do you know where I can find an actual diagram/drawing of a structure of an atom
I need to make one for helium
For a good picture showing both the electron cloud and a magnified nucleus for helium, see
http://upload.wikimedia.org/wikipedia/commons/thumb/2/23/Helium_atom_QM.svg/300px-Helium_atom_QM.svg.png
The nucleus appears as 4 colored particles (2 protons and 2 neutrons) stuck together in the center of the cloud. The colors are not real.