Which of the following is a CH₃-H eclipsed conformation for butane?

Question

Quizplus · Accepted Answer

The eclipsed conformation is when the methyl groups on the adjacent carbons are in the same plane, causing them to overlap and interact repulsively. Looking at each option:
I) The two methyl groups are in gauche positions (60 degrees apart), not eclipsed.
II) The two methyl groups are both on a horizontal plane, indicating an eclipsed conformation.
III) The two methyl groups are in anti positions (180 degrees apart), not eclipsed.
IV) The two methyl groups are both on a vertical plane, indicating an eclipsed conformation, but with a different angle than option II.

Which of the Following Is a CH3-H Eclipsed Conformation for Butane

Which of the Following Is a CH₃-H Eclipsed Conformation for Butane