Acid–base reaction models as theories that complement each other. For example the current Lewis model has the broadest definition of what an acid and base are, with the Bronsted-Lowry theory being a subset of what acids and bases are, and the Arrhenius theory being the most restrictive. The first scientific concept of acids and bases was provided by Lavoisier in around 1776. Since Lavoisier's knowledge of strong acids was mainly restricted to oxoacids, such as (nitric acid) and (sulfuric acid), which tend to contain central atoms in high oxidation states surrounded by oxygen, and since he was not aware of the true
Acid–base reaction the Brønsted-Lowry model, the solvent does not necessarily have to be water that is required by the Arrhenius Acid-Base model. For example, consider what happens when acetic acid, CHCOOH, dissolves in liquid ammonia. An H ion is removed from acetic acid, forming its conjugate base, the acetate ion, CHCOO. The addition of an H ion to an ammonia molecule of the solvent creates its conjugate acid, the ammonium ion, . The Brønsted–Lowry model calls hydrogen-containing substances (like HCl) acids. Thus, some substances, which many chemists considered to be acids, such as SO or BCl, are excluded from this classification due