In the given reaction `C_6H_5CH_2COOHoverset((i)NH_3//Delta)underset((ii) P_2O_5)rarr(X)`
(X) will be

Options

A. `C_6H_5-CH_2COONH_4`
B. `C_6H_5-CH_2CONH_2`
C. `C_6H_5-CH_2-CN`
D. `C_6H_5CN`

Answer

To solve the given reaction \( C_6H_5CH_2COOH \overset{(i) NH_3/\Delta}{\underset{(ii) P_2O_5}{\rightarrow}} (X) \), we will follow these steps:

### Step 1: Identify the Reactants
The reactant is benzoic acid with the structure \( C_6H_5CH_2COOH \). This is a carboxylic acid.

### Step 2: Reaction with Ammonia
When benzoic acid reacts with ammonia (\( NH_3 \)) under heating, it forms an ammonium salt. The reaction can be represented as:
\[ C_6H_5CH_2COOH + NH_3 \rightarrow C_6H_5CH_2COO^- NH_4^+ \]
Here, the carboxylic acid donates a proton to ammonia, forming the ammonium salt of the carboxylic acid.

### Step 3: Dehydration with P2O5
Next, we treat the ammonium salt with phosphorus pentoxide (\( P_2O_5 \)), which is a strong dehydrating agent. This step will remove water from the ammonium salt, leading to the formation of an amide. The dehydration reaction can be represented as:
\[ C_6H_5CH_2COO^- NH_4^+ \xrightarrow{P_2O_5} C_6H_5CH_2C(O)NH_2 + H_2O \]
Here, the water molecule is eliminated, and we are left with the amide.

### Step 4: Final Structure of Product X
The final product \( X \) is the amide formed from the dehydration of the ammonium salt. The structure of \( X \) is:
\[ C_6H_5CH_2C(O)NH_2 \]
This is known as benzylacetamide.

### Conclusion
Thus, the final product \( X \) is benzylacetamide.

### Answer
The correct answer is option C: \( C_6H_5CH_2C(O)NH_2 \).

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