When the relative energies of the s-cis and s-trans conformers of 1,3-butadiene are compared, one finds that ________.
A) the s-cis conformer is lower in energy than the s-trans
B) the s-trans conformer is lower in energy than the s-cis
C) the two conformers are of equal energy

Question

Quizplus · Accepted Answer

The s-trans conformer is lower in energy than the s-cis conformer due to steric hindrance. In the s-cis conformer, the hydrogens on each end of the molecule are too close together and experience repulsive interactions, while in the s-trans conformer, they are further apart and do not experience as much steric hindrance.

When the Relative Energies of the S-Cis and S-Trans Conformers