If I have 100ml of 99% IPA and want it PH to be 9 with 25% ammonia, how many millilitres of ammonia will need to be added to reach that?
Technically pH is a property of water solutions, while for sure there exist something like H
+ activity in the IPA/water solutions it is poorly defined and thus impossible to to calculate reliably.
I have 100ml of water with PH 7 and I would like to get it up to 11 witj 25% ammonia, how many millilitres I would need to add to reach that?
For this one you need to now how to calculate pH of the ammonia solution (hint: it is just a solution of a weak base). It gets a bit convoluted as you also need a way of converting % concentration to the molar one, not doable without knowing the density of the 25% solution.
If that 100ml of water with ammonia in it with PH 11 will be lowered to PH 9 with 10% vinegar, how much of vinegar will need to be added to reach that?
Starting point is the solution of the ammonia with the concentration calculated in the previous problem. You can try to approach the problem as if it was an ammonia buffer (assuming all ammonia reacts with the vinegar - this is not exactly true, as acetic acid is a weak, one, but should work reasonably good in this case).
I have tired to learn the way to calculate these, but I can't wrap my mind around these calculations and I am looking in to math at this point to learn those skills that I am missing at this point before I can use those equations needed to get answers.
Start with tutorials on concentrations and pH (perhaps Khan Academy), We can show you how to solve these problems, but if you don't know basics you won't learn much from that.