The hybridization states of the nitrogen atom in pyridine piperidine and pyrrole are respectively

Options

A. `sp^(2),sp^(3)andsp^(2)`
B. `sp^(2),sp^(2)andsp^(2)`
C. `sp^(3),sp^(3)andsp^(3)`
D. `sp^(2),sp^(3)andsp^(3)`

Explanation

To determine the hybridization states of the nitrogen atom in pyridine, piperidine, and pyrrole, we need to analyze the structures of each compound and calculate the steric number for the nitrogen atom in each case. The steric number (S) is calculated as the sum of the number of sigma bonds and the number of lone pairs of electrons on the nitrogen atom. The hybridization can then be inferred from the steric number.

### Step 1: Analyze the structure of Pyridine
- **Structure**: Pyridine is a six-membered aromatic ring with five carbon atoms and one nitrogen atom. The nitrogen atom is part of the aromatic system and has one lone pair of electrons.
- **Sigma Bonds**: In pyridine, the nitrogen forms one sigma bond with a carbon atom. The remaining bonds in the ring are pi bonds due to the aromatic nature.
- **Lone Pairs**: The nitrogen has one lone pair of electrons.
- **Steric Number Calculation**:
- Number of sigma bonds = 1 (with carbon)
- Lone pairs = 1
- Steric Number (S) = 1 + 1 = 2
- **Hybridization**: Since S = 2, the hybridization of nitrogen in pyridine is **sp**.

### Step 2: Analyze the structure of Piperidine
- **Structure**: Piperidine is a six-membered saturated ring with five carbon atoms and one nitrogen atom. The nitrogen atom is bonded to two carbon atoms and has two hydrogen atoms attached.
- **Sigma Bonds**: The nitrogen in piperidine forms three sigma bonds (two with carbon and one with hydrogen).
- **Lone Pairs**: The nitrogen does not have any lone pairs in this case.
- **Steric Number Calculation**:
- Number of sigma bonds = 3
- Lone pairs = 0
- Steric Number (S) = 3 + 0 = 3
- **Hybridization**: Since S = 3, the hybridization of nitrogen in piperidine is **sp²**.

### Step 3: Analyze the structure of Pyrrole
- **Structure**: Pyrrole is a five-membered ring consisting of four carbon atoms and one nitrogen atom. The nitrogen atom is bonded to one carbon atom and has one hydrogen atom attached.
- **Sigma Bonds**: The nitrogen in pyrrole forms two sigma bonds (one with carbon and one with hydrogen).
- **Lone Pairs**: The nitrogen has one lone pair, but this lone pair participates in resonance with the pi system of the ring.
- **Steric Number Calculation**:
- Number of sigma bonds = 2
- Lone pairs = 1 (but this lone pair is involved in resonance and is not counted)
- Steric Number (S) = 2 + 0 = 2
- **Hybridization**: Since S = 2, the hybridization of nitrogen in pyrrole is **sp**.

### Final Answer:
The hybridization states of the nitrogen atom in pyridine, piperidine, and pyrrole are respectively **sp**, **sp²**, and **sp**.