How many resonance structures are possible for allyl carbocation?

Answer

To determine how many resonance structures are possible for the allyl carbocation, we can follow these steps:

### Step 1: Understand the Structure of Allyl Carbocation
The allyl carbocation has the following structure:
- It consists of three carbon atoms, where one of the carbon atoms carries a positive charge.
- The structure can be represented as CH2=CH-CH2^+.

### Step 2: Identify the Resonance Structures
To find the resonance structures, we can move the double bond and the positive charge around:
1. The first resonance structure is the original structure: CH2=CH-CH2^+.
2. The second resonance structure can be formed by shifting the double bond between the first and second carbon atoms to the second and third carbon atoms, resulting in: CH2^+-CH=CH2.

### Step 3: Draw the Resonance Structures
- The first resonance structure is:
```
CH2=CH-CH2^+
```
- The second resonance structure is:
```
CH2^+-CH=CH2
```

### Step 4: Count the Resonance Structures
From the above analysis, we can see that there are two distinct resonance structures for the allyl carbocation.

### Final Answer
Thus, the total number of resonance structures possible for the allyl carbocation is **2**.

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