Questions on Acids and Bases

I'm just after doing a bit of study on this topic and have listed the areas that I am puzzled by. I don't expect anyone to answer them all. Every bit helps though!

1. Take a solution of ethanoic acid in water; Is the acidity level of such a solution based on the acidity of the molecule, or the quantity of the molecule? If the 5% solution is more acidic, then I would have to ask the following... if the forward and reverse reactions are taking place at the same rate, then doesn't this mean that there would be the same amount of conjugate base molecules in solution as there is acid molecules? So how is it considered an acidic solution if there's the same amount of base in it as there is acid?

2. In a video I recently watched about the pH of amino acids, I heard the following being said. "We can think of an acidic solution as having lots of excess protons". I can understand that a solution that has had an acid put into it, would have lots of excess protons. But if all the protons have been "donated", then how can it be considered an acid. This is something that's always confused me.

3. It's said that when acids and bases react in the right proportions, that neutralisation occurs. Is it poss for this to occur if one of the two (either the acid or the base) is neutral, and therefore only acting as a base/acid. Say with the case of ethanoic acid and water.

4. Does the neutralisation of an acid and a base always have to involve water? My chemistry book seems to suggest it does. If so, what about the reaction of [ammonia + HCl → ammonium chloride]? Is this considered a neutralisation reaction?

5. Regarding the above eqn to form ammonium chloride; it is said that this is an example of how Arrhenius's definition is limited as such a reaction would not be considered an acid base reaction. But since it is considered an acid base reaction, then this means that any two molecules (that both contain H) which combine to give one molecule, can be considered an acid and a base beforehand? Doesn't that mean that almost anything could be considered an acid or a base.

6. Is [HCl + NH3 → NH4Cl] one of the few examples of acid base reactions that has only one molecule on the right hand side? Is this more common for with acid/base reactions when water isn't involved?

7. Although there is no reverse reaction, what is the conj base of NaHCO3 in the eqn: [HCl + NaHCO3 → NaCl + H2O + CO2]?? Is it CO2 or H2O? Or is there none?

Thank you