[LukeJD]

I'm trying to determine how much pH up or pH down to include to change a liquid to a set pH.

For example, if I had 5L of liquid at a pH of 7 and I wanted to drop it to a pH of 5 with another liquid that has a pH of 2 how much of the pH 2 solution should I add to the pH 7 solution to get it to land on pH 5?

I know the pH = -log[Base10](aH) equation but I'm trying to figure out how to distill it into something I can use.

Thanks,

Luke

[Borek]

As long as you ignore fact that water autodissociates it is just a dilution problem.

http://www.chembuddy.com/?left=concentration&right=dilution-mixing

Calculate how much acid (H⁺) you will need in the solution, calculate volume of pH 2 solution that contains this amount of acid - and you are done.

As long as the final pH is not too close to 7 water autodissociation doesn't play any significant role, so it CAN be safely ignored.

[LukeJD]

That seems pretty straight forward.   Thanks