Which of the following are secondary bromides ?

Options

A. `(CH_(3))_(2)CHBr`
B. `(CH_(3))_(3)CCH_(2)Br`
C. `CH_(3)CH(Br)CH_(2)CH_(3)`
D. `(CH_(3))_(2)CBrCH_(2)CH_(3)`

Explanation

To determine which of the given compounds are secondary bromides, we need to identify the structure of each compound and analyze the carbon atom to which the bromine atom is attached (the alpha carbon). A secondary bromide is characterized by having the alpha carbon bonded to two alkyl groups.

### Step-by-Step Solution:

1. **Identify the Alpha Carbon**:
- For each compound, locate the carbon atom that is directly bonded to the bromine atom. This carbon is referred to as the alpha carbon.

2. **Count the Alkyl Groups**:
- Examine the alpha carbon and count how many alkyl groups (carbon-containing groups) are attached to it.
- An alkyl group is typically a carbon chain or a single carbon atom (like -CH3).

3. **Determine the Type of Bromide**:
- If the alpha carbon is attached to two alkyl groups, classify the compound as a secondary bromide.
- If the alpha carbon is attached to one or no alkyl groups, classify it as a primary or tertiary bromide, respectively.

4. **Analyze Each Option**:
- **Option 1**: The alpha carbon has two CH3 groups and one bromine. This carbon is attached to two alkyl groups (both CH3), making it a secondary bromide.
- **Option 2**: The alpha carbon has three CH3 groups and one bromine. This carbon is attached to three alkyl groups, making it a tertiary bromide.
- **Option 3**: The alpha carbon has one CH3 group and one CH2 group, with bromine attached. This carbon is attached to two alkyl groups (CH3 and CH2), making it a secondary bromide.
- **Option 4**: The alpha carbon has three CH3 groups and one bromine. This carbon is attached to three alkyl groups, making it a tertiary bromide.

5. **Conclusion**:
- The compounds that are classified as secondary bromides are from **Option 1** and **Option 3**.

### Final Answer:
The secondary bromides are **Option 1 and Option 3**.