[aft_lizard]

Umm take intro to chemistry H₃O⁺ is what you get your pH from. I don't know how best to describe it to you but it is one of the first things I learned in chemistry.

[tracer]

Same here — covered over by too many courses in biochem and ensuing years. Thanks for the reminder....

[tracer]

"The mathematical definition of pH is a bit less intuitive, but with a calculator in hand, more useful. It says that the pH is equal to to the negative log of the hydrogen ion concentration, or pH = -log [H+]."

"Using the Brønsted-Lowry approach that would be pH = -log [H3O+]."

I must have been doing tissue culture (= using buffered media) for many years while "in the dark." Too many moons ago, but with good results. But my current level of memory seems to be declining in a logarithmic manner. Groan....