Urotropine is obtained when

Options

A. urea reacts with formalin
B. urea reacts with ammonia
C. formaldehyde reacts with ammonia
D. acetone reacts with ammonia

Answer

To obtain urotropine (also known as hexamethylenetetramine), follow these steps:

### Step-by-Step Solution:

1. **Understanding the Reactants**:
Urotropine is synthesized from formaldehyde and ammonia. The chemical formula for formaldehyde is CH2O, and ammonia is NH3.

2. **Setting Up the Reaction**:
The reaction involves the combination of formaldehyde and ammonia. The reaction can be represented as:
\[ \text{Formaldehyde (CH2O)} + \text{Ammonia (NH3)} \rightarrow \text{Urotropine (C6H12N4)} + \text{Water (H2O)} \]

3. **Stoichiometry of the Reaction**:
For every molecule of urotropine formed, six molecules of water are released. The balanced reaction can be represented as:
\[ 6 \text{CH2O} + 4 \text{NH3} \rightarrow \text{C6H12N4} + 6 \text{H2O} \]

4. **Reaction Conditions**:
The reaction typically requires heating and may be conducted under acidic or basic conditions to facilitate the removal of water and drive the reaction towards the formation of urotropine.

5. **Final Product**:
After the reaction is complete, urotropine (hexamethylenetetramine) is obtained as a white crystalline solid. It can be purified through recrystallization if necessary.

### Summary:
Urotropine is obtained by the reaction of formaldehyde with ammonia, resulting in the formation of hexamethylenetetramine and the release of water.

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