An acid is a solution with ph between (most acidic) and less acidic

Acid solutions have a pH between 0 (most acidic) and 7.0 (less acidic).

Explanation:

The pH (Hydrogen potential) of a solution indicates its molecular concentration of Hydrogen ions. The pH scale measures the acidity or basicity (alkalinity) of a solution. It goes from 0 to 14 and is balanced at 7.0 (neutral); everything below 7.0 is acidic, and everything above it is  basic/alkaline. The lower the pH, the higher concentration of hydrogen ions.

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