At room temperature, the staggered and eclipsed conformers of ethane continuously change into each other. This is because

Options

A. they are very unstable
B. C-C bond is flexible
C. the energy barrier between the two is not large enough to prevent rotation
D. C atom in ethane has a tetrahedral nature.

Explanation

To answer the question "At room temperature, the staggered and eclipsed conformers of ethane continuously change into each other. This is because", we need to analyze the options provided and understand the underlying concepts of conformational isomerism in ethane.

### Step-by-Step Solution:

1. **Understanding Conformers**:
- Ethane (C2H6) can exist in different spatial arrangements called conformers. The two most significant conformers are staggered and eclipsed.
- In the staggered conformation, the hydrogen atoms on adjacent carbons are positioned 60 degrees apart, minimizing steric hindrance.
- In the eclipsed conformation, the hydrogen atoms are aligned with each other, leading to increased steric repulsion.

2. **Energy Considerations**:
- The staggered conformation is more stable than the eclipsed conformation because it has lower energy due to reduced steric hindrance.
- The energy difference between the staggered and eclipsed conformations is approximately 3 kcal/mol. This small energy barrier allows for easy interconversion between the two forms.

3. **Bond Flexibility**:
- The C-C bond in ethane is flexible, allowing for rotation around the bond. This flexibility is crucial for the interconversion of staggered and eclipsed conformers.
- However, simply stating that the C-C bond is flexible does not fully explain why the conformers continuously change into one another.

4. **Thermal Energy at Room Temperature**:
- At room temperature, there is sufficient thermal energy available to overcome the energy barrier of 3 kcal/mol. This thermal energy facilitates the rapid conversion between staggered and eclipsed conformers.
- Therefore, the continuous change between these conformers is primarily due to the fact that the energy barrier is not large enough to prevent rotation.

5. **Conclusion**:
- The correct reason for the continuous interconversion of staggered and eclipsed conformers of ethane at room temperature is that the energy barrier between the two is not large enough to prevent rotation.

### Final Answer:
At room temperature, the staggered and eclipsed conformers of ethane continuously change into each other because the energy barrier between the two is not large enough to prevent rotation.