Most stable radical is

Options

A.
B.
C. `CH_(2)=CHoverset(cdot)CH_(2)`
D. `CH_(2)=overset(cdot)CH.`

Explanation

To determine which radical is the most stable among the given options, we will analyze the stability based on resonance and hyperconjugation effects. Here’s a step-by-step solution:

### Step 1: Identify the Radicals
First, we need to identify the structures of the radicals given in the options. Each radical will have an unpaired electron, which is crucial for determining stability.

**Hint:** Look for the carbon atoms that have an unpaired electron (dot) in their structure.

### Step 2: Analyze Resonance
Next, we will check if the radicals can participate in resonance. Resonance occurs when there are multiple valid Lewis structures for a molecule, allowing the electron density to be delocalized.

- **Radical A:** Has a double bond adjacent to the radical, allowing resonance.
- **Radical B:** No resonance is possible as there are no adjacent double bonds.
- **Radical C:** Similar to Radical A, it has a double bond adjacent to the radical, allowing resonance.
- **Radical D:** No resonance is possible here as well.

**Hint:** Identify which radicals have adjacent double bonds that can stabilize the unpaired electron through resonance.

### Step 3: Compare Resonance Structures
For the radicals that can resonate (A and C), we will draw their resonance structures to see how many contributing structures can stabilize the radical.

- **Radical A:** Can form several resonance structures, contributing to its stability.
- **Radical C:** Also forms resonance structures, but we need to analyze how many are identical and how they compare to Radical A.

**Hint:** Count the number of resonance structures and check if they are identical or not.

### Step 4: Analyze Hyperconjugation
Next, we will consider hyperconjugation, which involves the interaction of the radical with adjacent C-H bonds. The more alkyl groups attached to the radical, the more stable it becomes due to hyperconjugation.

- **Radical A:** Has multiple adjacent hydrogen atoms contributing to hyperconjugation.
- **Radical C:** Also has adjacent hydrogen atoms, but we need to count them.

**Hint:** Look at the number of adjacent hydrogen atoms (alpha hydrogens) that can stabilize the radical through hyperconjugation.

### Step 5: Determine the Most Stable Radical
After analyzing resonance and hyperconjugation, we can conclude which radical is the most stable.

- **Radical A and C** have resonance, but if Radical C has more identical resonance structures and more alpha hydrogens, it will be more stable than Radical A.
- **Radicals B and D** do not have resonance and are less stable.

**Conclusion:** Based on the resonance and hyperconjugation analysis, **Radical C** is the most stable radical.

**Final Answer:** The most stable radical is **Option C**.