In this video we'll use logs (logarithms) to calculate pH and pOH. Don't worry if you don't know your log rules: in this chapter, you won't stress your precalc beyond knowing how to find the log button on your calculator.
Converting pH & pOH to Molarity
In the previous video we saw how to calculate pH and pOH from concentration using a simple formula. In this video we'll do the opposite, turning pH and pOH into molarity. As usual we'll be doing it in style, using simple formulas rather than most teachers' preferred method, which usually involves rolling their eyes and expressing dismay that you don't remember your log rules from Algebra 2.
Converting Between pH & pOH
It turns out that for any given solution (of stuff dissolved in water anyways), the pH and pOH have to add up to 14, no matter what kind of crazy acid or base you put in. I know I know I know, this is the kind of stuff that keeps you up at night pondering the complexities of the universe.
Auto-Ionization: Why Is Water pH 7?
Pure water, strangely enough, always has some H+'s and OH-'s kicking around. Otherwise it wouldn't have a pH of 7. And a pOH of 7. But where did these H+'s and OH-'s come from, and where are they going? It's dynamic equilibrium, man.
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