Why is the human body exposed to vinegar and things like that?

The acidity or sourness of vinegar brightens the flavor of food and adds balance to a rich dish. ... Vinegar can change the texture of foods. It breaks down the chemical structure of protein, such as when used as a marinade to tenderize meats and fish. Vinegar can also be used to make cottage cheese by adding it to milk. Is there any harm in trying vinegar, though? Vinegar mixed with water, juice, or another liquid is safe to drink, and it's fine to use it on food. However, with a pH between 2.4 and 3.3, vinegar is acidic enough to erode tooth enamel, inflame the esophagus and stomach, and trigger nausea and acid reflux.

Hope this helps Stay safe and have a Merry Christmas :D

a polar bond is formed when electrons are shared unevenly between atoms