Question:
In the following skew conformation of ethane, $\mathrm{H}^{\prime}-\mathrm{C}-\mathrm{C}-\mathrm{H}^{\prime \prime}$ dihedral angle is :

Correct Option: , 2
Solution:

$\therefore$ Angle between $\mathrm{H}^{\prime}$ and $\mathrm{H}^{\prime \prime}=120^{\circ}+29^{\circ}=149^{\circ}$