Identify 'B' in the reaction
Acetamide `underset(Delta)overset(P_(2)O_(5))rarrAoverset(4H)RarrB`

Options

A. `CH_(3)NH_(2)`
B. `CH_(3)CH_(2)NH_(2)`
C. `CH_(3)CN`
D. `CH_(3)COONH_(4)`

Explanation

To identify 'B' in the given reaction, we will analyze the transformation step by step.

### Step 1: Identify Acetamide
Acetamide is a nitrogen-containing compound with the formula CH₃CONH₂. It consists of an acetyl group (CH₃CO) and an amine group (NH₂).

### Step 2: Reaction with P₂O₅
When acetamide is heated with phosphorus pentoxide (P₂O₅), a dehydrating agent, it undergoes dehydration. During this reaction, water (H₂O) is removed, leading to the formation of a compound called methyl cyanide (or acetonitrile), which has the formula CH₃CN.

**Reaction:**
\[ \text{CH}_3CONH_2 \xrightarrow{\Delta, P_2O_5} \text{CH}_3CN + H_2O \]

### Step 3: Reaction of Methyl Cyanide (A)
The next part of the reaction involves methyl cyanide (CH₃CN) reacting in the presence of hydrogen (4H). This reaction is typically a reduction process where the cyanide group (C≡N) is converted to an amine group (NH₂).

**Reduction Reaction:**
\[ \text{CH}_3CN + 4H \rightarrow \text{CH}_3CH_2NH_2 \]

### Step 4: Identify 'B'
The product formed after the reduction of methyl cyanide is ethylamine, which has the formula CH₃CH₂NH₂.

### Conclusion
Thus, the compound 'B' in the reaction is ethylamine (CH₃CH₂NH₂).

### Final Answer:
B = Ethylamine (CH₃CH₂NH₂)

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