If you have not already done so, download Avogadro for free and watch the tutorials if necessary.
Build the structure of the cis-dichloroethene and trans-dichloroethene isomers with Avogadro and study their properties (sequenza Wiew → properties): in particular, check the energy values of the conformers and indicate which structure is more stable and why.
Do the same test with the cis-2-butene and trans-2-butene isomers: what do you notice? What do you think about that?
