Arrhenius Base Definition

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An Arrhenius base is a substance that when added to water increases the number of OH- ions in the water. The base dissociates in water to form hydroxide (OH-) ions. It may decrease the aqueous hydronium ion (H3O+) concentration.
Arrhenius bases follow the reaction:
base + H2O → conjugate acid + OH-


  • Paik, Seoung-Hey (2015). "Understanding the Relationship Among Arrhenius, Brønsted–Lowry, and Lewis Theories." Journal of Chemical Education. 92 (9): 1484–1489. doi:10.1021/ed500891w