Number of total resonating structures of cyclopendienly anion is :

Options

A. `2`
B. `3`
C. `4`
D. `5`

Explanation

To determine the total number of resonating structures of the cyclopentadienyl anion, we can follow these steps:

### Step 1: Understand the Structure of Cyclopentadienyl Anion
The cyclopentadienyl anion is derived from cyclopentadiene by adding an extra electron, resulting in a negative charge. The structure consists of a five-membered carbon ring with alternating double bonds and one additional electron contributing to the negative charge.

**Hint:** Draw the basic structure of cyclopentadiene and add a negative charge to visualize the anion.

### Step 2: Identify the Possible Resonance Structures
To find the resonance structures, we can move the electrons in the double bonds around the ring. The key is to ensure that the overall charge remains the same and that we only move electrons, not atoms.

**Hint:** Remember that resonance involves shifting pi electrons and lone pairs while keeping the overall connectivity of the molecule intact.

### Step 3: Draw the First Resonance Structure
Start with the original structure of the cyclopentadienyl anion. In this structure, we can have alternating double bonds.

**Hint:** Label the positions of the double bonds and the negative charge clearly.

### Step 4: Shift Electrons to Create New Structures
1. Move the electrons from one double bond to the adjacent single bond, creating a new double bond and shifting the negative charge.
2. Repeat this process around the ring to generate new resonance forms.

**Hint:** Each time you move the double bond, ensure that the negative charge is moved to the appropriate carbon atom.

### Step 5: Count the Unique Resonance Structures
After generating all possible structures by shifting the double bonds and the negative charge, count the unique resonance structures you have drawn.

**Hint:** Ensure that you do not double-count any structures that look the same.

### Step 6: Conclusion
After analyzing the cyclopentadienyl anion, you will find that there are a total of **5 unique resonance structures**.

**Final Answer:** The total number of resonating structures of the cyclopentadienyl anion is **5**.