In Melamine the total number of N- atoms having `sp^(2)` hybridisation are?

Answer

To determine the total number of nitrogen atoms having `sp²` hybridization in melamine, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Melamine**:
- Melamine has a chemical structure that includes a triazine ring. The structure consists of three nitrogen atoms in a ring and three amine (NH₂) groups attached to the ring.

2. **Count the Nitrogen Atoms**:
- In the structure of melamine, there are a total of **6 nitrogen atoms**: 3 in the ring and 3 from the NH₂ groups.

3. **Determine the Hybridization of Each Nitrogen Atom**:
- To find the hybridization of nitrogen atoms, we use the formula:
\[ \text{Hybridization} = \frac{\text{Valence Electrons} + \text{Number of Single Bonds} + \text{Charge}}{2} \]
- For nitrogen, the number of valence electrons is **5**.

4. **Analyze the Nitrogen Atoms in the NH₂ Groups**:
- Each nitrogen in the NH₂ group has:
- Valence Electrons = 5
- Single Bonds = 2 (one bond with each hydrogen)
- Charge = 0
- Calculation:
\[ \text{Hybridization} = \frac{5 + 2 + 0}{2} = \frac{7}{2} = 3.5 \quad \text{(not applicable)} \]
- Since this calculation does not yield a whole number, we can analyze it qualitatively: The nitrogen in NH₂ is `sp³` hybridized because it forms three sigma bonds (2 with H and 1 with the ring).

5. **Analyze the Nitrogen Atoms in the Ring**:
- Each nitrogen in the triazine ring has:
- Valence Electrons = 5
- Single Bonds = 1 (bond with the adjacent carbon or nitrogen in the ring)
- Charge = 0
- Calculation:
\[ \text{Hybridization} = \frac{5 + 1 + 0}{2} = \frac{6}{2} = 3 \]
- A hybridization number of 3 indicates that these nitrogen atoms are `sp²` hybridized.

6. **Count the Total Number of `sp²` Hybridized Nitrogen Atoms**:
- There are **3 nitrogen atoms in the ring** that are `sp²` hybridized.

### Final Answer:
The total number of nitrogen atoms having `sp²` hybridization in melamine is **3**.

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