pH   A symbol representing a measure of the effective concentration of hydrogen ions in a solution, pH = -log [H⁺]. pH is a measure of the acidity (or basicity) of a solution, where values of 0 to 14 are possible. Acid solutions have a pH < 7, basic solutions have pH > 7, neutral solutions have pH = 7.

Used in the following modules: Absorption, Distribution and Storage of Chemicals, Acids and Bases, Scientific Ethics, Scientists and the Scientific Community