Question

How do you classify Bronsted acids and bases?

Answer 1

Generally acids are considered as the compound releasing hydrogen ions to the atom whereas the base are considered as the compound releases hydroxide ions. According to Bronsted the definition of acids and bases were enhanced and was given according to proton donating and accepting species.

Complete step by step answer:
A chemist Johannes Nicolaus Bronsted and Thomas Martin Lowry in 1923 independently discovered a new definition of acids and bases based on the ability of the compound to either donate protons or accept protons. According to the Bronsted-Lowry acid-base concept, the acids are considered as the proton donor whereas the bases are considered as the proton acceptors.
Bronsted-Lowry theory of acid and bases was one step forward from the Arrhenius concept for the acid and base as not all the acid and bases substances are formed of hydrogen ion and hydroxide ion.
Let’s take an example of the reaction between the hydrochloric acid and ammonia.
The reaction is shown below.
$HCl(aq) + N{H_3}(aq) \to NH_4^ + (aq) + C{l^ - }(aq)$
In this reaction hydrochloric acid (HCl) donates the proton (${H^ + }$) to ammonia which accepts the proton to form a positively charged ammonium ion and the negatively charged chloride ion. Here hydrochloric acid HCl is a Bronsted-Lowry acid and ammonia is the Bronsted-Lowry base. The chlorine ion is the conjugate base of the hydrochloric acid and ammonium ion is the conjugate acid of the base ammonia.
A Bronsted-Lowry acid is a proton donor.
A Bronsted-Lowry base is a proton acceptor.

Note: You must be aware of one more term which according to Bronsted-Lowry theory is known as amphoteric. The amphoteric compounds are considered as those compounds which act as both as Bronsted-Lowry acid and base.