The pair of resonanating structures among the following is

Options

A. `R_(2)CH-N=O" "R_(2)C=N-OH`
B.
C.
D.

Answer

To solve the question regarding the pair of resonating structures, we will follow a systematic approach based on the rules of resonance. Here’s a step-by-step solution:

### Step 1: Understand Resonating Structures
Resonating structures are different ways of drawing the same molecule that differ only in the distribution of electrons. They must follow certain rules to be considered valid.

### Step 2: List the Rules for Resonating Structures
1. **Hybridization must remain the same**: The hybridization of atoms in the structure should not change.
2. **Skeleton of the structure cannot change**: The connectivity of atoms must remain the same.
3. **Same number of lone pairs**: The number of lone pairs of electrons must be the same in both structures.

### Step 3: Analyze Each Option
We will analyze each given option based on the rules of resonance.

#### Option A: R2CH N=O and R2C=N-OH
- **Analysis**: The skeleton changes because a hydrogen atom is transferred from nitrogen to oxygen. This violates the second rule.
- **Conclusion**: Incorrect pair of resonating structures.

#### Option B: R2CH N⁺=O⁻ and R2C=N=O
- **Analysis**: The positive charge can shift to create a double bond between nitrogen and oxygen, while maintaining the same skeleton and number of lone pairs.
- **Conclusion**: This is a valid pair of resonating structures.

#### Option C: R2CH-N-H and R2C=O-H
- **Analysis**: The hydrogen atom moves from nitrogen to oxygen, changing the skeleton. This violates the second rule.
- **Conclusion**: Incorrect pair of resonating structures.

#### Option D: R2CH N⁺=O⁻ and R2C=N=O
- **Analysis**: The structure changes the position of the negative charge and involves a change in the bonding pattern, which violates the second rule.
- **Conclusion**: Incorrect pair of resonating structures.

### Step 4: Final Conclusion
After analyzing all options, the only correct pair of resonating structures is **Option B**: R2CH N⁺=O⁻ and R2C=N=O.