Bronsted-Lowry theory of acids and

The Bronsted-Lowry theory of acids and bases referred to in Section 10.7 can be applied equally well to reactions occurring during acid-base titrations in non-aqueous solvents. This is because their approach considers an acid as any substance which will tend to donate a proton, and a base as a substance which will accept a proton. Substances which give poor end points due to being weak acids or bases in aqueous solution will frequently give far more satisfactory end points when titrations are carried out in non-aqueous media. An additional advantage is that many substances which are insoluble in water are sufficiently soluble in organic solvents to permit their titration in these non-aqueous media. 

The term proton in these definitions refers to the hydrogen ion, H+. An acid is a species containing an acidic hydrogen atom, which is a hydrogen atom that can be transferred as its nucleus, a proton, to another species acting as a base. The same definitions were proposed independently by the English chemist Thomas Lowry, and the theory based on them is called the Bronsted-Lowry theory of acids and bases. 

The Bronsted-Lowry definition of an acid is essentially the same as Arrhenius idea An acid is any substance that releases a hydrogen ion. Their idea has come to be known as the Bronsted-Lowry theory of acids and bases. 

Unlike the Arrhenius theory, the Bronsted-Lowry theory of acids and bases can explain the basic properties of ammonia when it dissolves in water. See Figure 8.4. 

These ideas were rather limiting since they only applied to aqueous solutions. There were situations where acid-base reactions were taking place in solvents other than water, or even in no solvent at all. This problem was addressed in 1923 by the Danish chemist Johannes Bronsted (1879-1947) and the English chemist Thomas Lowry (1874-1936) when they independentiy proposed a more general definition of acids and bases, and the study of acids and bases took a great step forward. This theory became known as the Bronsted-Lowry theory of acids and bases. 

Arrhenius and Bronsted-Lowry theories of acids and bases... 

Bronsted-Lowry theory of acids and bases the theory defining an acid as a substance from which a hydrogen ion can be removed and a base as a substance that can remove a hydrogen ion from an acid (10.1)... 

Bronsted-Lowry Theory of Acids and Bases Conjugate Acids and Bases Add-Base Properties of Water... 

According to the Bronsted-Lowry theory of acids and bases, an acid is a proton donor and a base is a proton acceptor. The proton, which in this context means a hydrogen ion, H , is highly mobile and acids and bases in water are always in equihbrium with their deprotonated and protonated counterparts and hydro-nimn ions (H3O , 8). Thus, an acid HA, such as HCN, immediately estabhshes the equihbrium... 

In a reaction at equilibrium, products are being converted to reactants at the same rate as reactants are being converted to products. The reverse reaction can also be considered in terms of the Bronsted-Lowry theory of acids and bases. 

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