Flight nurse, ground paramedic
You seem to have picked up some extra fluid somewhere. (H2O) + (CO2) <> (H2CO3) <> (HCO3-) + (H+) would be the result of your equation, and this is commonly used to demonstrate the carbonic-acid-bicarbonate equilibrium. Your equation needs an extra H2O on the left to make it correct and show the 2 equations, although to be honest I'm not sure that for the purposes of your average ambulance driver that it adds any useful info.
I've seen the equation written both ways, your way and mine. The way I wrote it [(H20)+(CO2) <-> (H2CO3)+(H2O) <-> (HCO3-)+(H3O+)] shows that there is extra fluid in the body, shows the role of water, and is not balanced. I see what you mean by saying that I would need an extra H2O on the left, but as this equation is not balanced (it just takes into account the excess fluid in the body), it's actually not necessary. Your way is probably a little bit clearer, because it takes water out of the equation. But the fact of the matter is, the water is still there in yours, you just don't see it in the equation. I hope this makes sense :wacko: