Acid dissociation constant
|This article is a stub. Please help Sciencemadness Wiki by expanding it, adding pictures, and improving existing text.
An acid dissociation constant, Ka, (also known as acidity constant, or acid-ionization constant) is a quantitative measure of the strength of an acid in solution. It is the equilibrium constant for a chemical reaction known as dissociation in the context of acid–base reactions. The hydrogen ion does not exist as such in solution. It combines with a solvent molecule; when the solvent is water an hydronium ion is formed:
- H+ + H2O → H3O+.
This reaction is quantitative and hence can be ignored in the context of chemical equilibrium.