Question

What is a Bronsted Base?

Answer 1

A Brønsted Base is a substance which can accept proton(s) or `H^+`.

An example would be `NH_3`

It has a high affinity to accept an `H^+` ion to form `NH_4^+`.
That's what makes it a Brønsted Base.

Consider `HCl` and `NH_3` in a region.
The acid `HCl` releases `H^+` and `Cl^-` ions. The Brønsted Base, `NH_3` accepts an `H^+` and results in formation of a salt, `NH_4^+Cl^-`.