What pH level indicates that water is neutral?

Water is considered neutral when its pH level is 7. This value is significant because it represents the point at which the concentration of hydrogen ions (H⁺) equals the concentration of hydroxide ions (OH⁻) in the solution. At this level, the water is neither acidic nor basic.

In the context of the pH scale, which ranges from 0 to 14, values below 7 indicate acidic conditions and values above 7 indicate basic (or alkaline) conditions. Therefore, a pH of 5 represents an acidic solution, while pH values of 9 and 10 indicate basic solutions. Understanding the pH scale is crucial for various applications, including refrigeration and air conditioning, where water quality can impact system performance and efficiency.