Which of the following statement is incorrect ?

Options

A. It is possible to separate eclipsed and staggered form of ethane at room temperature
B. Eclipsed from has torsional strain
C. Ethane has infinite number of conformers
D. Energy difference between staggered form & eclipsed form of ethane is `12.5 kJ//"mole"`

Explanation

To determine which statement is incorrect regarding the conformations of ethane, we will analyze each statement step by step.

### Step-by-Step Solution:

1. **Understanding Eclipsed and Staggered Forms**:
- Ethane (C2H6) can exist in different conformations. The two primary conformations are the **eclipsed** and **staggered** forms.
- In the **eclipsed form**, the hydrogen atoms on one carbon are directly aligned with the hydrogen atoms on the adjacent carbon. This leads to increased torsional strain due to electron repulsion.
- In the **staggered form**, the hydrogen atoms on one carbon are positioned between the hydrogen atoms on the adjacent carbon, minimizing electron repulsion and thus being more stable.

2. **Statement Analysis**:
- **Statement 1**: "It is possible to separate eclipsed and staggered form of ethane at room temperature."
- This statement is **incorrect**. The energy difference between the eclipsed and staggered forms is small (approximately 12.5 kJ/mol), making it impossible to separate them at room temperature since they interconvert rapidly.

- **Statement 2**: "Eclipsed form has torsion strain."
- This statement is **correct**. The eclipsed conformation experiences torsional strain due to the repulsion between the electron clouds of the overlapping hydrogen atoms.

- **Statement 3**: "Ethane has infinite number of conformers."
- This statement is **correct**. Ethane can rotate around the C-C bond, leading to an infinite number of possible conformations.

- **Statement 4**: "The energy difference between eclipsed and staggered forms is small."
- This statement is **correct**. The energy difference is indeed small, which is why the two forms cannot be separated at room temperature.

3. **Conclusion**:
- The only incorrect statement is **Statement 1**.

### Final Answer:
The incorrect statement is: "It is possible to separate eclipsed and staggered form of ethane at room temperature."