Which of the following is known as gem - dibromide ?

Options

A. `CH_3CH(Br)CH(Br)CH_3`
B. `CH_2(Br)CH_2CH_2`
C. `CH_2BrCH_2Br`
D. `CH_3CBr_2CH_3`

Answer

To determine which compound is known as gem-dibromide, we need to understand the definition of gem-dihalides. A gem-dihalide is a compound where two halogen atoms are attached to the same carbon atom.

### Step-by-Step Solution:

1. **Understanding Gem-Dihalides**:
- Gem-dihalides are compounds where two halogen atoms (in this case, bromine) are bonded to the same carbon atom.

2. **Analyzing the Given Options**:
- We need to look at the structural formulas of the compounds provided in the options (A, B, C, D) to identify which one has two bromine atoms attached to the same carbon atom.

3. **Identifying the Structure**:
- Let's consider the structure of a compound that would be classified as a gem-dibromide.
- For example, if we have a structure like CH3-C(Br)2-CH3, this indicates that two bromine atoms are attached to the same carbon atom (the central carbon in this case).

4. **Finding the Correct Option**:
- By examining the structures in the options, we find that option D corresponds to the structure CH3-C(Br)2-CH3, which is indeed a gem-dibromide.

5. **Conclusion**:
- Therefore, the correct answer is option D, which is known as gem-dibromide.

### Final Answer:
**Option D is the correct answer.**

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