Formaldehyde reacts with excess of ammonia to give

Options

A. `CH_2=NH`
B.
C.
D. Hexamethylenetetramine

Answer

To solve the question regarding the reaction of formaldehyde with excess ammonia, we can follow these steps:

### Step 1: Identify the Reactants
- The reactants in this reaction are formaldehyde (HCHO) and ammonia (NH3).

### Step 2: Understand the Reaction
- When formaldehyde reacts with ammonia, it undergoes a condensation reaction. In this case, since there is excess ammonia, it will lead to the formation of a more complex product.

### Step 3: Determine the Product
- The major product formed when formaldehyde reacts with excess ammonia is hexamethylenetetramine (also known as urotropine). The molecular formula for hexamethylenetetramine is C6H12N4.

### Step 4: Write the Balanced Reaction
- The balanced chemical equation for the reaction can be represented as follows:
\[ 6 \text{HCHO} + 4 \text{NH}_3 \rightarrow \text{C}_6\text{H}_{12}\text{N}_4 + 6 \text{H}_2\text{O} \]
- This shows that 6 moles of formaldehyde and 4 moles of ammonia react to produce 1 mole of hexamethylenetetramine and 6 moles of water.

### Step 5: Draw the Structure of the Product
- The structure of hexamethylenetetramine consists of a central carbon atom bonded to six methylene (-CH2-) groups, with four nitrogen atoms also bonded to the carbon framework.

### Conclusion
- Therefore, the final answer to the question is that formaldehyde reacts with excess ammonia to give hexamethylenetetramine.

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