Nitrogen Compounds

Question 1

List some ways in which amines are formed.

Answer 1

1. Reacting halogenoalkane with NH3 in ethanol under pressure
2. Reacting halogenoalkane with primary amine in ethanol under pressure
3. Reduction of Amides with LiAlH4
4. Reduction of nitriles with LiAlH4 or H2 /Ni

Question 2

Describe the preparation of phenylamine from benzene.

Answer 2

1. Bnezene is nitrated
2. Nitrobenzene is reduced under reflux with tin and conc HCl
3. The product formed is converted to phenylamine by adding NaOH

Question 3

How to form bromophenylamine?

Answer 3

React phenylamine with Bromine

Question 4

How to prepare an azo dye?

Answer 4

1. First nitric acid is formed by reacting sodium nitrite and HCl in a test tube
2. Phenylamine is added and benzenediazonium chloride (a diazonium ion) is formed
3. The diazonium ion is reacted with an alkaline solution of phenol to give an azo dye.

Question 5

What is formed from the acid hydrolysis of an amide?

Answer 5

1. A carboxylic acid and a primary amine.
2. The amine further reacts with HCl to form an ammonium salt

Question 6

What products are formed from the alkaline hydrolysis of an amide?

Answer 6

1. Sodium salt of the carboxylic acid and a primary amine

Question 7

What happens if we reflux an amide with acid or alkali?

Answer 7

1. With acid, a carboxylic acid and ammonia is formed. the ammonia further reacts with acid to form an ammonium salt
2. With alkali, the salt of a carboxylic acid and ammonia are formed

Question 8

How does a zwitterion behave as a buffer?

Answer 8

1. If an acid is added the -COO- part accepts the H+ and forms COOH and a postively charged ion is left
2. If an alkali is added the -NH3- part donates the H+, making NH2 and a negatively charged ion.