Chemistry Answer the following in one or two sentence.

a. Ethylamine reacts with acetic anhydride to give N-acetylethylamine.

b. Diethylamine reacts with acetic anhydride to give monoacetyl derivative.

Hoffmann bromamide reaction:
a) Primary amine can be prepared by reaction of amide with bromine and aqueous or alcoholic sodium hydroxide.

eg. Ethanamine is prepared by reaction of propanamide with bromine and aqueous or alcoholic sodium hydroxide.

b) This reaction is known as Hoffmann bromamide degradation. It involves molecular rearrangement. An alkyl or aryl group migrates from the carbonyl carbon to the adjacent nitrogen atom.
c) This reaction is useful for decreasing the length of carbon chain by one carbon atom.

It help to distinguish between primary and secondary amines

1-nitropropane and 2-nitropropane are prepared by oxidising propionaldehyde oxime and propan-2-one oxime with the help of trifluoroacetic acid.

1-nitropropane and 2-nitropropane are prepared by oxidising propionaldehyde oxime and propan-2-one oxime with the help of trifluoroacetic acid.

Methyl iodide reacts with alcoholic solution of potassium cyanide (KCN) to give ethane nitrile (or methyl cyanide) as the major product with a small amount of potassium iodide.

Ethane nitrile (or methyl cyanide) on reduction with sodium and alcohol (Mendius reaction) forms ethyl amine.

Nitrogen atom of amines contains a lone pair of electrons which can be donated. Thus, amines act as Lewis bases. Amines are Lowry-Bronsted bases as they accept a proton. Thus, amines act as bases and nucleophiles.

eg.
a. The reaction of ethylamine with dilute hydrochloric acid results in the formation of ethyl ammonium chloride.

b. The reaction of aniline with dilute hydrochloric acid results in the formation of anilinium chloride.

a. Resonance structure of aniline:
In aniline and other arylamines, the amino group is directly attached to benzene ring. Conjugation of lone pair of electrons stabilizes aniline. The lone pair is not easily available for protonation. Five resonance structures of aniline are as follows:

b. Action of benzene diazonium chloride on ethanol:
Reduction of benzene diazonium chloride in the presence of ethanol gives benzene. The ethanol gets oxidized to ethanal.

a. Nitroethane is reduced to ethylamine by the action of lithium aluminium hydride in the presence of ether.

b. 2 - Methyl - 1 - nitropropane is reduced to 2 - methylpropan - 1 - amine by the action of lithium aluminium hydride in the presence of ether.

The reaction of benzenediazonium chloride with phenol in mild alkaline medium yields p-hydroxyazobenzene (orange dye).

The reaction of benzenediazonium chloride with aniline in mild alkaline medium yields p-aminoazobenzene (yellow dye).