[sjbyrne]

Question:
If two aspirin tablets, each having a mass of 325mg, are dissolved in a full stomach whose volume is 1L and whose pH is 2, what percent of the aspirin is in the form of neutral molecules? (At body temperature, the Ka for aspirin = 3*10^-5)

My train of thought has led me to believe that my equation will be [H+]/(initial concentration of HCl) x 100, but the [H+] is not just concentration H+ given by HCl - I also have to take into account the aspirin to get the right [H+]. I am going to need to set something equal to the Ka of aspirin (presumably x^2/3.6*10^-3) which gives me x = [H+] = [C9H7O4-] = 3.29*10^-4.  Is this correct?

[sjbyrne]

Never mind - figured this one out on my own after trying a couple of different things.