Solution:

Acidity is also referred to as acid reflux. It is a common medical condition caused due to excessive production of acid by the stomach, which flows back into the food pipe and causes pain or burning sensation in the lower chest area.

The digestive fluid of the stomach also called the gastric juice or stomach acid is mainly composed of sodium chloride (NaCl), potassium chloride (KCl), and hydrochloric acid (HCl), Among these acids, the hydrochloric acid is the strong acid, which plays a vital role in the break down of food molecules and destroys the invading pathogens along with the food particles.