Here's why:

* pH scale: The pH scale ranges from 0 to 14.

* Acidic: Solutions with a pH less than 7 are considered acidic.

* Basic (alkaline): Solutions with a pH greater than 7 are considered basic.

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

Think of it this way: The lower the pH number, the higher the concentration of hydrogen ions (H+) in the solution, which is what makes a solution acidic.