PLEASE SOMEONE HELP I BEG: when you have distilled water and add 1 drop of HCL (Acid) there is a large drop in pH, but when you add 2 more drops the change in pH isn't as drastic, why?!

Question

PLEASE SOMEONE HELP I BEG: when you have distilled water and add 1 drop of HCL (Acid) there is  a large drop in pH, but when you add 2 more drops the change in pH isn't as drastic, why?!

jamierox4ev3r · Answer

I would think that distilled water, since it has a pH of 7 when neutral, would go down drastically. The reason for this being that one drop of HCl probably contains many H+ ions, which drastically overcome the OH- ions that are in water to make the whole solution very acidic. Therefore, the first drop has the most noticeable change. As you keep adding more and more acid, the effects of OH- have already been negated so while you still see the pH decreasing, the drop will not be as dramatic as the first one.

Does that make sense? @lmplotch