The most common definitions
of acids and bases are Arrhenius acids and bases, Brønsted-Lowry acids and
bases, and Lewis acids and bases.
Brønsted-Lowry acids and bases
- A Brønsted-Lowry base is a substance that accepts hydrogen ions during a chemical reaction. (Bases are proton acceptors)
- A Brønsted-Lowry acid is a substance that gives up hydrogen ions during a chemical reaction. (Acids are proton donors)
Arrhenius acids and bases
- An Arrhenius acid is a substance that when added to water increases the number of H+ ions in the water. Acid + H2O → H3O+ + conjugate base
- An Arrhenius base is a substance that when added to water increases the number of OH- ions in the water. Base + H2O → conjugate acid + OH-
Lewis acids and bases
- A Lewis acid is a substance that is an electron pair acceptor.
- A Lewis base is a substance that is an electron pair donator.