What is a solution that has a pH above 7.0 considered?

A solution with a pH above 7.0 is considered either basic or alkaline, as both terms refer to substances that exhibit properties opposite those of acids. In the pH scale, which ranges from 0 to 14, a value of 7.0 indicates a neutral solution, such as pure water. Values below 7.0 signify acidity, where the concentration of hydrogen ions exceeds that of hydroxide ions. Conversely, when the pH rises above 7.0, it indicates a higher concentration of hydroxide ions, making the solution basic or alkaline.

Essentially, basic and alkaline are interchangeable terms in the context of pH, both describing solutions where the concentration of hydroxide ions is greater than that of hydrogen ions. Understanding this distinction helps in various cosmetology applications, as many products rely on specific pH levels to function effectively on hair and skin.