This is part of a marathon problem, we have to identify the five compunds of H, N, and O described below. For each compound, I have to write a Lewis structure that is consistent with the information given.

Question

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.

c.) Compund A and E exist in solution. Both solutions give off gases. Comercially available concentrated solutions of compund A are normally 16 M. The commercial, concentrated solution of compound E is 15 M.

d) Commercial solutions of compund E are labeled witha misnomer that implies that a binary, gaseous compund of nitrogen and hydrogen reacted with watert to produce ammonium ions and hydroxide ions. Actually this reaction occurs to only a slight extent.

e) Compound D is 43.7% N and 50.0% O by mass. If compound D were a gas at STP, it would have a density of 2.86 g/L.

f) A formula unit of compund C has one more oxygen than a formula unit of compound D. Compounds C and A have one ion in common when compound A is acting as the strong electrolyte.

g) Solutions of C are weakly acidic; solutions of compound A are strongly acidic; solutions of compound B and E are basic. The titration of .726 g of compound B requires 21.98 ml of 1.000 M HCl for complete neutralization.
I have no idea where to start for this problem. Please help me.

Answer 1

All of the "Railroad" problems have a give away line. This one has two and you need to know enough chemistry to recognize them when you see them.Let me give you the give away lines and a few hints and let you work on it.
A. The give away line is that commercially available stuff is 16M, it is a strong electrolyte, it has N in its highest oxidation state (+5) so this must be HNO3.
E. The give away lines are that commercially available stuff is 15 M AND (the most telling) is part d about gas forming NH4OH (the misnomer) so this must be NH3.

Extra hint: Look at part e. You can calculate a formula for that, both an empirical and a molecular formula.
Another hint: Look at part g. You can calculate a molar mass for compound B.