Question

How do cis and trans isomers differ from one another?

Answer 1

Well for a start, they differ by their geometry.

Explanation:

But they should have different physical and chemical properties. The simplest case of cis-trans isomerism is provided by `"2-butylene"`, i.e. `H_3C-CH=CH-CH_3`

![https://useruploads.socratic.org/ibduZ8efRjS3aTePdv1Z_butene_1.png)

For each isomer, the connectivity is the same: `C1` connects to `C2`.........to `C4`. And yet their geometry is manifestly different, and this geometric difference will manifest in different physical and chemical properties. They differ in density, boiling point, and melting point, (unexpectedly the trans isomer is more volatile than the cis though the trans isomer has a higher melting point).