pH is a measure of the acidic or basic (alkaline) nature of a solution. The pH scale ranges from 0 (most acidic) to 14 (most basic).

• A neutral solution (pure water) has a pH of 7.
• Solutions with a pH less than 7 are acidic, with 0 being the most acidic.
• Solutions with a pH greater than 7 are basic (alkaline), with 14 being the most basic.