Give each group a shape name based on geometry. This one does not have to be "correct," but I want you to remember what the molecules look like for application later in the unit. H2O NH3 CH4 H2S CCl2F2 I've drawn both a Lewis dot drawing and a stereo projection for each but I still can't come up with any names. H2O and H2S could both be called triangles because, if you were to connect the two hydrogen atoms on a stereo projection, you'd have a triangle. CH4 and CCl2F2 could be squares...but what on Earth would NH3 be? If I were to connect it the same way, I'd get another triangle.