Amines Acidification - Ammonia

If you add 15 drops of 6M HCl (a source of H+) to a mixture of 10 drops of 6 M ammonia solution and 1 dropperful of demineralized water, what would the following be:

1) pH

2) solubility

3) observed chemical reactions that would occur

If you were to re-basify the solution by adding 20 drops of 6 M NaOH (which is a source of OH-), what would the following be:

1) pH

2) solubility

3) observed chemical reactions that would occur

Using structural formula, how would you write the chemical reaction which explains how the product of the acidification reaction reacts with OH-.

How would this explain the changes in solubility?