When Lassiange extract of Methylamine react with `FeSO_(4)//"dilute" H_(2)SO_(4)` what happened ?

Answer

### Step-by-Step Solution:

1. **Understanding the Reaction Context**: The question involves the reaction of methylamine with a sodium fusion extract, followed by a reaction with iron(II) sulfate (FeSO4) in the presence of dilute sulfuric acid (H2SO4). The lecine test is primarily used to identify nitrogen, sulfur, phosphorus, and halogens in organic compounds.

2. **Identifying the Components**: Methylamine (CH3NH2) is an organic amine containing nitrogen. The sodium fusion extract is a method used to convert nitrogen in organic compounds into a soluble ionic form.

3. **Reaction with Sodium Fusion Extract**: When methylamine reacts with the sodium fusion extract, the covalent bond between carbon and nitrogen in methylamine is converted into an ionic bond. This process allows the nitrogen to be detected in subsequent reactions.

4. **Reaction with FeSO4 and Dilute H2SO4**: After the sodium fusion extract, the resulting solution is treated with iron(II) sulfate (FeSO4) and dilute sulfuric acid (H2SO4). In this step, the ionic form of nitrogen reacts with FeSO4 to form a complex.

5. **Formation of Prussian Blue**: The final product of this reaction is Prussian blue, which is a complex formed when iron ions react with cyanide ions. The formula for Prussian blue is Fe₄[Fe(CN)₆]₃·xH₂O, indicating that it contains iron and cyanide ions.

6. **Conclusion**: Therefore, when the lecine extract of methylamine reacts with FeSO4 in the presence of dilute H2SO4, it results in the formation of Prussian blue.

### Final Answer:
When the lecine extract of methylamine reacts with FeSO4 in the presence of dilute H2SO4, it produces Prussian blue (Fe₄[Fe(CN)₆]₃·xH₂O).

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