbf{273}\mathbf{K}}{\overset{\mathbf{N}\mathbf{a}\mathbf{N}{\mathbf{O}}_{\mathbf{2}}\mathbf{/}\mathbf{H}\mathbf{C}\mathbf{l}}{\mathbf{\to }}}\mathbf{B}\underset{\mathbf{283}\mathbf{K}}{\overset{{\mathbf{H}}_{\mathbf{2}}\mathbf{O}}{\mathbf{\to }}}\mathbf{C}$ ‘C’ is

a) C₆H₅ - OH

b) C₆H₅ – CH₂OH

c) C₆H₅ - CHO

d) C₆H₅ NH₂

Answer Key:

a) C₆H₅ - OH 

  

14. Nitrobenzene on reaction with Con HNO₃ / H2_SO₄ at 80-100oC forms which one of the following products?

a) 1,4 – dinitrobenzene

b) 2,4,6 – tirnitrobenzene

c) 1,2 – dinitrobenzene

d) 1,3 – dinitrobenzene

Answer Key:

d) 1,3 – dinitrobenzene

  

15. C₅H₁₃N reacts with HNO₂ to give an optically active compound – The compound is

a) pentan – 1- amine

b) pentan – 2- amine

c) N,N – dimethylpropan -2-amine

d) diethyl methyl amine

Answer Key:

b) pentan – 2- amine

  

16. Secondary nitro alkanes react with nitrous acid to form

a) red solution

b) blue solution

c) green solution

d) yellow solution

Answer Key:

b) blue solution

  

17. Which of the following amines does not undergo acetylation?

a) t – butylamine

b) ethylamine

c) diethylamine

d) triethylamine

Answer Key:

d) triethylamine

  

18. Which one of the following is most basic?

a) 2,4 – dichloroaniline

b) 2,4 – dimethyl aniline

c) 2,4 – dinitroaniline

d) 2,4 – dibromoaniline

Answer Key:

b) 2,4 – dimethyl aniline

  

19. When

  is reduced with Sn / HCl the pair of compounds formed are

a) Ethanol, hydroxylamine hydrochloride

b) Ethanol, ammonium hydroxide

c) Ethanol, NH₂OH

d) C₃H₅NH2, H2O

Answer Key:

a) Ethanol, hydroxylamine hydrochloride 

  

20. IUPAC name for the amine

$\mathbf{C}{\mathbf{H}}_{\mathbf{3}}\mathbf{-}\underset{\underset{\mathbf{C}{\mathbf{H}}_{\mathbf{3}}}{\mathbf{|}}}{\mathbf{N}}\mathbf{-}\underset{\underset{{\mathbf{C}}_{\mathbf{2}}{\mathbf{H}}_{\mathbf{5}}}{\mathbf{|}}}{\overset{\stackrel{{\mathbf{CH}}_{\mathbf{3}}}{\mathbf{|}}}{\mathbf{C}}}\mathbf{-}\mathbf{C}{\mathbf{H}}_{\mathbf{2}}\mathbf{-}{\mathbf{CH}}_{\mathbf{3}}$ is

a) 3 – Bimethylamino – 3 – methyl pentane

b) 3 (N,N – Triethyl) – 3- amino pentane

c) 3 – N,N – trimethyl pentanamine

d) N,N – dimethyl – 3- methyl - pentan - 3 amine

Answer Key:

d) N,N – dimethyl – 3- methyl - pentan - 3 amine

  

21. 

 P Product ‘P’ in the above reaction is

a) 

b) 

c) 

d) 

Answer Key:

 

22. Ammonium salt of benzoic acid is heated strongly with P₂O₅ and the product so formed is reduced and then treated with NaNO₂/ HCl  at low temperature. The final compound formed is

a) Benzene diazonium chloride

b) Benzyl alcohol

c) Phenol

d) Nitrosobenzene

Answer Key:

b) Benzyl alcohol

  

23. Identify X in the sequence given below.

a) 

b) 

c) 

d) 

Answer Key:

 

24. Among the following, the reaction that proceeds through an electrophilic substitution, is:

a) 

b) 

c) 

d) 

Answer Key:

  

25. The major product of the following reaction

a) 

b) 

c) 

d) 

Answer Key:

 

 

II. Short Answer Questions.

12th Chemistry

III. Long Answer Questions. 

12th Chemistry

IV. Exercise.   

12th Chemistry