Question

$2,4-\mathrm{DNP}$ test can be used to identify-

• A. Aldehyde
• B. Halogens
• C. Ether
• D. Amine

Answer 1

The correct option is A

Aldehyde

Explanation for the correct option:

B) Aldehyde:

Step 1: Identify the structure of $\mathbf{2}\mathbf{,}\mathbf{4}\mathbf{-}\mathbf{DNP}$:

Step 2: $\mathbf{2}\mathbf{,}\mathbf{4}\mathbf{-}\mathbf{DNP}$ reacts with Aldehyde $\left(R-\mathrm{CHO}\right)$:

1. When $2,4-\mathrm{DNP}$ reacts with Aldehydes, a coloured Ppt is formed.
2. Hence, it can be used to identify the carbonyl compounds, (i.e., Both Aldehydes and Ketones).
3. 

Explanation for incorrect options:

B) Halogens:

1. When $2,4-\mathrm{DNP}$ reacts with Halogens, no product is formed.
2. 

C) Ether:

1. When $2,4-\mathrm{DNP}$ reacts with Ethers, no reaction takes place.
2. 

D) Amine:

1. When $2,4-\mathrm{DNP}$ reacts with Amines, no reaction takes place.
2. 

Hence, option A is correct. $2,4-\mathrm{DNP}$ test can be used to identify aldehydes.