A salt is formed when an acid and a base react chemically. The process is called neutralization. When an acid and a base react, the hydrogen ions (H+) from the acid combine with the hydroxide ions (OH-) from the base to form water (H2O). The remaining ions from the acid and the base form the salt. For example, when hydrochloric acid (HCl) and sodium hydroxide (NaOH) react, the reaction is:

HCl + NaOH → NaCl + H2O

The products of the reaction are sodium chloride (NaCl) and water. Sodium chloride is a salt.