Question

What is a base according to bronsted- Lowry?
A.A proton acceptor
B.A proton donor
C.The substance that dissolves in water
D.A producer of hydroxide ions
E.A producer of hydrogen gas

Answer 1

Hint: First of all let’s recall the law or theory that Bronsted and Lowry introduced. These two scientists stated that acids and bases can be differentiated on the basis of their ability to release or accept the hydrogen ions \[{H^ + }\] .

Complete answer: So, According to Bronsted-Lowry concept, the chemical species that accepts the hydrogen ions \[{H^ + }\] is the bronsted-Lowry base and the species that gives or donates its hydrogen ion \[{H^ + }\] , is known as bronsted-Lowry acid.
Let’s have a look at the simple example to understand this Bronsted-Lowry concept:
\[HCl + N{H_3} \to C{l^ - } + N{H_4}^ + \]
As, we can see, here hydrochloric acid donates its \[{H^ + }\] ions, so it is a Bronsted-Lowry acid. On the other hand, ammonia accepts hydrogen ions from the hydrochloric acid, so it is a Bronsted-Lowry base.
So, from the above discussion, it is crystal clear that the chemical species that accepts hydrogen ions \[{H^ + }\] is the base.
So, the correct option is A.

Note:
Originally, there are three theories that define the identification of acid and base. All the theories are slightly different from each other. The theories are: the first – Arrhenius theory, the second Bronsted-Lowry theory and the third one Lewis acid – base theory. The Lewis acid base theory says that the acid is the chemical species that accepts the lone pair of electrons and the base donates lone pairs of electrons.