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Xam Idea Class 12 Chemistry Chapter 13 Solutions: Amines

Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines comprehensively yet precisely cover all important concepts of this chapter. They have been written by experts in chemistry. These solutions follow the guidelines given by CBSE syllabus and NCERT books. Referring to our Xam Idea Solutions will lead you to perform well in the exams and pursue your desired course in higher studies.

Part A of our solutions contains a detailed description of all concepts of the chapter and stepwise answers to the questions asked at the end. The questions are based on analytical, memory and thinking skills. Some of them are very short answer questions, short answer questions and long answer questions. Some of them are multiple-choice questions, assertion reasoning questions, match the following questions and fill in the blank questions. Part B of our solutions contains elaborated answers to question papers based on the latest CBSE exam pattern. It also contains some fully solved model papers.

This chapter tells you that amines are considered as derivatives of ammonia, where ammonia has a pyramid-shaped structure. You learn that amines are classified as primary, secondary and tertiary and what are their common and IUPAC names. You also learn about key methods of preparation of amines, the properties of amines, and how to differentiate between primary, secondary and tertiary amines by using chemical reagents. This chapter also describes the preparation methods of diazonium salts and their importance in the synthesis of other aromatic compounds and azo dyes.

Important Topics for Xam Idea Class 12 Chemistry Chapter 13 – Amines

Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines explicitly talk about all the concepts of this chapter. They give you complete knowledge of the subject matter. The main points given in this chapter are as follows.

  • Structure of Amines and Their Classification

Amines are obtained by replacement of hydrogen atoms of NH3 molecule with alkyl or aryl groups. You learn here how to classify amines into primary, secondary and tertiary types. Upon replacement of one hydrogen atom of ammonia, we obtain primary amine with a structure of R NH2. Secondary amines have a characteristic structure of R2NH or R-NHR′, and tertiary amines are R3N, RNR′R′′ or R2NR′.

Amines are known as simple amines when the alkyl or aryl groups attached to nitrogen atom are the same in secondary and tertiary amines. When they have different groups attached to the nitrogen, then they are known as mixed amines. All the three types of amines behave as Lewis bases like ammonia, this basicity is due to one unshared electron pair on the nitrogen atom. Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines provide you with the best tips to remember the concepts learnt.

  • Nomenclature of Amines

This part of the chapter teaches you that amines can be named according to a common system as well as the IUPAC system. In the common system, an aliphatic amine gets the name of the alkyl group as a prefix to the word amine, and in IUPAC system, amines are named as alkanamines in case of aliphatic amines and area mines.

  • Preparation of Amines

In this portion of the chapter, you learn about processes for the preparation of aliphatic and aromatic amine compounds. Amines are prepared by reducing nitro compounds. The reduction can be carried out through passing hydrogen gas in the presence of metal catalysts. Amines can also be prepared by performing ammonolysis of alkyl halides, reducing nitriles or amides in the presence of lithium aluminium hydrides.

Here you will also learn that new amines can be prepared by Gabriel phthalimide synthesis and Hoffman bromamide degradation reaction using primary amines as starting materials. Our Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines are the best study material on amines, and they help you to ace in class 12 board exams.

  • Physical Properties of Amines

This part of the chapter discusses the physical properties of aliphatic and aromatic amines. The N-H bond is polar, and the nitrogen atom has a lone pair on it, these two factors govern both the physical and chemical properties of amines. Here you will also learn that lower primary and secondary amines are soluble in water because they exhibit hydrogen bonding with water molecules. This part further tells you that there are three factors influencing the stability of ammonium cations (substituted) of alkylamines — electron releasing ability of attached alkyl groups, steric factors and hydrogen bonding in polar protic solvents. These factors affect the basic nature of amines.

Alkylamines behave as stronger bases compared to ammonia due to the electron releasing nature of the alkyl group which end up in increasing the density of electrons on N atoms. In aromatic amines, electron releasing groups attached to the ring increase the basic character and electron-withdrawing groups decrease the basic character. Ammonia is a stronger base than aniline. Our Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines are written and verified by best teachers of chemistry.

  • Chemical Properties of Amines

This part of the chapter mentions the vast arena of chemical reactions shown by amines. As amines are Lewis bases, they react with acids producing salts. Reactions of amines are influenced by the presence of the unshared pair of electrons on nitrogen. Here you will also learn that the number of hydrogen atoms on the nitrogen atom influence the type of reaction amines undergoes. The products obtained out of the chemical reactions can form a basis for the distinction between primary, secondary and tertiary amines.

Further, you come to know that amines undergo alkylation and acylation reactions with alkyl halides and acyl halides, respectively. Aliphatic and aromatic primary amines undergo a signature reaction called carbylamine reaction when treated with ethanolic KOH and CHCl3. Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines help you to remember all the chemical reactions and formulas.

You further come to know that amines react with nitrous acid prepared in situ, where primary amines form aliphatic diazonium salts, and aromatic amines give arene diazonium salts.  Reaction with Hinsberg’s reagent (benzene sulphonyl chloride) gives corresponding sulphonamides, and this is utilized as a reaction to distinguish among primary, secondary and tertiary amines. Also, the reaction with p-Toluenesulfonyl chloride is used for the identification of primary, secondary and tertiary amines.

Next, you learn that aliphatic amines undergo electrophilic substitution like bromination, nitration, sulphonation with suitable reagents. The amino group present in the aromatic ring increases the reactivity of the aromatic amines. This reactivity can be controlled by treating aromatic amine with CH3COCl/(CH3CO)2O. Our Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines are very helpful during the revision of Class 12 Chemistry Amines.

  • Diazonium Salts

In this portion of the chapter, a very important derivative of amines is discussed, these are diazonium salts. Alkyl diazonium salts though can be prepared, are unstable and decompose easily. Here you will also learn that aryldiazonium salts which are obtained from arylamines are of more importance. These aryldiazonium salts are reacted further with different reagents where replacement of the diazonium group with a variety of nucleophiles yields phenols, aryl halides, cyanides and arenes. Coupling reactions of aryldiazonium salts with arylamines or phenols produce azo dyes which are of much commercial importance.

Exercise Discussion for Xam Idea Class 12 Chemistry Chapter 13 – Amines

There are several multiple-choice type, assertion reasoning type, match the following type, and fill in the blank questions given at the end of the chapter. Here you will also find very short answer questions, short answer and long answer type questions. Given below is a summary of the questions asked in this chapter. Our Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines provide perfect answers to all these questions.

This chapter has 22 VSAQs which ask you to provide IUPAC names to the given formulas, distinguish between two chemicals using a chemical reaction, to arrange the given series of compounds according to a given property, to provide synthetic steps for conversion of one compound to the other, to give a method of identification of the given compound.

Further, there are 27 SAQs which ask you to bring about conversion from starting material to product, to provide products of chemical reactions, solve word problems with a sequence of reactions, where you need to predict the product at each step, to write the chemical reaction of given starting material with nitrous acid.

At last, there are 19 LAQs which need you to provide reasons, give explanations, provide preparation methods, predict products of given reactions in case of aliphatic and aromatic amines, bring about conversion from starting material to product, to provide products of chemical reactions.

These questions give you an ample amount of practice on different concepts learnt about amines and its properties. Part B of Our solutions has several fully solved model papers and previous year’s question papers. You are advised to practice them so that you can get accustomed to the exam pattern and the exam environment.

Benefits of Xam Idea Class 12 Chemistry Chapter 13 – Amines

Some of the major benefits of learning and revising from our Xam Idea Class 12 Chemistry Solutions Chapter 13 – Amines are as follows.

  • They cover the fundamental concepts of amines and their derivatives thoroughly as this is a very important topic of organic chemistry.
  • They are concise, fully accurate and facilitate fast and effective learning and revision during your board exams.
  • They teach you to solve related questions step by step so that you can fare well in your board exams.
  • They follow all the latest guidelines given by CBSE and NCERT.
  • They have been designed to clear all your doubts and improve your retention rate.
  • They have been solved using the best methods of solving the problems.
  • They include detailed explanations, relevant examples, and illustrative diagrams to help you learn efficiently.
  • Our smart study techniques and learning shortcuts help you learn quickly and score more marks.
  • They are well-structured and follow a logical flow.