A compound whose molecule is superimposabel on its mirror image despite containing chiral carbon atoms is called:

Options

A. Threo isomer
B. Meso compound
C. Enantiomer
D. No special name

Explanation

To solve the question, we need to understand the concept of isomerism, particularly focusing on the definition of a meso compound.

### Step-by-Step Solution:

1. **Understanding Chiral Centers**:
- A chiral carbon atom is one that is bonded to four different groups. This asymmetry allows for non-superimposable mirror images, known as enantiomers.

2. **Definition of Meso Compounds**:
- A meso compound contains chiral centers but is superimposable on its mirror image. This means that even though the molecule has chiral centers, the overall molecule has a plane of symmetry.

3. **Identifying Meso Compounds**:
- To identify a meso compound, one must look for a molecule that has chiral carbon atoms but also has a symmetry that allows it to be superimposed on its mirror image.

4. **Example of a Meso Compound**:
- Consider a molecule like tartaric acid, which has two chiral centers. However, due to its symmetrical arrangement, it can be superimposed on its mirror image, making it a meso compound.

5. **Conclusion**:
- Therefore, the answer to the question is that a compound whose molecule is superimposable on its mirror image despite containing chiral carbon atoms is called a **meso compound**.

### Final Answer:
A compound whose molecule is superimposable on its mirror image despite containing chiral carbon atoms is called a **meso compound**.

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