Question

Assertion: Acetic acid on reaction with $ hydrazoic{\text{ }}acid $ ( $ {N_3}H $ ) in the presence of $ {H_2}S{O_4} $ followed by heating and hydrolysis in basic medium gives $ acetamide $ .
Reason: $ Methyl{\text{ }}isocyanate $ ( $ Me - N = C = O $ ) is formed as an intermediate compound.
(A) Both assertion and reason are correct and reason is the correct explanation for assertion.
(B) Both assertion and reason are correct, but reason is not the correct explanation for assertion.
(C) Assertion is correct but reason is incorrect.
(D) Both assertion and reason are correct.

Answer 1

Hint :In the above question we are asked about the reaction of carbonyl derivative acetic acid with an azide $ hydrazoic{\text{ }}acid $ in the presence of $ sulphuric{\text{ }}acid $ . This is the Schmidt reaction which results in the formation of an amine.

Complete Step By Step Answer:
 $ Acetic\;acid $ is also known as the $ ethanoic{\text{ }}acid $ . It is a colourless liquid and has a pungent smell. $ Acetic\;acid $ is primarily used in the production of cellulose acetate for photographic film, polyvinyl acetate for wood glue and synthetic fibres and fabrics.
Schmidt reaction is a type of reaction where a carbonyl derivative like aldehyde, carboxylic acid or ketone undergoes reaction with an azide in the presence of an acid and results in the formation of amine, imide or amide. This reaction has considerable utility for the synthesis of hindered or cyclic amides and amines. Schmidt reaction is used for the synthesis of medium sized lactams and hindered amides.
When a carboxylic acid undergoes Schmidt reaction an amine is present and this product has one less carbon. The carboxylic acids give acyl azides which rearrange to isocyanates which are hydrolysed to carbamates.
On treating acetic acid with $ hydrazoic{\text{ }}acid $ in the presence of $ sulphuric{\text{ }}acid $ the product obtained is methylamine. The reaction is given below-
 $ C{H_3}COOH + NH_3^{} \to C{H_3}N{H_3} + C{O_2} + {N_2} $
So the assertion that it gives $ acetamide $ is false as the product formed is methyl amine.
Though the intermediate form is $ Methyl{\text{ }}isocyanate $ the structure given is not correct.
Therefore the correct option is D.

Note :
During the Schmidt reaction there is nitrogen evolved as a by-product. Also when this reaction takes place with carboxylic acid amine is formed, with ketone there if formation of amide and with alkene gives imine.