pH is a measure of how acidic or basic a substance is. It ranges from 0 to 14, with 7 being neutral. Substances with a pH less than 7 are acidic, and those with a pH greater than 7 are basic (or alkaline).
A solution with a pH less than 7; has more hydrogen ions than hydroxide ions.
Basic Solution (Alkaline): A solution with a pH greater than 7; has fewer hydrogen ions than hydroxide ions.
Neutral Solution: A solution where the concentration of H+ ions equals OH- ions; has equal amounts of both types of ions and a pH of 7.