Question

In the following skew conformation of ethane, the \( H' - C - C - H'' \) dihedral angle is:

• A. 58°
• B. 149°
• C. 151°
• D. 120°

Hint:

The staggered conformation of ethane minimizes steric repulsion and results in a dihedral angle of approximately 149°.

Answer 1

The Correct Option is B

Step 1: Understanding the skew conformation.
The skew conformation of ethane has the hydrogen atoms on the two carbons in a staggered arrangement. This minimizes repulsion and gives the dihedral angle of 149°.

Step 2: Conclusion.
Therefore, the dihedral angle between \( H' - C - C - H'' \) is 149°.