2,4 - DNP is obtained by reacting hydrazine hydrate with which of the following ?

Options

A.
B.
C.
D.

Answer

To solve the question of how 2,4-DNP (2,4-Dinitrophenylhydrazine) is obtained by reacting hydrazine hydrate, we can follow these steps:

### Step 1: Understand the Structure of 2,4-DNP
2,4-DNP stands for 2,4-Dinitrophenylhydrazine. It is derived from a phenyl compound that has two nitro groups (-NO2) at the 2nd and 4th positions on the benzene ring, along with a hydrazine group (-NH-NH2).

### Step 2: Identify the Reactant
To synthesize 2,4-DNP, we need to react hydrazine hydrate with a suitable compound that contains the necessary nitro groups. The compound that fits this requirement is 2,4-Dinitrochlorobenzene. This compound has two nitro groups at the 2nd and 4th positions and a chlorine atom that can be replaced by the hydrazine group.

### Step 3: Reaction Mechanism
When hydrazine hydrate reacts with 2,4-Dinitrochlorobenzene, the chlorine atom is substituted by the hydrazine group, resulting in the formation of 2,4-Dinitrophenylhydrazine. The reaction can be summarized as follows:

\[ \text{2,4-Dinitrochlorobenzene} + \text{Hydrazine hydrate} \rightarrow \text{2,4-Dinitrophenylhydrazine} + \text{HCl} \]

### Step 4: Conclusion
Thus, the correct answer to the question is that 2,4-DNP is obtained by reacting hydrazine hydrate with **2,4-Dinitrochlorobenzene**.

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