The major product of reaction between n-butane and bromine at `130^(@)C` is

Options

A. `CH_(3)CH_(2)CH_(2)CH_(2)Br`
B. `CH_(3)CH_(2)underset(CH_(3))underset(|)(CH)Br`
C. `CH_(3)-underset(CH_(2)Br)underset(|)(CH_(2))CHBr`
D. `CH_(3)CH_(2)underset(CH_(3))underset(|)(CH)Br`

Explanation

To determine the major product of the reaction between n-butane and bromine at 130°C, we can follow these steps:

### Step 1: Understand the Reactants
- **Identify n-butane**: n-butane (C4H10) has the structure CH3-CH2-CH2-CH3.
- **Identify bromine**: Bromine (Br2) is a diatomic molecule that can participate in substitution reactions.

### Step 2: Reaction Conditions
- The reaction occurs at a high temperature (130°C), which favors radical reactions, specifically free radical bromination.

### Step 3: Initiation of the Reaction
- The reaction begins with the homolytic cleavage of the Br-Br bond, generating two bromine radicals (Br•).

### Step 4: Propagation Steps
- The bromine radical can abstract a hydrogen atom from n-butane, forming a butyl radical and HBr.
- The butyl radical can be either a primary (1°) or a secondary (2°) radical, depending on which hydrogen is abstracted.

### Step 5: Formation of Radicals
- **Primary Radical**: If a hydrogen from the terminal carbon is removed, a primary butyl radical (CH3-CH2-CH2-CH2•) is formed.
- **Secondary Radical**: If a hydrogen from the second carbon is removed, a more stable secondary butyl radical (CH3-CH2-CH•-CH3) is formed.

### Step 6: Stability of Radicals
- The secondary radical is more stable than the primary radical due to hyperconjugation and the inductive effect of the adjacent carbon atoms.

### Step 7: Termination Steps
- The secondary butyl radical can react with another bromine radical to form the major product: CH3-CH2-CHBr-CH3 (2-bromobutane).
- The primary radical can also react with a bromine radical, but it will yield a less stable product: CH3-CH2-CH2-CH2Br (1-bromobutane).

### Conclusion
- The major product of the reaction between n-butane and bromine at 130°C is 2-bromobutane (CH3-CH2-CHBr-CH3).

### Final Answer
The major product is **2-bromobutane**.

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