Among `Me_(3)N, C_(5)H_(5)N` and Me CN (Me= methyl group) , the electronegativity of N is the order

Options

A. `MeCN gt C_(5) H_(5) N gt Me_(3)N`
B. `C_(5) H_(5) N gt Me_(3) N gt MeCN`
C. `Me_(3) N gt MeCN gt C_(5) N_(5) N`
D. electronegativity is same in all

Explanation

To determine the order of electronegativity of nitrogen in the compounds Me₃N, C₅H₅N, and MeCN (where Me represents a methyl group), we can analyze the hybridization of nitrogen in each compound and its corresponding s-character.

### Step-by-Step Solution:

1. **Identify the Compounds**:
- The compounds given are Me₃N (trimethylamine), C₅H₅N (pyridine), and MeCN (methyl cyanide).

2. **Draw the Structures**:
- **Me₃N**: This compound has nitrogen bonded to three methyl groups. The structure can be represented as:
```
H H H
\ | /
C - N
/ | \
H H H
```
- **C₅H₅N**: This compound is pyridine, which has a nitrogen atom in a six-membered aromatic ring.
```
C
/ \
C N
/ \ / \
C C C
```
- **MeCN**: This compound has nitrogen bonded to a methyl group and a carbon atom in a triple bond.
```
H
|
C ≡ N
```

3. **Determine the Hybridization of Nitrogen**:
- **In Me₃N**: The nitrogen is sp³ hybridized because it forms three sigma bonds with methyl groups and has one lone pair.
- **In C₅H₅N**: The nitrogen is sp² hybridized because it forms two sigma bonds (one with carbon in the ring and one with another carbon) and has one lone pair.
- **In MeCN**: The nitrogen is sp hybridized because it forms one sigma bond with carbon and has one lone pair.

4. **Calculate the Percentage of s-character**:
- **sp³ (Me₃N)**: 25% s-character
- **sp² (C₅H₅N)**: 33.3% s-character
- **sp (MeCN)**: 50% s-character

5. **Determine the Electronegativity Order**:
- The more the s-character, the higher the electronegativity. Therefore, the order of electronegativity of nitrogen in these compounds is:
- MeCN (sp, 50% s-character) > C₅H₅N (sp², 33.3% s-character) > Me₃N (sp³, 25% s-character).

### Final Order of Electronegativity:
**MeCN > C₅H₅N > Me₃N**