Here's why:

* pH scale: The pH scale measures the acidity or alkalinity of a solution. It ranges from 0 to 14.

* Acidic solutions: Solutions with a pH less than 7 are considered acidic. This means they have a higher concentration of hydrogen ions (H+).

* Basic solutions: Solutions with a pH greater than 7 are considered basic or alkaline. They have a lower concentration of hydrogen ions.

In summary: A low pH indicates a high concentration of hydrogen ions, making the solution more acidic.