What Are Acids, Bases and Salts?
An acid is a chemical substance with a pH less than seven. An acid tends to dissolve certain metals, is corrosive, and tastes sour. A base, or alkali, is the opposite of an acid: it's a chemical substance with a pH greater than seven. For the record, seven is right in the middle, and is considered to be neutral. Bases are typically caustic, slippery, and taste bitter.
When an acid and base are mixed together, they neutralize each other and the final mixture has a pH in the middle of the scale. We can test whether something is an acid or base using indicator liquid or paper. Litmus paper is one type of indicator, and when put into a liquid acid or base, it turns blue for an acid, red for a liquid, and green for neutral.
When an acid and a base are reacted together, they form a salt. Table salt, or sodium chloride, is one example of this, but there are many, many salts in chemistry. Generally, when this reaction happens, the hydrogen that makes the acid an acid is replaced with a metal. So for table salt, hydrochloric acid (which is hydrogen and chlorine bonded together) loses its hydrogen, which is then replaced with the metal sodium, to make sodium chloride.
