Helium (he) and neon (ne) are elements in group 8a of the periodic table. how do the electron dot diagrams of these elements compare?

They both have full outer electron shells, helium with 2 and Neon with 8, but obviously have different numbers of maximum numbers of electrons in their outer shells. Helium has 1 electron shell where Neon has 2, with 2 in the first and 8 in the second. Helium has 2 electrons in total where Neon has 10 in total. 

stands for electromotive force and it is measured in volts. despite its name, it is not actually the force in the sense of being a "pushing" or "pulling" (not measured in newtons).an equation that relates emf,  ℰ,  to a battery's terminal voltage, v, current, i, and internal resistance, r, is    ℰ = v + irin this case, the emf can be interpreted as a voltage—a difference in electric potential.i would not say that it would be considered an energy. if emf can be defined as the energy/work per a unit charge from a battery or other electric source, then it is not strictly energy.