In terms of pH, how does a lower substance pH relate to acidity?

A lower pH indicates a higher concentration of hydrogen ions (H⁺) in a solution, which correlates directly to increased acidity. The pH scale ranges from 0 to 14, with lower values representing more acidic conditions. For instance, substances with a pH below 7 are considered acidic, while those at pH 7 are neutral, and those above 7 are basic or alkaline.

Given this understanding, when a substance has a lower pH, it signifies that it has more hydrogen ions available, thus making it more acidic. This relationship is fundamental in chemistry and helps in categorizing different substances based on their acidic or basic properties.