The human stomach secretes an acid that helps in the digestion of food. This is actually a concentrated hydrochloric acid formed by the combination of hydrogen and chlorine in your stomach. It helps in the early stages of digestion by enzyme activation and also aids in preventing infection.
Acids are measured on a scale known as the pH scale which goes from 0 to 14, with 0 being the most acidic, 7 being neutral and 14 being the most basic. The stomach acid has a pH of about 1.5 to 3.5.
A study to assess the in vitro effects of the stomach acid on metal objects have shown a partial to complete dissolution of razor blades.
The stomach is coated with a mucosal lining that protects it from being digested by such a strong acid it produces.