Geometry

[Alan Chien 1J]

When I look at cyclopentane, I know it has an envelope conformation when it is puckered but I does it have a cis and trans like cyclohexane. If you fill in one hydrogen, the other carbons can't alternate axial up and down because there are only 5 carbons and that would not make sense. Does it have some kind of pattern when drawing the conformation?

[Chem_Mod]

Cyclopentane can have cis and trans. At each carbon of the cyclopentane, you can have substituents pointing either up or down. Cyclopentane is kind of in a "fixed" position, so it doesn't do chair flips like cyclohexane can, so something that's axial in cyclopentane remains axial, and something that's equatorial in cyclopentane remains equatorial.

Cis/Trans and axial/equatorial are two separate things.