Melamine is used in formation of melamine formaldehye resin. How many nitrogen atoms are present in melamine unit.

Answer

To determine how many nitrogen atoms are present in a melamine unit, we can follow these steps:

### Step 1: Understand the Structure of Melamine
Melamine is an organic compound with the chemical formula C3H6N6. It consists of a triazine ring, which contains nitrogen atoms.

### Step 2: Draw the Structure of Melamine
The structure of melamine can be represented as follows:

```
N
/ \
C N
/ \ / \
N C N
\ / \ /
C N
\ /
N
```

In this structure, there are three nitrogen atoms in the ring and three amino (NH2) groups attached to the carbon atoms.

### Step 3: Count the Nitrogen Atoms
1. **Nitrogen in the Ring**: There are 3 nitrogen atoms present in the triazine ring.
2. **Nitrogen in the Amino Groups**: Each of the three NH2 groups contributes 1 nitrogen atom, adding 3 more nitrogen atoms.

### Step 4: Calculate the Total Number of Nitrogen Atoms
- Nitrogen from the ring: 3
- Nitrogen from the amino groups: 3
- Total nitrogen atoms = 3 (from the ring) + 3 (from the amino groups) = 6 nitrogen atoms.

### Final Answer
Melamine contains a total of **6 nitrogen atoms**.

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