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The Brønsted–Lowry theory is an acid–base reaction theory which was proposed independently by Johannes Nicolaus Brønsted and Thomas Martin Lowry in 1923. The fundamental concept of this theory is that when an acid and a base react with each other, the acid forms its conjugate base, and the base forms its conjugate acid by exchange of a proton (the hydrogen cation, or H+). This theory is a generalization of the Arrhenius theory. == Definitions of acids and bases == In the Arrhenius theory acids are defined as substances which dissociate in aqueous solution to give H+ (hydrogen ions). Bases are defined as substances which dissociate in aqueous solution to give OH− (hydroxide ions). In 1923 physical chemists Johannes Nicolaus Brønsted in Denmark and Thomas Martin Lowry in England independently proposed the theory that carries their names. In the Brønsted–Lowry theory acids and bases are defined by the way they react with each other, which allows for greater generality. The definition is expressed in terms of an equilibrium expression : acid + base conjugate base + conjugate acid. With an acid, HA, the equation can be written symbolically as: : HA + B A− + HB+ The equilibrium sign, , is used because the reaction can occur in both forward and backward directions. The acid, HA, can lose a proton to become its conjugate base, A−. The base, B, can accept a proton to become its conjugate acid, HB+. Most acid-base reactions are fast so that the components of the reaction are usually in dynamic equilibrium with each other. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Brønsted–Lowry acid–base theory」の詳細全文を読む スポンサード リンク
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