The two bonds N = O and N - O in `H_3CNO_2` are of same bond length due to

Options

A. Inductive effect
B. Hyperconjugation
C. Electrometric effect
D. Resonance effect

Answer

To determine why the two bonds N=O and N-O in H3CNO2 have the same bond length, we can analyze the structure and resonance of the molecule step by step.

### Step-by-Step Solution:

1. **Identify the Structure of H3CNO2**:
- H3CNO2 (Nitromethane) consists of a carbon atom bonded to three hydrogen atoms, one nitrogen atom, and two oxygen atoms. The nitrogen is bonded to one oxygen with a double bond (N=O) and to another oxygen with a single bond (N-O).

2. **Understand Resonance**:
- The molecule exhibits resonance, which means that the actual structure is a hybrid of multiple contributing structures. In this case, the resonance involves the shifting of electrons between the N=O and N-O bonds.

3. **Draw Resonance Structures**:
- The resonance structures can be drawn by moving the electrons from the N=O bond to the N-O bond. This results in a structure where the N-O bond can gain some double bond character while the N=O bond can lose some double bond character.

4. **Bond Character**:
- Due to resonance, the N=O bond and the N-O bond do not exist as purely double or single bonds. Instead, they have characteristics of both. This leads to the concept of partial bond character, where both bonds have a bond length that is intermediate between that of a typical double bond and a single bond.

5. **Conclusion**:
- The reason the two bonds (N=O and N-O) have the same bond length is due to resonance. The resonance allows for the delocalization of electrons, resulting in both bonds having similar bond lengths due to their partial double bond character.