Which is more stable, cis or trans?

Question

Which is more stable out of these stereoisomers?

(a) cis-1,2-dimethylcyclopentane

(b) trans-1,2-dimethylcyclopentane

Answer 1

Cis means on the same side, while trans means across. In these two structures, you have a cyclopentane ring with two methyl groups. The cis structure will have the methyl groups branching from the ring on the same side, while the trans structure will have the methyl groups across from one another. The cis structure is less stable because of the steric hindrance that's created by the closely attached methyl groups. The trans structure in comparison is more balanced in design.

Answer 2

Not 100% certain; however, likely to be "trans." The reason why "trans-fats" were originally placed in foods was because they had a long shelf-life and were more stable than "poly- unsaturated fats."(CIS) However, now trans-fats are being removed due to there determinant affects on health. Anyway, that is how it pertains to nutrition and food science and likely that is the answer here as well.