What is the highest value on the pH scale?

The highest value on the pH scale is 14. The pH scale ranges from 0 to 14, where 0 represents highly acidic solutions, 7 is neutral, and 14 indicates highly alkaline (basic) solutions. A pH of 14 means that the concentration of hydrogen ions in the solution is extremely low, making it very basic. While some specific solutions may have pH values exceeding 14 under certain conditions, in standard aqueous chemistry and the typical use of the pH scale, 14 is recognized as the upper limit. This is relevant in water treatment and other environmental applications, where maintaining neutral to slightly alkaline values is often desirable for the health of aquatic ecosystems and the effectiveness of disinfection processes.