Common table salt is a compound. A compound is a chemical substance in which two or more elements are joined together. An element is a substance that cannot be broken down into a simpler substance. Elements, either alone or joined together as compounds, make up every object. The elements sodium and chlorine join together to make table salt. Sodium is represented by the symbol "Na," and chlorine is represented by the symbol "Cl." Because one atom (smallest unit that has all the chemical and physical characteristics of an element) of sodium joins with one atom of chlorine, table salt is represented by the symbol "NaCl."

The Need for Salt

All animals, including humans, require salt. Salt is needed to regulate many bodily functions including maintaining a regular heart rhythm, blood pressure, and fluid balance in the body. Additionally, salt is required for nerve cells to communicate efficiently, and...