The scale used to classify the strength of acid and basic solutions is called the pH scale.

Here's a breakdown:

* pH scale: Ranges from 0 to 14.

* Acids: Have a pH less than 7. The lower the pH, the stronger the acid.

* Neutral: A pH of 7 is considered neutral (like pure water).

* Bases: Have a pH greater than 7. The higher the pH, the stronger the base.

Important to remember:

* The pH scale is logarithmic, meaning that each whole number change in pH represents a tenfold change in acidity or basicity. For example, a solution with a pH of 3 is ten times more acidic than a solution with a pH of 4.

* The strength of an acid or base is determined by its ability to donate or accept protons (H+) in solution.