Stomach acid is a very low pH, yes. But your stomach doesn’t always just have acid hanging around in it when it’s empty. (There are separate organs that create, store and secrete stomach acid into the stomach specifically when it’s needed and in response to certain hormonal processes, or other factors).

Right, but when we eat, we normally drink water. And that is when we normally have an influx of stomach acid.

Yes. And back to your original questions…

Yes water molecules get protonated to form H3O+. These molecules get filtered out into blood from capillaries in the small intestine as part of digestion.

Then, in the blood, the amount of H3O+ gets really tightly regulated (turning between H3O+, H2O and OH-) by a bunch of specific molecules that are called buffers (a sort of category of molecules) that regulate the pH of your blood.

If the pH of your blood falls too far out of this range, by having too many/few of these H3O+ molecules, or a breakdown of the above process/other molecules involved, having too few/too many buffers, etc. that can be very deadly, very quickly.

Woa thats cool, thanks for the explanation! If im understanding this correctly, the OH- and H3O+ molecules formed from water by the buffer basically serve to control the pH of your blood?

“Controlling the blood” is what buffers do (for blood pH).

Buffers don’t split water into H3O+ and OH-, that happens from stomach acid… buffers are in your blood… (and water has already been split into H3O+ and OH- before those molecules get to the buffers).

Ohhhh i gochu now, thanks!