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Ok, so I got a question wrong in the TPR ICC and I don't really understand why. For those of you that have it, it is on page 69 question 5. You need these equations.
Equation: pKa (of drug) - pH = log(NI/I)
rate of absorbtion = NI/I
Which of the following would be most consistent with the results of the experiment mentioned in the passage?
A. Increasing the pH of the stomach results in increased absorbtion
B. The experimental drugs absorb at a slower rate than do their conjugate bases in the stomach.
C. A protein is isolated in the stomach membrane that is capable of transporting the experimental drugs
D. Increasing the temperature doesn't alter the results of the experiment
I know A and D are flat out wrong, but for some reason, I don't understand why B is wrong. I figured that the Ka any conjugate base of a compound will always be less than the Ka of it's protonated form, so therefore the pKa of the conjugate base will higher, thus giving a larger rate. Am I missing something here? I know this question is hard to answer without looking at the passage, but I think I gave enough info to solve it. I'll clarify if need be.
Edit: You know what, if you guys can't figure out the answer based on the super summarized version I gave you, is my logic correct for choice B? Is the pKa of a substance's conjugate base greater than the pKa of the original substance?
Equation: pKa (of drug) - pH = log(NI/I)
rate of absorbtion = NI/I
Which of the following would be most consistent with the results of the experiment mentioned in the passage?
A. Increasing the pH of the stomach results in increased absorbtion
B. The experimental drugs absorb at a slower rate than do their conjugate bases in the stomach.
C. A protein is isolated in the stomach membrane that is capable of transporting the experimental drugs
D. Increasing the temperature doesn't alter the results of the experiment
I know A and D are flat out wrong, but for some reason, I don't understand why B is wrong. I figured that the Ka any conjugate base of a compound will always be less than the Ka of it's protonated form, so therefore the pKa of the conjugate base will higher, thus giving a larger rate. Am I missing something here? I know this question is hard to answer without looking at the passage, but I think I gave enough info to solve it. I'll clarify if need be.
Edit: You know what, if you guys can't figure out the answer based on the super summarized version I gave you, is my logic correct for choice B? Is the pKa of a substance's conjugate base greater than the pKa of the original substance?
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