Question

Why does nothing happen to us when we drink water, as our stomach contains HCl and when water is added to conc. Acids, a highly exothermic reaction takes place?

Answer 1

As we know that hydrochloric acid is a chemical compound having the formula $HCl$. And it is also known as muriatic acid. This is an aqueous solution of hydrogen chloride or it is a water based acid. The hydrochloric acid is produced naturally in the human stomach and takes an important role for the digestion of food. And this is also used in other industries to prepare photoflash bulbs, batteries, and fireworks etc. And by using hydrochloric acid, we can make gelatin from sugar.

Complete answer:
We need to know that the hydrochloric acid are present in our stomach and it is helps fort the digestion. But it is not in a concentrated form. The hydrochloric acid is present in the stomach in quite dilute form. And the pH of that acid is less than $1.5$. If it is in extreme level, there is only $0.03$ molar hydrochloric acid. But that little amount of hydrochloric acid is also stabilizing by dissociation and it will converts in to solvated ions. Hence, when we drink water, there is no chance of any explosion due to the dilute concentration of the hydrochloric acid.

Note:
We have to remember that the hydrochloric acid present in our stomach is in much diluted form. And the acid will completely ionize in the water and there is a formation of hydronium ions and chlorine ions. Hence, no exothermic reaction takes place when we drink the water. The hydrochloric acid is present in the gastric juice and it helps to the formation of proteins breaking the digestive enzymes and food.