Question

Give one chemical test to distinguish between the following pairs of compounds: Ethylamine and aniline

Answer 1

HELLO DEAR,

Ethylamine Is A Primary Aliphatic amine while aniline is a primary aromatic amine.

this may be distinguished by azo dye test :

$\bold{Azo\; dye \; tets}$ it involves the reaction of any aromatic primary amine with HNO2(NaNO2 + dil. HCl) at 273 — 278 Kelvin followed by treatment with an alkaline solution of 2—naphthol (Beta naphthol) when a brilliant Orange or red colour dye is obtained.

[see the attachment]

aliphatic primary amine ethylamine under these conditions give a brisk evolution of N2 gas with the formation of primary alcohol i.e the solution remains clear

$\bold{{C_2H_5NH_2} _{_{_{Ethylamine}}} + {HONO} ^{^{^{273-278K}}}\longrightarrow C_2H_5OH + N_2 \uparrow + H_2O}$

I HOPE IT'S HELP YOU DEAR,
THANKS

Answer 2

For the differentiation in the Aniline and Ethylamine, we will use the azo-dye test.

When we will react the aromatic amines at 0-5 degree with HNO2 (NaNO2 + dil. HCl) then the reaction will take place with the 2-naphthol with the alkaline solution.

The dye formed will have orange, red or yellow.

Whereas aliphatic amines will have the effervescence with the same condition.