What does the pH scale measure?

The pH scale is specifically designed to measure the acidity or alkalinity of a solution. It quantifies the concentration of hydrogen ions (H⁺) present in the solution, allowing us to determine whether a solution is acidic, neutral, or basic (alkaline). A lower pH value indicates a higher concentration of hydrogen ions, which corresponds to higher acidity. Conversely, a higher pH value indicates a lower concentration of hydrogen ions and thus a more basic solution.

The scale typically ranges from 0 to 14, with 7 being neutral, values below 7 indicating acidic solutions, and values above 7 indicating basic solutions. This measurement is fundamental in chemistry, biology, environmental science, and many other fields where the properties of solutions play a critical role. Understanding pH helps in various applications, such as agriculture, water quality testing, and chemical reactions.