Bronsted-Lowry concept
Bronsted-Lowry in 1923 as a substance which gives up proton (proton-donor) and base as a substance which accepts proton (proton acceptor). Thus for example, in the following cases the species B accepts a proton and thus behaves as a base, while the species BH+ gives up a proton and thus acts as an acid.
\(\underset {\,\\\text{base}}B + \underset {\,\\\text{proton}}{H^+} \rightleftharpoons \underset {\,\\\text{acid}}{B^+H}\)
Such related pair of an acid and a base is said to be conjugate to one another, e.g., in the above example B is the conjugate base (cB) of the acid B+H, and B+H is the conjugate acid (cA) of the base B. On the whole, we can say they every base has its conjugate acid and every acid has its conjugate base. As a rule, a strong conjugate acid has a weak conjugate base and a weak acid has a strong conjugate base.
Thus according to Bronsted-Lowry concept, neutralization is a process in which a proton is transferred from an acid to a base. Remember that all Arrhenius acids are also Bronsted acids but all Arrhenius bases are not Bronsted bases.
