can someone explain how much app owners get when someone views our ads?

i'm trying to figure this out. i know other ad networks pay per click so if i pay $5 for an ad click the publisher gets like $2 or $3 per click.

but because facebook ads pays per CPM what does that work out as? is it still the same sort of 50 50 split where the ad network takes half and the publisher gets half, or is it different?

does anyone know?