in my text book, it shows the carbon atom in a c=c double bond as having a dumb

[FreekGuy]

bell above and bellow as p? orbital. But this is confusing me, because I thought that only one electron per carbon atom went into forming a pi bond. Why is it drawn like this? what exactly is it? thanks

 

[steve_geo1]

You are confusing number of electrons with orbital probability distribution functions. The p-orbital is shaped like a dumbbell, but that's where the one electron is (most of the time). So the orbitals overlap top and bottom, but each dumbbell had only one electron in it. So now two electrons are both in two "hotdogs" over the top and bottom of the bond axis.