Which two terms out of the 3, relate, and why?
4. atomic mass, compound, isotope
5. electron, ion, neutron
6. atomic number, isotope, radioactive
7. compound, ion, proton
8. energy level, neutron, spectral line

5. Electron and neutron- both are parts of the makeup of an atom
6. Atomic # and isotope- all isotopes of an element have the same # of protons, an elements atomic # is the # of protons that element has
(Those are all i know so if anyone else could chip in, that would be great!)

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf