Question

║⊕QUESTION⊕║
Undeniable chemistry and horrific timing. They love each other.
↓
CLASS 12
ORGANIC CHEMISTRY
↑
Give tests to distinguish the following:
1) Methylamine and N - methylamine
2) Aniline and Methylamine
3) Ethanal and acetone
4) Vinyl halide and Allyl Halide

Answer 1

Answer:

1. Methylamine (being an aliphatic primary amine) gives a positive carbylamine test, but dimethylamine does not. Aniline and benzylamine can be distinguished by their reactions with the help of nitrous acid, which is prepared in situ from a mineral acid and sodium nitrite

2.Methylamine and aniline :                          

Azo dye test.  

Aniline on diazotization ( ice cold nitrous acid solution) followed by coupling with 2-naphtol (in alkaline solution) forms brilliant orange or red dye. Methylamine will not form dye. It will give brisk effervescence (due to liberation of nitrogen gas) but solution remains clear.

3. acetaldehyde (systematic name ethanal)

There are several ways you can distinguish between an acetaldehyde and an acetone.

# One of the most common ways to allow both acetaldehyde and acetone to react with Tollen’s reagent. A silver mirror is formed when acetaldehyde reacts with Tollen’s reagent. No such compound is formed on reaction of the agent with acetone.

# When acetone is subject to iodoform test, a precipitate is formed. There will be no such reaction when acetaldehyde is subject to iodoform test.

# Fehling’s reagent and chromic acid test can help in the identification of an acetaldehyde.

Explanation: