(Solved): 2. Buffers a. Parietal cells control the concentration of HCl in the stomach by secreting H+ and C ...

2. Buffers a. Parietal cells control the concentration of $$\mathrm{HCl}$$ in the stomach by secreting $$\mathrm{H}+$$ and $$\mathrm{Cl}?$$. While fasting, they maintain stomach $$\mathrm{pH}$$ at 3.0. After a meal, they decrease stomach $$\mathrm{pH}$$ to $$1.4$$. What is the fold-change in $$[\mathrm{H}+]$$ from fasting to after a meal? b. The $$\mathrm{pH}$$ of the stomach can influence the ionization of drugs such as Aspirin (aka acetylsalicylic acid or HAsp). Given that at equilibrium the $$\mathrm{pH}$$ of a $$0.1$$ $$\mathrm{M}$$ Aspirin is $$2.24$$, what is the $$\mathrm{pKa}$$ of Aspirin? c. Using the pKa from b., what is the ratio of Asp- to HAsp in the stomach of the patient after a meal?