Help using an acid PKa 4.5 what is the movement through the GI tract from the stomach ph2 to stomach pH7.4 TY

Question

pH vs pKa in membrane transfer

Answer 1

It will go from associated to ionised. If the acidic group is carboxylate it will go from -COOH to -COO(-) + H(+). When the pH is at the pKa then there will be a 50% mix of both forms. It is usually considered that at 2 pH units below the pKa the acid group is fully associated (so this acid will be all -COOH up to pH2.5) and is fully ionised at 2 pH units above the pKa (so this acid will be fully ionised above pH 6.5).