I'm working on a lab for reaction rates of water/antacid and HCl/antacid.
I understand why water at various temperature react at different rates, but I don't understand why the neutralization reaction for HCl and and antacid takes almost as long as cold water.
Things I know:
In the acid-base reaction, HCl is a strong acid that fully dissociates. Bicarbonate is a weak acid and does not 100% accept H+.
Le Chatlerlier's principle states that when a stress is put on a system, equilibrium shifts to rebalance the system.
We aren't concerned with surface area, but it can have an effect. We were only watching the largest piece, however.
I can see that there would be much more free hydrogen ion in the acid-base solution. So maybe it just takes longer to fully neutralize compared to water, because the alka-seltzer bicarbonate Ion is only reacting with the hydrogen ion from citric acid and neutralizes more quickly.
Those aren't very satisfying answers. I just can't think of what about a neutralization reaction that would make it take longer. Is the activation energy significantly higher?
A point in the right direction would be welcome.