Predict the product of the reaction given below :
`CH_3-CH_2-CH=CH_2underset("Peroxide or light")overset(HBr)to`

Options

A. `CH_3-CH_2-CH_2-Br`
B. `CH_3-CH(Br)-CH_3`
C. `BrCH_2-CH=CH_2`
D.

Answer

To predict the product of the reaction given below:

**Reaction:**
\[ \text{CH}_3-\text{CH}_2-\text{CH}=\text{CH}_2 \xrightarrow{\text{Peroxide or light}} \text{HBr} \]

### Step-by-Step Solution:

1. **Identify the Reactants:**
The reactant is 1-butene (CH3-CH2-CH=CH2) and it is reacting with HBr in the presence of peroxide or light.

2. **Understand the Role of Peroxide:**
The presence of peroxide indicates that the reaction will follow the anti-Markovnikov rule. This means that the bromine (Br) will add to the less substituted carbon of the double bond.

3. **Identify the Double Bond:**
The double bond in 1-butene is between the second and third carbon atoms (C2 and C3).

4. **Apply the Anti-Markovnikov Rule:**
According to the anti-Markovnikov rule, the bromine (Br) will attach to the carbon that has more hydrogen atoms (C2), while the hydrogen (H) will attach to the carbon that has fewer hydrogen atoms (C3).

5. **Draw the Product:**
- The hydrogen atom (H) will add to C3 (the carbon with fewer hydrogen atoms).
- The bromine atom (Br) will add to C2 (the carbon with more hydrogen atoms).
- Therefore, the product formed will be 1-bromobutane.

6. **Write the Final Product:**
The final product of the reaction is:
\[ \text{CH}_3-\text{CH}_2-\text{CH}_2-\text{Br} \]
which is named **1-bromobutane**.

### Final Answer:
The product of the reaction is **1-bromobutane**.

---