This is part of a marathon problem, we have to identify the five compunds of H, N, and O. As well as write a Lewis structure that is consistent with the info. PLease help I don not even understand the ?

a. All the compunds are electrolytes, although not all of them are strong electrolytes. Compunds C and D are ionic and compund B is covalent.

b. Nitrogen occurs in its highest possible oxidation state in compunds A and C; nitrogen occurs in its lowest oxidation state in compunds C,D, and E. The formal charge on both nitrogen in compund C is +1; the formal charge on the only nitrogen in compund B is 0.

There just isn't enough information to give DEFINITIVE answers to the identy of these five compounds. We could make some educated guesses and we might or might not come up with the right answers. From your post I assume there is more to the problem than what you have posted. If we had ALL of the problem I expect it would make things easier for us.