Many moderately large organic molecules containing basic nitrogen atoms are not very soluble in water as neutral molecules, but they are frequently much more soluble as their acid salts. Assuming that pH in the stomach is 2.5, indicate whether each of the following compounds would be present in the stomach as the neutral base or in the protonated form: nicotine, Kb = 7 ( 10-7; caffeine, Kb = 4 ( 10-14; strych-nine, Kb = 1 ( 10-6; quinine, Kb = 1.1 ( 10-6.