For phenol which ofthe following resonating structure is the most stable ?

Options

A.
B.
C.
D. All haveequal stability

Answer

To determine which resonating structure of phenol is the most stable, we will follow a systematic approach based on the rules of resonance stability. Here are the steps:

### Step 1: Identify the Resonating Structures of Phenol
Phenol (C6H5OH) has several resonating structures. The primary structures can be drawn by moving the electrons in the π-bonds and lone pairs around the aromatic ring and the hydroxyl (–OH) group.

### Step 2: Count the Number of π-bonds
According to the first rule, the stability of a resonating structure increases with the number of π-bonds. Each structure should be analyzed to see how many π-bonds it contains.

### Step 3: Evaluate Charge Distribution
Next, we need to evaluate the charge distribution in each structure. Neutral species are generally more stable than charged species. If a structure has charges, we need to determine if they are positive or negative and where they are located.

### Step 4: Consider Electronegativity of Atoms
If there are charges present, we need to check if negative charges are on more electronegative atoms (like oxygen) and positive charges are on less electronegative atoms (like carbon). A negative charge on oxygen is more stable than on carbon.

### Step 5: Analyze Charge Separation
Lastly, we should look at the separation of opposite charges. If charges are closer together, the structure is more stable. If they are far apart, it leads to instability.

### Conclusion
After analyzing the resonating structures of phenol based on the above rules, we find that the structure where the negative charge is on the oxygen atom and the positive charge is on the adjacent carbon atom is the most stable. This is because it has a neutral structure with a favorable charge distribution and minimal charge separation.

### Final Answer
The most stable resonating structure of phenol is the one where the negative charge is on the oxygen atom and the positive charge is on the adjacent carbon atom.

---