Which of the following on reaction with `NH_(3)` gives urinary antiseptic compound

Options

A. `HCHO`
B. `CH_(3)CHO`
C. `C_(6)H_(5)CHO`
D. `C_(6)H_(5)CH_(2)CHO`

Answer

To solve the question of which compound reacts with ammonia (NH₃) to give a urinary antiseptic compound, we will follow these steps:

### Step 1: Identify the Reaction
We need to determine which compound reacts with ammonia to form a urinary antiseptic. The key compound we are looking for is formaldehyde (HCHO).

### Step 2: Understand the Reaction
Formaldehyde reacts with ammonia to produce urotropin, which is a compound known for its antiseptic properties in urinary medicine. The reaction can be summarized as follows:

\[ \text{Formaldehyde} + \text{Ammonia} \rightarrow \text{Urotropin} \]

### Step 3: Structure of Urotropin
Urotropin has a specific structure consisting of four nitrogen atoms and methylene (-CH₂-) groups linking them. The structure can be represented as:

\[ \text{(NH₂)₂C(NH)₂} \]

This compound is also known as hexamethylenetetramine.

### Step 4: Conclusion
Based on the reaction and the structure of the product formed, we conclude that formaldehyde is the compound that reacts with ammonia to yield the urinary antiseptic compound, urotropin.

### Final Answer
The correct answer is **formaldehyde**.

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